Showing posts sorted by date for query kx3. Sort by relevance Show all posts
Showing posts sorted by date for query kx3. Sort by relevance Show all posts

Monday, April 24, 2023

Yaesu Interface Cable SCU-28

 TX Relay, Power and TX REQ IN

R&L Electronics sent me a SCU-28 10-pin DIN cable by accident and were nice enough to let me keep it.  Consider shopping from those guys.  They offer great communication and good prices.

This cable is typically used to wire connections for an external amplifier.  I don't have an external amplifier but I wanted to make use of the +12v power and transmit relay for the protection relay I built for my SDR-Play a few years ago.


I had also read that the TX REQ IN pin could be used to switch the radio into a lower power tune mode for use with external tuners. The absence of a TUNE button for external tuners is one of my pet-peeves about the FT-DX10 so I was excited to have one.

Wiring the Break Out Box and TX-REQ-IN

So I used my last spare plastic project box, some female phono jacks and found a push-button that I'd cut off of some other project in my junk box and went to work.


I used some shrink wrap for the momentary switch for the TX-REQ-IN pin.


I wired up 3 phono jacks... One for the TX relay, another for the +12v out, and one for the ALC control in case I ever do get an amp.  I safed the other wires for future use inside the project box.


Partial Success

I connected the box and verified that I was getting power for the relay and that the Relay Switch operated



Unfortunately, the TX-REQ-IN does NOT do what it does with other Yaesu transceivers.  Pressing the button grounds the TX-REQ-IN - the radio does transmit a carrier in any mode (here I tested with LSB) but rather than transmitted a reduced power carrier as it's supposed to, it just transmits at whatever wattage the mode is currently set to.  In this case I had the power set to 50w into a dummy load and it transmitted the full 50w rather than a reduced power 10w or 20w carrier for tuning.  See the power out on the radio's display


In my opinion Yaesu screwed the pooch on this one.  I don't see any reason why they wouldn't operate like they do with their bigger brethren radios when the TX-REQ-IN is grounded.  Some subsequent forum searching turned up posts from others that confirmed that the FT-DX10 does not properly respond to that signal.

My Elecraft KX3 and Ten-Tec Eagle both have a "TUNE" button that sends a low power tuning signal regardless of what the current power setting is at and there's no reason that the FT-DX10 shouldn't do the same.  Having to dive into a menu to change the power setting for tuning an external matching unit is just silly in this day and age.

I have confirmed that my box is working the relay properly to my SDR-Play.  I reference the relay I built to protect the front-end of the SDR-Play in this post https://www.hamradioqrp.com/2017/02/spruce-up-basic-transceiver-with-sdr.html

That's all for now.



So lower your power and raise your expectations




Sunday, April 16, 2023

Portable Ops in Comfort

Towable Shack

Working my rolling shack portable station from air-con comfort


We've had a few RV's over the years, but for some reason I've never thought to operate from inside the RV.  I have always tossed a wire over a tree and operated from a picnic table or from my camp chair, as here...




But I thought, "Hey, I have a 12v power supply built-into the RV and the built-in ladder makes a nice solid mount for an antenna mast."

Early try with a military fiberglass pole mast

Now I use a Flagpole Buddy with a 30 foot telescoping mast


Here's a link to the flagpole buddy... link

Our RV has a Converter / Inverter with a spare 25 amp 12v circuit.  I tapped into that and ran a power pole wire to the dinette table.  

The camper had a coax outlet to watch a TV outside the camper... that's obnoxious.  So I cut the cable TV coax and crimped on a UHF connector, and ran that to the dinette table.  I simply attach my coax from outside the camper to cable TV coax adapter to get the antenna connection inside the camper.  Wallah, coax through the wall with no drilling. The cable TV coax run from the dinette to the wall outlet is only a couple feet so it's not really impacting the impedance of the coax run to the antenna.

I've tried a couple of antenna's and have settled on my end-fed 44 foot wire fed with a 9:1 balun and some clip on radials.   I pull the antenna wire through top end of the telescoping mast with kite string, counter-weighted with a heavy sinker.  That keeps the wire taught from the end-fed point up to the top of the mast and out at an angle.

Gone RF fishing with a 30 foot pole and a big sinker.


The Elecraft KX3 and Ten-Tec Eagle will both match a bent spoon with their auto-tuners and have no trouble with the end-fed on 40m and above. 

For a portable key I use my Palm Radio Single paddle.  Either magnetically attached to the steel side of the Eagle or just held with one hand while operating with the KX3.

Palm Radio Single Paddle

On the Eagle the Palm Radio Single magnetically attaches to the side

One thing I find interesting about operating while "camping" (if you call towing a small house to a campground camping) is that I seem to also work a suprising number of other stations that are operating from a campground.

Note the power and antenna connections under the table


The KX3 can stay on the dinette and doesn't take much room.  Keeping the footprint small and the earbuds in, keeps the XYL happy when operating during an outing.

I worked a number of stations on 40m, 30m, 20m and 10m this weekend.  It's always fun to tell a station that you are portable, even if you are essentially operating in your home away from home.


Thats all for now.

Lower your power and raise your expectations

Rich AA4OO HamRadioQRP.com

Sunday, March 26, 2023

Yaesu FT-DX10

Shiny new Rig -- Yaesu FT-DX10

I ordered my FT-DX10 from R&L Electronics this week, along with a 300Hz Yaesu Crystal filter from Ham Radio Outlet, because R&L didn't have the crystal filter in stock.  This is my first order from R&L and I'm happy with their communication and slightly lower prices than the major equipment providers.  They also included an R&L Electronics branded 30A 12v supply for only $40, and I always seem to need a separate power supply.

FT-DX10 next to the KX3


Initial Impressions

It has been over 12 years since I used a Japanese brand transceiver.  Compared to the Elecraft KX3 and Ten-Tec Eagle the FT-DX10 has a higher level of fit and finish.  The case, buttons and switches have a high grade feel.  

I had previously not been able to physically see one of these radios and if I had I may have passed due to the way you physically interact with the radio. The button placement is decidely cramped.  Even though the KX3 and Eagle have significantly smaller front pannels, they both have good spacing between their buttons and knobs compared to the FT-DX10.  All the front panel space used by the FT-DX10's large display definitely reduces the space for physical controls.  

I probably touch the AF/RF knob more than any part of the radio.  It is small.  It is slightly smaller even than the AF/RF knob on the compact KX3, and much smaller than the control knobs on the Eagle.  It's proximity to the VFO has resulted in me accidently moving the VFO off-frequency multiple times.  I would have preferred Yaesu have a smaller VFO knob to make more room for the physical control surface.

