Sunday, May 15, 2016

Listen to the music

Comparing CW audio 

The Elecraft KX3 and the Ten-Tec Eagle

The bands were very poor today from my home and finding stations to operate were few and far between, especially at QRP power.  So I thought I'd take a break from operating and create a brief video demonstrating the CW audio differences between the Ten-Tec Eagle and the Elecraft KX3.



The radios

The Elecraft KX3 and Ten-Tec Eagle don't have much in common apart from having DSP architectures and both being from American radio manufacturers.  The Eagle is devoid of bells, whistles and has no-menus.  On the Eagle, what you see is all you get, as opposed to the KX3 which has multiple kitchen sinks stuffed into it's tiny enclosure. 


Setup

Both radios have their pre-amps off and DSP bandwidth set to 500 Hz.  I have the RF gain reduced by about 15dB on each radio since turning up the RF gain on a noisy day like today just makes for white noise.  

During the video I operated the NR (noise reduction) button on the Eagle to demonstrate how it makes a signal pop and in the same manner operate the APF (audio peaking filter) on the KX3.  I end the demonstration by reducing the DSP bandwidth down to about 100 Hz on each radio.  The Eagle has both 600 Hz and a 300 Hz IF filters so it gets a bit of insertion loss when I pass through the 300 Hz setting.  There were no adjacent signals so the IF filtering wasn't doing anything for either radio in this case.

The audio from the Eagle is coming from its built-in speaker, while on the KX3 I'm using an iHome external, self-powered, speaker.  The KX3 has an abysmal internal speaker and there's little point in trying to listen to it compared to a radio with a real speaker.  In my opinion that speaker is one of the few serious flaws in the KX3.  

After I shot the video I realized that there was a bit of a bias against the Eagle's audio because the microphone in the camera was below the top of the Eagle's case and thus wasn't directly hearing the cabinet speaker, whereas it was in direct view of the external speaker connected to the KX3.  The Eagle's audio sounds crisper than this in person when your ears have a straight shot to the speaker.

Subjective listening

Audio is a very subjective thing because people can hear the same thing very differently so I won't comment on my opinion on which I prefer.

I would however be curious to hear other's opinions.


That's all for now

So lower your power and raise your expectations

73/72
Rich, AA4OO

Tuesday, May 10, 2016

Twisted dummy

Improving the ugly dummy load

A few months back I built an ugly dummy load using the simplest method I could...

I soldered 20 2watt 1k ohm resistors across two pieces of romex wire and soldered it to a UHF connector.  Voila, had a 50ohm dummy load effective for extended QRP use and brief bursts of QRO power.  But as I analyzed the balun and noted in the previous post, some capacitance due to the simplistic design made it less than perfect at higher frequencies.

I got to thinking that the capacitance might be lessened by making those two antenna looking pieces of wire used in the balun into a different shape.

Croissant Balun

Twist and shout

So I twisted the parallel wires of the balun into a concentric loop  like a croissant and the result was promising.  Reactance is a bit less from 20m through 15m resulting in the SWR remaining as flat as my MFJ commercial balun.



Think like a Thermian - Never Give up, Never Surrender
Yes, I have an odd choice in favorite movies

So when you have a project that doesn't work quite as expected keep the little grey cells churning.  You'll likely come up with some alternatives. If someone who understands RF can explain to me why this helped I'd like to know. 

This ugly balun is going fellow Ham who is getting back into the hobby following a hiatus and is in need of a balun.  This balun is still not ideal but it's become more useable and the parts cost less than $10.


That's all for now

So lower your power and raise your expectations

73/72
Richard, AA4OO
http://hamradioqrp.com

Monday, May 9, 2016

Not all things are QRP

This is not a QRP antenna rotor

Another Saturday morning working at the Excalibur antenna site...  Dick (N4HAY) and I were doing more maintenance on the tower. Part of that effort was to determine why the mast rotor had stopped working.

Paul (AA4XX) and Dick had cranked the tower down and lowered it to ground the previous weekend to remove the beam and gain access to the rotor.  


Mast rotor is a prop-pitch motor from a WW2 aircraft

The rotor is an old prop pitch motor from a WW2 aircraft so it's both heavy and heavy duty but it wasn't turning the mast. The motor was firmly attached via a number of rusted and inaccessible bolts. At first we weren't sure we'd be able to free it from the tower but after an hour of copious application of WD40 and slowly working the blots back and forth we were able to liberate it to freedom.


Once the motor was free we saw that the thrust bearing for the mast was seized.  That will be addressed in a coming weekend.  Until then Dick tested the rotor on the bench and found it still functioning so that was good news.  