Related to the "cramped" controls, I find myself regularly locking the VFO on this radio.  I've never needed to do that on another radio and it's a bit frustrating.  I'm assuming I will become more familiar with the placement and reduce my incidental presses with practice.

In Use

Audio

The audio from the built-in speaker sounds okay on SSB but is very muddy on CW.  I tried playing with some of the EQ controls but I think the large cabinet space under the speaker is just creating a bit of a CW echo chamber at the 450Hz frequency that I like to listen to code at.  CW output at a higher frequency doesn't have the muddy problem but I've developed a painful sensitivity listening CW at higher frequency.  I'm now using an old Vertex mobile speaker on top of the radio and that has cleaned up the CW audio.

Similarly, when using headphones I hear a lot of high frequency hiss even when the audio is turned completely down.  It requires an in-line resistance (outboard volume) or use of higher impedance headphones to eliminate the hiss.  I know a lot of older hams have lost much of their higher frequency hearing but I'm not there yet.

The "sound" of CW from the radio when gain levels are properly managed and the digital noise reduction is employed is quite nice.  It is MUCH better than the audio of the Elecraft KX3 but still not quite as good as the audio from the Ten-Tec Eagle.  The only thing I can say about it is that it sounds less musical than the Eagle.  At some point I will hook up an audio scope to both and compare the audio waveforms.  For now I don't mind listening to it but I haven't had the chance to spend hours listening.

Button mashing

I was concerned about how many times I would have to enter the menu during operation and so far I'm fairly pleased.  There are physical buttons for most of the functions I want to perform during a QSO.   I had considered buying the less expensive FT-710 rather than the DX10; but the MPVD (Multi-Purpose-VFO-Outer-Dial) on the DX10 provide a lot of value by having an additional control ring.  By having both a function knob tied to one of a dozen different functions, as well as being able to assign a function to the MPVD I find that I don't often have to go into the menu.  

Compared to my Ten-Tec Eagle it is easier to operate because the dual-use buttons on the Eagle are perpetually in the wrong mode for me.  Compared to the Elecraft KX3 it is about on-par usability wise.

I wish it had a dedicated knob for power but I understand that I am likely in the minority of people who start nearly every QSO at QRP levels then raise power if needed. Speaking of QRP, 5 watts is as low as the RF power can be set.  The Eagle will go down to one watt and the KX3 will go down to 1/10 watt.  

I am still a little confused about the APF (Audio Peaking Filter) functionality.  The button goes through 2 presses in CW mode and the second press seems to do something different but I'm unsure what that is.  The manual doesn't mention a second press.

The APF is not as effective as the APF on the KX3 at pulling out a weak signal, but the KX3's APF is very strong and makes the signal sound weird.  I don't normally leave it on.  The FT-DX10 APF doesn't negatively impact the sound of the signal but doesn't pull it out as much either.  Mabye there's something else in the menus I haven't seen yet.  

Features

FT-DX10 DNR (Digital Noise Reduction / as opposed to 'Do Not Resuscitate') works very well on CW.  It works much better than the NR (Noise Reduction) on the Eagle or KX3 for CW.  You have to play with the different DNR levels on any particular QSO to find the right match, but once you do it works very well.  I don't think it works as well on SSB as the NR on the Eagle, but blows away the NR on the KX3 on SSB.

The display, ah yes the display.  The display is large and colorful.  I tried using the 3DS (Three Dimension Waterfal) for about 30 minutes and while it is mesmerizing I don't find it as useful as the standard veritical waterfall.  In particular, when there are static crashes the historical 3D waterfall image creates a tall "wall" that makes it very hard to see the signals before and after the static crash.  Since we've had a lot of thunderstorms in the surrounding states (on Thursday evening one storm was producing 443 strikes a minute) it makes that 3D waterful useless.  

The standard waterfall is quite useful although precisely selecting the signal with you finger is very hard, so the mouse needs to be used.  

The internal tuner is matching all the bands on my 80m Windom including 30m which, according to my Elecraft W1 meter is 5:1.  It shouldn't be able to perform a match on that since it's advertised as a 3:1 tuner yet it's working.  YMMV.

The CLAR RX/TX (Clarifier) is what everyone else calls a RIT and it works very well.  When pressed the MPVD ring makes adjustment quick and easy and it both lights up the button as well as has an indication in the display so you don't forget it is engaged.

The ZIN (Zero In) is essentially the same feature as the SPOT function on the KX3 and it works very well to automatically zero beat a CW station.  I think it actually works better than the KX3's SPOT.

I haven't had need to work Split operation with it yet, but it has a button labled TXW which is a momentary button allowing you to listen to the transmit frequency which I think is nicer than having to swap the VFO's back and forth like I do on the Eagle.  However, it's not quite as spiffy as the KX3 allowing you to hear VFO A in one ear of your headphones and VFO B in the other.

As far as standard memories, its operation is a bit disappointing.  My Eagle and KX3 store both VFOA and VFOB frequencies when I save a memory, but the DX10 is only saving the VFOA frequency.  On the other radios I like to quickly jump up to SSB by simply pressing the VFO A/B swap but here I have to store that as a different memory.  That seems like an oversight, so I'm probably doing something wrong.

Nits

My biggest dislikes so far are related to how noisy it is in CW operation.  The T/R (transmit/receive) relay is very noisy.  Not in the same clacky league as the Heathkit HW-101 but still very noisy.  In full QSK it sounds like an old school typewriter in the radio.  My KX3 has silent PIN-Diode switching and the Eagle has a very quiet relay, nearly silent, so to hear the clacking doesn't put me in a happy place.  I've sinced changed my normal full break-in use to semi-break in and lengthened the timeout to 500ms.  I really, don't like that.  I do very conversational CW and like to hear the other station wanting to break-in or hear if I've accidentally infringed on someone.  I feel like I'm keying a repeater.

The other noisy thing is the fan.  The fan comes on even when not transmitting and it's quite noisy.  Compared to the Eagle which has internally baffled fans that you never hear and the KX3 has no fans at all; it creates a much noisier environment.  I wish they'd placed the fan inside the chasis like the Eagle so that it wasn't so loud.  I understand that again I'm in the minority.  Most operators are used to nosiy relays and noisy fans or have an amplifier running that sounds like a Window Air Conditioner, but I'm used to a very quite operating environment.

Headphone use would mitigate both the noisy relay and fan noise but many times I'm just doing casual operating and listening through the external speaker.

It has an "external display" connector to go to an external monitor but the resolution is 800x640.  That's like early 1990s monitor resolution.  Anything bigger than a 15" external monitor results in a great deal of pixelization on the display.  They could have upscaled the display to eliminate the pixelization which would make the external display looks less cheesy.

CW Decode works, sorta.  The radio was advertised as supporting CW decode.  The decoder covers up the waterfall and you have to exit decode to see the waterfall.  I do use CW decode on the KX3 if I'm trying to get a DX station that is sending his call at over 30wpm, and the KX3 displays about 12 characters of information while leaving everything except the VFOB frequency visible.  It's very useful on the KX3 and quite accurate.  The decoder on the FT-DX10 shows paragraphs of decoded CW.  I just want it for a quick assist, not to read 30 minutes of ragchew content from two ops.  The other issue with the DX10 CW decode is that you have to set the CW speed in the menu to match the speed or the accuracy is really poor.  Most decoders just figure it out.  Even the ardruino decoder I built works better. I just wish it displayed a single line in the bottom of the screen.

While we're on CW, it has a CW "memory keyer" function but you have to display the menu and touch the screen to send a CW memory during the QSO.  The memory keyer menu covers up most of the waterfall and going into any other menu function makes the "contest keyer" disappear.  There is a FH-2 keypad that I believe operates without having the menu displayed.  It's a very pricey $100 for a box with buttons connected to different resistance values, so I'll probably build one.  For now I'm using my external memory keyer, which also allowed me to have my manual keys in series with the external keyer output so I can use both mechanical keys and my paddle at the same time.

My KX3 has two key inputs and so does the Eagle, so while I knew the DX10 didn't have two key inputs it is still something I'd miss if I didn't use an external keyer.

Lastly, this is a NIT for me but I can't find anything on the interwebs that says other people have this issue.  I cannot get the radio to reliably interface with OmniRig.  I use OmniRig to interface my radio with Log4OM and other software.  I have searched and searched and others are not having this issue.  I am using the most recent FTDX10.ini configuration file for OmniRig and have it configured with the same serial port settings that work with N1MM (38400, N, 8, 2, Handshake, Low).  It is perplexing.  OmniRig continuously loses connection to the radio.  So this is likely some local PC / software problem I have that I shouldn't blame the radio for.  I even performed a full reset to no avail.

Conclusion

This is the first new HF radio I've ever purchased.  I've been licensed to use HF bands for about 16 years at this point, but I've only owned 6 other HF rigs in that time; all purchased used.  I've owned a number of Yaesu VHF mobile and handheld radios but only one HF and that was the FT-857D.  The FT-857 was a good, portable HF/VHF/UHF radio but due to the limited front panel space and very early DSP implementation was really on the struggle bus when used for HF.

For me this was a very expensive purchase.  So expectations are high.  I knew it was missing some features my other radios already had but I'd hoped the shiny display would make up for it.  At this point it's a mixed bag.  I do like the DNR very much and I can get clean sounding audio out of it using a external speaker, but that's about the only positive.  The clacky T/R relay and noisy fan are a major Debbie Downer at this point.

I know that since I'm primarily a CW operator most of the issues are unique to CW.  If I used Digital modes or did a lot of SSB I'd probably be thrilled with this radio.  If I can figure out the rig interface problems I may try some digitial modes again and maybe it would seem more shiny.   (I know I use the word "Shiny", a lot... It's because there was a Sci-Fi Series on a decade ago called Firefly. The chief engineer used that word for anything she thought was cool or nice... I have sort of adopted it)

I'll give it some more time and see how it works with weak signals.  So far, I've only made a few dozen contacts and less than a dozen extended ragchews due to lots of lightning in my area.  It's really a toss-up at this point as to whether the shiny stuff outweighs the musical audio, and slent operation of my Eagle.



That's all for now.

Lower your power and raise your expectations
73s Richard AA4OO

Monday, March 20, 2023

GAS is Rearing its Ugly Head

 GAS - Gear Aquisition Syndrome

I have some excellent radios.  I have a KX3 that does everything including ironing my pants (well almost) and a Ten-Tec Eagle that has the smoothest CW anyone could ever want.  I also have old crumugeonly radios that require the patience of Job to operate.  I've been well pleased with my collection of RF generating and receiving gear for quite a while.  However, my Eagle is showing its age.  I had to recently replace its T/R relay and the encoders need some cleaning, but it still sounds beautiful.

The problem is these newfangled rigs with their dang, pretty front panels providing information overload with aluring displays of 3D waterfalls and teleporter controls (maybe I mis-read that last one in the specs).  Many of my QSOs now are with operators that have shiny new rigs.  It's just not fair that I'm staring at a segmented LCD display... or in the case of my GRC/9, the front panel equivalent of a Slide Ruler.

The GRC/9 has the operating interface of a Slide Ruler
but wow it's fun to operate... slowly and noisily

The KX3 interfaces wonderfully to my Computer
but it looks dated

Surely ham life must be better when I can gaze at the equivalent of a smart phone on the front panel when using the oldest operating mode known to man?

The Genesis of "Want More"...

In preparation for the upcoming camping season in our RV, I wired a spare 12v 25A circuit in the camper's inverter to bring 12v rig power to the dining table, and co-opted the 75ohm cable running to the cable TV output outside the camper for watching TV (why would anyone watch TV outside the camper).  That cable TV output now takes my antenna connection out of the camper without drilling any holes.  I bought a stellar thing called a "flagpole buddy" to hold my 30 foot telescoping mast on the ladder and wallah, I have a portable Ham shack.  I was using my Ten-Tec Eagle on the dining table, and my wife was not-enthused with having half of the dining table consumed by my bleeping radio. I assured her I'd set it on the seat when not in operation, but I still received "the look".

The magnetic in the Palm Radio Paddle attaches to the side of the Eagle
when operating portable

Flagpole buddy holds the mast extending up to 35 feet

My KX3 would take up less space than the Eagle but it's a pricey little thing to leave in the camper, and I primarily use it now as my primary station in my home shack because it's wired up to the computer using HDSDR to provide a panadapter display. 

I had convinced myself that the KX3 should stay in the Shack. So being the wise and kind husband that I am; I started looking for a small, portable, inexpensive QRO capable radio, given the compromised antenna. All this was to please my wife of course.  

I used to own a Yaesu FT-857 that I kept in my truck, but it was terrible at CW (IMO) and that rig seems to be pretty rare now... After considerable searching I settled on a Yaesu FT-891.  They had good reports and I could separate the face and it would take up very little room on the table.  Plus it had a band-scope of sorts (ah shiny).  But alas, I couldn't find used ones that didn't look like they'd lived under the seat of an off-road vehicle racing in the Baja, and the new ones are out of stock everywhere.  All that web searching kept popping up the rigs with the pretty front panels.  Google decided it needed to serve me advertisements of pretty radios everytime I opened any web site.

GAS

So, I convinced myself that I needed to replace the KX3 in the shack with a shiny, teleporter control rig and permanently install the KX3 in the camper.  I could mount the KXPA100 QRP amp out of the way in the camper and leave the radio in my corner of the table.  I'd also easily be able to take it outside to the picnic table and run off battery.  My mind was made up, I needed the KX3 in the camper and a new shiny toy for the shack.

Reality Strikes

Here's the problem... my KX3 with its 10:1 auto-tuner, silent QSK relay, dual antenna ports (thanks to the KXPA100), built-in IF/IQ output, and dual key inputs (one for paddle and one for manual keys) just can't be found in a shiny, smart-phone panel radio without breaking my bank account.  So I'd have to settle for a "new rig" with fewer features than I've grown accustomed to.  Surely that would disuade me from this folly... but Google keeps serving me advertisements.

I will be soon be writing about my KX3 in the camper and my new, shiny, less-featured shack rig.

Blast you GAS ! 


Thursday, February 6, 2020

Space in Morse Code

Silence is Beautiful

The space between characters and words is just as important as properly forming the characters.




If you're rushing your characters the elements of one character will not be easily discerned from the next and the person your sending to will find it indecipherable and respond with a 73 and spin the dial.  I have a number of comments in my logs about operators who ran their characters and words together.  I tend to avoid those contacts down the log.

But, many of us, including myself, are guilty of rushing when we send, especially as a ragchew moves into the 3rd or 4th exchange.  I think the problem is that as the person sending the code, I know what I am sending and in the excitement of wanting to get out all the things I want to say and turn it over, I start to rush and begin compressing the space between my sent characters and words.  After all, it's very clear in my head what I'm sending, it must be just as clear to the listener, right?  Wrong.

RRFBCPYALLWXHRISSUNNYES88FRIGISIC756PRORUNNING100WINTODIPOLEUP66FTDESM8ERW8BJOK

The exchange above isn't far from reality and that's assuming the character spacing was good.  When the character spacing is rushed two characters become a different character or no character at all, and you sit there with your head tilted thinking "what in the world are they saying?"

Proper Space (Timing)

What is considered proper spacing?  Let's review some basics.  A DIT is counted as a single Morse Code element (think of it as a unit of time).  A DAH is counted as 3 times longer or 3 Morse Code elements (3 times the DIT time unit).  

Of course the length (time) of a sent DIT or DAH will change with the speed you are sending.  As the word per minute speed rises, the length of of DITs and DAHs decreases accordingly and vice-versa.  Unless you're using Farnsworth timing, but that's a different discussion...

Space between DITS and DAHS in a Character

Characters other than the E and T are made up of more than a single DIT or DAH.  Between each DIT and DAH making up a single character is space.  The space between each DIT and DAH making up a single character should be as long as a single Morse Code element... a DIT.  So there's a DIT's space of silence between every DIT and DAH in a character. 

"R" = DIT.DAH.DIT (where the '.' is the length of a DIT)

Space between characters within a Word

There should be 3 Morse Code elements of silence between each letter in a word, or silence the length of a DAH, at the speed you are sending.

"WORD" = W-O-R-D (where the '-' is the length of a DAH)

Space between Words

There should be 7 Morse Code elements of silence between each word you send.

"HERE<>ARE<>SOME<>WORDS" (where the '<>' is the length of a the M character)

The length of an "M" ??  Yes.  I was corrected about this in a video I made.  In that video I was counting the DITS and DAHS only, and said to count the inter-word space to be the length of the 'W' character because it is made of a DIT and two DAHS, but I was forgetting the space between the DITS and DAHS that make up the character.  A 'W' character contains 9 elements.  An 'M' contains 7 elements since it is 2 DAHS (3*2=6) plus the inter-character element that spaces them (1-element of silence) equals 7 Morse code elements.

How to Practice

If you use an electronic keyer it will take care of the inter-character spacing between the DITS and DAHS of your sent characters.  If you use a manual key you'll have to take care of that yourself.  You can practice by sending strings of DITS, listening to see if you are placing the same space between each DIT as the length of the DIT itself.  

To practice spacing letters in a word, get used to the length of a DAH (a 'T' character).  Send a T over and over making sure you have the space of the character and the space of silence equivalent.  This gets a bit more complicated with different characters.  An 'E' character is of course much shorter than a 'Z' character but you need to have the same amount of space after each before sending the next character.  I find that I tend to rush into the next character after sending a long character like an 'F 'or an 'L' and add too much space after short characters like an 'E' or 'T'.   If you use a decoder of some type it can be helpful in showing you timing mistakes.  Send into a decoder and see if it turns two of your characters into a different character (you rushed the timing), or see if it spaces the word out as if there's a word break (you're putting too much space between the letters).  It is a very humbling experience to send into a decoder.

Similar to working on letter spacing, spacing for words is potentially an even more important skill.  When we listen to Morse at speed the rhythmic sound of the characters in a word as a whole tends to tell our brain what we've heard.  If the next word is rushed then we don't process the first and miss the beginning of the next.  Practice sending the 'M' character at your preferred speed and get used to the amount of time it takes to send.  

One thing I've tried that works pretty well is setting the break-in timing of my transceiver to match the space I want between words.  At 20wpm the DIT length is between 50-60 milliseconds depending on the measurement you use.  So if I want to be sure I'm spacing properly I should have 7 time-units or 7*50 = 350 milliseconds break-in set in the transceiver.  Both my Elecraft KX3 and Ten-Tec Eagle support setting the break-in in milliseconds.  By being sure that I hear break-in occur between every word I know that I'm putting in a good minimum amount of spacing.  If I don't hear break-in occurring, it reminds me that I'm rushing my words.

When I hear break-in occur between every word I know that I'm putting in a good minimum amount of spacing

Conclusion

The silence you send is just as important as the signal.  Silence is golden



DE AA4OO


Sunday, January 7, 2018

Troublesome characters to copy in Morse Code

The trouble with DITS

KX3 Displaying some sent code and a Palm Single paddle in front, magnetically attached to a steel base

As I've learned the code one problem area, early on, was dealing with words that started with characters that were all DITS.  I'm probably not alone in having my puny brain overloaded when I am trying to head copy words that start with DITS.  I would panic because the all-dits character would fly by and I'd get fixated on trying to figure out what that was and miss the rest of the word.

To overcome DIT panic, I started training on the all DIT characters of E, I, S and H

Using https://lcwo.net/  I'd configure it to send only those characters, and practice them alone.  Then I started creating words that began with DIT characters and I'd practice recognizing them.

After two and half years I still get tripped up on occasion but I'm doing much better.  

I also like to practice sending DITS.  The following sentence is fun to practice: "SHE IS 55 ES IS HIS SISTER"




So how do you deal with DIT overload?  


That's all for now.
So lower your power and raise your expectations...

72/73
de Richard AA4OO

Tuesday, November 14, 2017

Thank you for my signal report

3 numbers can mean a lot


QRP operators strive to make the most out of a little.  So when we receive a signal report it means a lot to us.  But the common signal report, given using the R-S-T System, seems often to be misunderstood by some amateur radio operators.

RST has 3 elements:
  • R stands for Readability.  How easy or difficult is it to copy the characters or words being sent on a scale from 1 to 5, with 1 meaning unreadable ranging up to 5 meaning perfectly copy-able.
  • S stands for Signal Strength.  How strong is the signal on a scale from 1 to 9, with 1 being barely perceptible up to 9, being extremely strong.
  • T stands for Tone.  This is only used to describe a CW signal's tone.  Given modern transceivers there are few cases where you'd send anything other than a 9 meaning perfect tone, devoid of ripple or modulation. You'll rarely hear a report with a Tone report other than 9, but if you hear ripple or modulation artifacts you may send lower numbers but it will likely just confuse the other operator.  If you hear chirp (a rising or falling tone) you may wish to append a 'C' to the RST to indicate that.
I want to concentrate on Readability and Signal strength.

Readability

I believe most of us are guilty of focusing on the signal strength portion of the report rather than readability.  But readability can convey a lot to the operator receiving the report.  

For instance if you have a lot of local noise or if the band is noisy due to magnetic disturbance or there's QRM or QRN readability may be difficult.  Similarly, if the operator is using poor technique and running letters or words together that affects readability.

It's possible that signal strength may be good or even moderately strong (6 or 7) but for some reason copy is difficult.  It would be worthwhile to send a 2 (Barely readable, occasional words distinguishable) or a 3 (Readable with considerable difficulty) for the 'R' portion of the signal report as in 359.  Then follow up with WITH QRM or WITH POOR SPACING, to make the other operator aware that you're having trouble copying.

I will occasionally have an operator send me a 3 for R but it seems to always be related to low signal strength.  If someone sends you a 3 or a 4 and it's not followed by an equally low signal strength number inquire as to the difficulty in readability.  It may be something you can correct on your end.

Signal

Signal seems obvious but it's not.  

I believe that many operators use the reading on their S-meter to report the Signal strength but different manufacturers calibrate their S-meters quite differently. The difference between S-units is supposed to be 6 dB but that's often not the case.  On many rigs the use of the preamp or the attenuator also effects the displayed S-meter reading.  So the S-meter is not an accurate reflection of what Signal strength is supposed to convey.  

My old Ten-Tec Century/21 doesn't even have an S-meter.  Neither do my homebuilt QRP radios.

So, what should we be using?  Well how about the actual meaning of the system:
  1. Faint—signals barely perceptible
  2. Very weak signals
  3. Weak signals
  4. Fair signals
  5. Fairly good signals
  6. Good signals
  7. Moderately strong signals
  8. Strong signals
  9. Extremely strong signals
Obviously this is a subjective report, but on my KX3 my S-meter may read 2 when the signal actually sounds Good (6), so I send a 6 even though the meter reads 2.  If I were to send the other station the S-meter reading of 2 they'd assume I'm barely copying them, because I sent them a 529.

I think you can start to see the point.  Use the system as it was designed, before radios had S-meters and the Signal report will have more meaning to the station receiving the report.

My Ten-Tec C21 doesn't have an S-meter but it does have AF and RF gain controls.  I will commonly run my AF gain at a high level and use the RF gain to control the volume of the received signal.  This increases the SNR (signal to noise) and gives me a relative gauge of how strong the sender is.  If I have my RF gain turned all the way down and still clearly hear the other station they have an extremely strong signal (9).  If I have to turn my RF gain all the way up just to copy then the signal is very weak, or faint (2 or 1).  In between those extremes I offer a relative report based on the signal strength  I  am hearing.

So, use the system as it was intended

So, reconsider how you give a signal report.  Think about the original intent of the R-S-T System and you'll be conveying far more information in your report that may help the other station know for certain how they are being heard.

I start most QSOs at QRP levels.  If the other station sends me a report that is below a 5 in readability or a signal strength 5 or below I change antennas or raise power, if I'm able, to make their copy of my station more pleasurable, but if they send me a 599 when they are barely copying me or losing me in QSB then how can I know to make a change?

Maybe this is a radical idea but for my own operation I will strive to start sending more accurate reports and help the other station truly know how they are being copied.


That's all for now...

So lower your power and raise your expectations

72/73
Richard, AA4OO

Tuesday, October 10, 2017

CW tone comparison C21 to KX3

The old ways are sometimes best

This is a short one.  I haven't found much time lately to enjoy the hobby, but the past few evenings I've been firing up the old Ten-Tec Century/21 and just listening to CW while I tend to other duties.   Tonight, I managed to find time before dinner to have a brief ragchew with fellow SKCC member WV8DH (Dave in West Virginia) using my old rig.  It reminded me how much I enjoy the sound of CW coming out of that radio.



I was too lazy to set the camera up to capture the QSO, but after the QSO I dropped down the band to find a good ragchew going on and grabbed my smartphone and shot a quick comparison of the CW tone presented by the 40 year old TenTec radio and my new, modern, Elecraft KX3. 

After listening to the video I realize that a lot of wonderful sound, including harmonics are not captured by the microphone on the phone and can't be heard in the video.  Nonetheless, I think you'll agree that the older rig has finer CW audio. It's certainly more pleasant to listen to for long stretches.  The KX3 audio still wears me out if I operate more than an hour.  I wrote a detailed post comparing the KX3 to the Ten-Tec Eagle last year that pointed out what I believe the culprit of the tainted audio on the KX3.  The Eagle is presently off the desk and if anything the older Ten-Tec Century/21 sounds even better than the newer Ten-Tec Eagle.

But here's the brief, badly made smartphone video comparison of the C21 and the KX3...

Comparing CW tone from TenTec C21 to a modern Elecraft KX3

That's all for now.  I'm going to be reviewing a nice bug that a friend has loaned me soon.

That's all for now...

So lower your power and raise your expectations

72/73 Richard  AA4OO

Sunday, March 26, 2017

More power to you with the Elecraft PXA100

When 5 watts is not enough

Gasp!  My blog is called "HamRadioQRP"... so what sort of heresy would lead me to post a topic on using more than 5 watts...
Will I have to turn in my QRP card?
I bit the expensive bullet and bought a used PXA100 amp for my KX3 this past week. There, I've got it off my chest.  I've come out of the closet. Go ahead and unfriend me and unsubscribe from my blog...

Normal Elecraft KX3 -- Notice the RF scale goes from 1w up to 12 watts

Elecraft KX3 with a PXA100 -- note the RF scale now goes up to 110 watts

OK, for those still reading...

This is my first time into the bottom of a solar cycle running QRP

If you've been operating for the past 6 months I'm sure you've noticed the band conditions have been getting pretty poor, and while I continue to try and make contacts and have ragchews using QRP power levels sometimes I feel bad for the other fella who is not QRP struggling to copy me.

I enjoy the challenge of making contacts at QRP levels but I also enjoy exchanging more than my call and an RST.  When the other station gives me a 559 or worse, or the QSB is getting bad I want to give them a few more dB to work with.  

I've written before that QRP operators can be compared to certain persons with dietary habits.  Sometimes vegetarians will eat dairy but if your vegan then you're abstain from anything that didn't grow from a root.  Well I'm more of a QRP vegetarian who will occasionally put a slice of bacon on my sandwich if I think it will improve the taste.  I'm certainly no vegan when it comes to operating QRP alone.   I've used my TenTec Eagle and TenTec C21 to go beyond 5w when the mood struck and in the case of SSB I've rarely operated at QRP levels with success so there I'm usually running well over QRP levels but I'd pretty much stuck to QRP for CW until recently.

Elecraft PXA100

Elecraft makes some very elegant equipment.  The KX3 by itself, running on internal batteries and with a built-in auto-tuner is an amazingly portable and full featured QRP rig.  With the newest version of firmware (MCU 2.70 / DSP 1.49, 2-27-2017) the KX3 will produce up to 15 watts of output on 80m, 40m and 20m when used with an external 13.8v power source, but if you want more than that you need an external amplifier.

I've been reading lots about the Hardrock 50 external amp and had even bid on a couple of Ten Tec 405 QRP amplifiers (which I lost) recently.  The Hardrock 50 was compelling for the price because it could be built with a full QSK option, whereas the old TenTec 405 did not have a full break in option but both would get my output up to 50 watts which is about 3-5 dB more output than the KX3 on it's own. 

But my normal operating mode is to begin at QRP and if that's insufficient I turn up my power.  In the case of most external amplifiers I would be over driving them if I kept the KX3 at 5 watts input to the amp.  It would require dropping my KX3 input power to the amp and fiddle with the output until I was at the power level I wanted.

On the other hand, the Elecraft PXA100 is fully integrated with the KX3 and I can simply turn up the power knob of the KX3 and when the power exceeds what the KX3 is capable of on its own the PXA100 electronics take care of adjusting the KX3's input into the amp to give me a smooth power output up to 100 watts.  Additionally, when using the internal tuner option with PXA100 I can use two antenna outputs from the PXA100 and switch between them using the ANT button on the KX3 while the PXA100 tuner maintains independent tune memories for each antenna. It is a very slick package but an expensive one.  Purchasing a used KX3 and PXA100 together puts you well over the $2k mark which you can certainly find more full featured 100w desk radios in that price.  So for price conscious hams this is not a sensible option.  I won't argue that this makes sense from a financial aspect, but I did it anyway.  Given the vibrant used market for ham equipment I wouldn't pay new prices for these but it still comes out to be a pricey desk rig even when purchased used.





OK, back to the PXA100.  One absolutely brilliant aspect of the PXA100 when using the internal tuner option is that its tuner seems every bit as good as the KX3's internal tuner.  I think it will tune a spoon on 160m (admittedly I haven't tried that).  It has no trouble tuning my ladder line fed attic Doublet which has some serious impedance mismatches on certain bands, so being able to quickly switch between my attic doublet and my outdoor Windom has been a real boon that I don't think other desk rigs can match with their internal tuners.  I could be wrong, but Elecraft's tuners and super fast matching algorithms are pretty much legendary in the industry.



Another nice thing about the KX3/PXA100 combo is that full break-in QSK is maintained and there are no fans. My shack stays very quiet (I hate fans).  The amp has a massive finned heat sink on top that while getting quite warm to the touch has not become overheated even on extended transmissions at 100w into non-resonant loads.  I still haven't delved into digital modes but I'm confident that while the KX3 struggles to maintain its cool when used for full cycle modes at 5w and above, when used with the PXA100 this combo avoids that problem because the KX3 is only running between 2-3w intput into the amp and can dissipate its heat at that level with no problem.

So for the past week I've been using this combo and I'm quite pleased.

Here is a video that I made today in a contact on 30m where I started at 5w and moved up to 25w and switched antennas during the QSO.



So lower your power and raise your expectations, but when expectations fail, use an amp

Richard AA4OO
http://hamradioqrp.com

Saturday, February 4, 2017

Over the waterfall

Situational awareness 

After reading all the hoopla surrounding the ICOM 7300 with its nice touch screen and waterfall/spectrum display, it got me to thinking that I was missing out on something.

HDSDR display on 40m tonight

When I first got my Electraft KX3 I hooked it up to HDSDR running on my PC and played around with the panadapter display. I admit it is very cool to visualize signals on the band.  That 44kHz view shown in HDSDR covers a large portion of the commonly used CW band segments.  I'd click on a signal and bam there it was tuned right in. I'd listen for a while and click another, and another. It was like shooting fish in a barrel (although I admit I've never tried shooting fish in a barrel).  After a while the novelty wore off and I went back to just tuning around the band.

There seemed to be more magic in stumbling upon someone calling CQ than looking at the bandscope and choosing the strongest signal.

Taking it all in


But I'm starting, just starting, to be more interested in working DX and potentially doing some contesting this year and for that I can definitely see an advantage to using a panadapter with the radio to see what's around me at a glance. 

However, as you may have read, I prefer using my TenTec Eagle over my KX3 at the desk.  But my Eagle is an older model made before the panadapter output came standard and even before they offered a provision for hooking one up.

My friend AA4XX uses a separate SDR with a input splitter and a DX Engineering RTR-1A receive interface to switch the SDR out of the chain when transmiting. The advantage of his solution is that it works with any transceiver but the relay in that unit is quite noisy and I appreciate the quiet full QSK offered by my radios.

Using a SDR as a receiver
protected during transmit by a DX-Engineering RTR-1A

One option for an older Eagle like mine is to take the input for a SDR straight from the input of the Low Pass Filter. That line is switched out on transmit by the Eagle to protect its own receiver so no separate switching circuit is required.  There's a tiny coax that would need to be spliced into which Paul assures me is doable mod with the right equipment. I would still need to buy an external SDR and it should be a good quality one or there's little point.

So I've been operating my KX3 at the desk this week using its built in RX/IQ to feed HDSDR to see if I like the idea enough to spend the money on doing this for the Eagle.  It's been over a year since I had this setup and I've switched computers so I had to go throuth the setup again and I thought it was worth documenting in case there are others that want to do this with their KX3's.

HDSDR is a really nicely done program, doubly so because it's free. It can be fed from an SDR or from your sound card. It interfaces to the control the radio using Omni-rig software.

So the setup is in two parts, configuring Omni-rig and secondly configuring four your sound card.

Omni-rig

Omni-rig is freeware CAT control software.  In the case of the KX3 it interfaces using the USB control cable that comes with the KX3.  Simply choose the serial port that your computer assigned to the KX3 and match the baud rate settings in the KX3. 

omni-rig settings for my KX3

HDSDR configuration

Download HDSR.

Configuration for the KX3 is mostly straightforward. Click the options button HDSDR.  The only part that trips me up each time is configuring the CW offset in [RF Front end configuration]. Make note of your side tone Hz setting on your KX3 by pressing and holding the CMP/PITCH button. Also be sure that you haven't inadvertently set CW reverse on some bands because that will really have you pulling your hair out as you try and figure out why the signals line up on some bands but not others.

So to set your CW offset correctly put your sidetone Hz as a negative number in CW_L and subtract your sidetone from 1000 Hz and put that value in CW_U as shown below.  Everything else should be set as shown.

RF-front end configuration screen

Choose the Omni-rig configuration as shown below to match your station settings.

CAT to radio settings

Lastly make sure RX/IQ output is turned on in your KX3 by setting MENU: RX I/Q to ON.  Run the KX3 RX/IQ cable to your mic input on your PC.  Then  choose your sound card bandwidth setting in HDSDR.  I'm not sure what the available bandwidth from the KX3 RX/IQ actually is but on all the PCs I've tried it with a bandwidth of 44100 seems to work best.

soundcard bandwidth

That's basically all there is to it. If you see a bunch of "lines" in the waterfall display that do not correspond to signals and if there is a thick signal line right at your input frequency then your station grounding is insufficient.  See my article on grounding.  When I first set this up I had insufficient station grounding and saw a lot of artifacts in HDSDR that were due to bad grounding between my PC and the radio.  So it will let you know if you have grounding problems.

So if you're lusting after that pretty display in the IC-7300 and don't want to shell out for another shiny toy, you can at least get a pretty display out of your KX3 without buying a PX3.  Just use HDSDR and the built-in RX/IQ.


That's all for now...

So lower your power and see the signals in technicolor

72/73
Richard AA4OO

http://hamradioqrp.com

Wednesday, January 25, 2017

Hard fought SKCC QSO using the Ten-Tec Century/21

Sometimes you need to move your QSO

My ever changing station configuration
Left to right - Elecraft KX3, Ten-Tec Century/21 with Ten-Tec Eagle on top, the MFJ 493 keyer on the right
4 keys - Navy Flameproof, Kent Hand Key, Vibroplex Bug, N3ZN QRP paddle
The Elecraft AF1 audio filter is sitting unused in front of the Century/21
After starting our QSO the ARRL QST program started right on top of us causing QRM that forced us to move to another frequency
My old Ten-Tec Century/21 is a lot of fun to use and its direct conversion receiver makes CW sound beautiful. But the frequency dial is fairly imprecise so when I asked the station to QSY up 1kHz finding him again was a bit of a challenge.  When I heard him I had to zero-beat him again to make sure I was on the correct side of the direct conversion receivers passband.

Enjoy the QSO and the QRM dodging...



Shooting this video

This video was a bit harder to shoot than what I normally do.  I usually place my camera to one side but I wanted to use my fisheye lens and shoot the QSO from above.  

While shooting I was straddling the tripod with the camera right in front of my face so I was reaching around the tripod to use my keys and get to my keyboard for logging.  It was a bit awkward, and in the video you'll see me bump the VFO while trying to operate the radio because I couldn't really see what I was doing.  It's always fun to add a level of difficulty while making these videos.


That's all for now...

So lower your power and raise your expectations

72/73
Richard AA4OO





Saturday, January 21, 2017

Quirky Keyer - The MFJ-493

The MFJ-493 has some cool tricks and some not so cool flaws

MFJ-493 "Super" Menu Driven Memory Keyer

Memory keyers do the repetitive and boring stuff

The bands have not been kind in this declining sunspot cycle and I've been sending out my call repeatedly on occasions before receiving a response.  I wanted to get a memory keyer to lessen the burden of repeatedly sending my call and to also give me opportunities to do a bit of contesting this year.

If you want a good memory keyer, the K1EL Winkeyer is the natural choice to go with, so of course, I chose to acquire a 23 year old MFJ product instead.   

Take the road less traveled and you'll find wonders or fall in a ditch, I always say

The MFJ-493 is no longer sold but you'll frequently see them available used for reasonable prices and MFJ still sells a less featured variant (the MFJ-492).

Memory keyer at the the ready

Features

Typical of many memory keyers the MFJ-493 let's you store messages in up to 8 memories of 4,000 character each using your paddle, an external keyboard plugged into the back or a terminal program via the serial interface.  If you make a mistake while entering a message you can send 8-DITS and it will erase the previous word and send the last word in the message so editing is fairly easy.  Messages can be constructed from other memories, i.e. you can store your call in Memory #1 and then use "/1" in other messages to reference your call.  Repeats and timers are available within the messages as well.

Any of the 8 messages can be sent with the press of a button, although to send messages 4-8 you switch to the second bank of memories.

I won't list all the features because I think they are relatively common across memory keyers and I've posted a link to the manual later in the post, but I will mention that I enjoyed the ability to vary the character AND word spacing sent in messages.  So you can create "Farnsworth" type messages that sound (to my ears) far more natural than the typical "squashed" sounding CW sent from most memory keyers.  I demonstrate that in the video review.   I know a contester would never want to slow down the CW sent from his memory keyer but I have different priorities.

Most of the functions are clearly visible on the front panel so you don't need to refer to the manual to operate most features.  Some of the commands are not listed on the front panel so don't totally ignore the manual.

Back panel
The back panel sports a couple interesting ports.. an external keyboard interface and a serial port interface.  The external keyboard can of course be used to generate Morse code without a paddle and can make programming memories easier.

The serial port can be used with a terminal emulator like PuTTY set to:

  • 1200 baud
  • 8 data bits
  • 1 stop bit
  • no parity
  • xOn/xOff flow control.


If you power up the keyer while it's attached to a terminal emulator you can see some interesting information:
MFJ-493 MEMORY KEYER VERSION 1.1.2C.        COPYRIGHT MFJ ENTERPRISES, 1993.
TYPE "[help]" (USING BRACKETS AND LOWER CASE LETTERS) FOR ON LINE HELP INDEX.
[help]
HELP INDEX FOR MFJ-493 MEMORY KEYER
1.  TYPE [help-program] FOR HELP ON PROGRAMMING MESSAGES
2.  TYPE [help-transmit] FOR HELP ON SENDING MESSAGES
3.  TYPE [help-setup] FOR HELP ON CONFIGURING YOUR MFJ-493
4.  TYPE [help-list] FOR LIST OF ALL COMMANDS
[help-list]
HELP-LIST INDEX FOR MFJ-493 MEMORY KEYER
[help]           LISTS GENERAL TOPICS
[help-program]   LISTS MEMORY STORING INSTRUCTIONS
[help-transmit]  LISTS TRANSMITTING INSTRUCTIONS
[help-setup]     LISTS KEYER SETUP INSTRUCTIONS
[help-list]      LISTS ALL COMMANDS
[start#]         STARTS KEYER MESSAGE NUMBER # STORAGE ROUTINE
[stop]           ENDS KEYER MESSAGE STORAGE ROUTINE
[{#}]            MARKS FILE FOR ASCII UPLOAD TO MEMORY
[send#]          SENDS MESSAGE NUMBER #
[show#]          DISPLAYS MESSAGE NUMBER # CONTENTS
[co]             STARTS KEYER COMMAND MODE
Among other commands.  There are also commands for printing out the contents of the memories.
So the keyer has a sort of built-in manual if you connect it to a terminal.  Very full featured at used prices.

Using a terminal to the keyer via the serial port also displays everything you send with your key as well as allowing keyboard (terminal) input to the memories or allowing you to send code by typing in the terminal emulator.

Lastly regarding commands.. a useful command to know that's not on the front panel, is that you can reset the 493 to factory settings by holding the menu button down while turning it on.


Cool features not seen in other memory keyers

Two functions FCC Exam Practice and QSO Simulator are lots of fun.  The FCC Exam practice sends a standard FCC CW exam from back when code was required for license upgrades.  It varies up the messages but sends the standard elements required back then.  Good for practice.

But the super-cool feature is "QSO Simulator". This mode performs an interactive QSO with you.

Are band conditions getting you down?  No one answers your calls?  Have a QSO with your keyer!

I'll leave the video to do most of the explaining but basically, the keyer will listen to you send CQ and answer your call and then exchange information with you answering after the turn around.  You're expected to get the call it SENDS you correct or it won't answer you back.  If you send poor CW it makes raspberry sounds at you.  It's just a lot of fun to play around with and copy.

MFJ-493 "QSO Simulator" demonstration




Nits

A couple features that are completely useless are the "hand key" mode and the "semi-automatic-mode".   Once the hand-key mode is enabled you can use either paddle as a straight key but it is very unresponsive at anything over 5-10 wpm.  So keep your straight key wired into the output of this keyer.  Similarly the "semi-automatic" mode is supposed to simulate a bug, where the DITS are sent automatically but the DAHS are manual.  Well it's even worse than the hand-key mode, don't bother as it's for entertainment purposes only.

Another problem with this keyer is related to the weighting commands 'C' and 'W'.  If you have either of them set to a value other than zero you cannot accurately record a message into memory using the paddles.

I'd hoped to be able to run both my paddle and bug into the input of this keyer and switch it to hand mode when I wanted to use the bug and use it as a bug "de-scratcher" but it doesn't buffer the bug input and in hand key mode misses about a third of the DITS sent by a bug so no joy there.  I'll just keep using my old Ham-Keyer as my bug de-scratcher.

MFJ-493 Manual

Many thanks to Paul/N6MGN for sending me a copy of the manual and schematic for this keyer so I could share them.

View manual
Download manual

View Schematic
Download Schematic

So many connections

Adding this additional keyer finally made me break down and build a connection box for all my keys and rigs.  I have 4-5 CW keys on my desk at any given time and 3-4 radios.  Each of the two external keyers have female RCA jacks for output.  The Ham Keyer uses 2 independent 1/4" inputs for straight key and paddle while the MFJ-493 uses a 1/8" stereo plug for the paddle.  The Ham Keyer expects the DIT to be the tip of the plug and the MFJ (by default) expects the DIT to be the ring of the plug.

Arrrgh!

To top it off, each of my primary 3 radios expect different wiring from an external keyer.  
  • The Elecraft KX3 needs a 1/8" stereo plug with the ring terminal un-grounded
  • The TenTec Eagle needs a 1/8" stereo plug with the ring terminal grounded or a mono 1/8"
  • My TenTec Century/21 needs a 1/4" mono plug (my rig is modified, I believe a stock C21 needs a male RCA
So I took a project box drilled it for 5 phono jacks wired in various configurations for each of the rigs and keyer inputs.  I still can't leave the KX3 key plugged in when not in use because when that radio is turned off it presents a high impedance on the plug and makes the C21 think the key is down...  (nothing is ever simple) but now I don't have a bunch of 1/4" to 1/8" and stereo to mono plug connectors chained together like a box-cars on a train.


Video review

This video review demonstrates a few of the features and contains the same QSO in the video above at the end...



Summary

The MFJ-493 is a feature rich yet somewhat flawed keyer.  For the price I think it's a good buy but don't expect some of the more esoteric functions to work up to your expectations.



That's all for now

So lower your power and raise your expectations... and send your call a couple dozen times using a memory keyer

72/73
Richard AA4OO