Dick recorded a brief video showing that the rotor was alive albeit moving a bit slowly with only 12v powering it.






Taking turns with QRPp

Dick and I took turns fighting the bolts holding the rotor while the other worked 40m using the 1Watter I built.   Band conditions weren't the best and we had the feed line to the doublet crossing some elevated counterpoise wires installed for the 160m antenna so antenna access to the 40m/80m Doublet wasn't ideal as we still focus our work on the shack and tower.

There was considerable DX chasing going on which made finding an opening in the narrow tuning range of the 1Watter a challenge.  I did managed a 559 report from a station in WV.  I managed some ?? responses from a few stations but didn't work anyone else.  I need to work on the feed line situation before using the 1Watter there next time.


That's all for now


So lower your power and raise your expectations


72/73

Richard, AA4OO

Friday, May 6, 2016

You have two ears but only one mouth

Listen more than you send

In honor of Mothers Day this weekend here in the U.S. we recall what our wise Mothers told us... 
Listen more than you talk because God gave you two ears but only one mouth
Learning CW is more about learning to copy what you hear than sending.  So listen, listen, listen.

Listening to on air CW QSOs using your own HF radio... 

Of course the best CW copy practice comes while listening to stations using your own HF radio and having on-air QSOs. So make the most of your opportunities to listen to live QSOs from your home station.

Find conversations that are at different speeds for your practice copy.  In my experience, when I only practice copying higher speed CW for a time, my ability to recognize slower CW gets rusty so practice copying all speeds.  I was worked by a station some months back when I was sending at only 13wpm who came back on the second exchange and replied that I was too slow to copy and he quit the QSO.  I don't want to be like that.  

Along with copying QRS stations, practice copying stations that are well above your comfortable copy speed in order to stretch yourself. You will likely miss much of the conversation but your ability to start recognizing common words and abbreviations will increase. Another side effect I find is that when I listen to a 25wpm (well above my present copy speed) exchange between two operators who have equally strong signals, I'll usually copy one station better than the other.  I try to figure out why that's the case.  Something about that operator's style is easier to copy and when I discern why that is, I try to emulate it.

I want to be able to copy all speeds of CW; both to encourage new QRS operators and ragchew with the QRQ old-timers.


On Air Practice

Listen to on air CW QSOs using remote radios

When you don't have hands-on access to an HF radio or when propagation is poor at your QTH web SDR stations are great resources for CW copy practice. 

Web SDR stations are accessible from http://websdr.org and allow you to listen to CW anytime you have access to the internet.   Web SDR stations are available from around the world, potentially from countries you haven't been able to regularly hear from your QTH.  So it allows you to hear different sending styles from around the world.


Web SDR station

Listen to machine generated CW

When live CW is unavailable you still have machine generated CW as an option.  Practice copy of machine generated CW is a pale comparison to actual CW QSOs but it has it's uses and it's always available.  The Morse Trainer App for Android devices offers most features standard in other learning applications plus a built-in list of randomized top English words and an e-book reader.

Morse Trainer app for Android


Sights and sounds

This following video demonstrates the copy methods above.



So listen more than you send and your CW copy, as well as your interpersonal skills, will improve with practice at listening.


That's all for now

So lower your power and raise your expectations

73/72
Richard, AA4OO
http://hamradioqrp.com

Tuesday, May 3, 2016

Beep Beep - No not the Road Runner

Practice sending CW

Let's turn back the wheel of time a bit.  This entry is about how I practiced Morse Code earlier in in my CW Journey.  

My first key was a MFJ-557 practice oscillator.  I used to set it on the center console of my vehicle and practice sending code while I drove when I first practiced for my General ticket 9 years ago.  

More recently I used it as my straight key when I restarted my CW journey 9 months ago.  I compared it to my Kent Straight key back in September.

MFJ-557 Practice key with a 2m/70cm SWR Power meter as a background prop

The practice oscillator doesn't have to be used with the less than stellar, check that, absolutely terrible, Philmore straight key attached to it.  You can wire the ocillator to other straight keys or any manual key providing a radio-free way to practice your code anywhere you wish.

However, practicing with paddles is more complicated and requires the use of an external keyer or a radio with an internal keyer set to not transmit.

Your electronic teacher

You may think you're the bomb when it comes to sending code but it could be that you are bombing out on sending code others can copy.  You need an objective critic.

Morse Code Reader App
I use the Morse Code Reader to check what I send.  It isn't perfect but it's a good portable solution to act as your Morse Code critic.

Demonstration

Here is a video demonstrating use of an MFJ-557 practice oscillator with your standard manual keys.  Additionally I address configuring your HF rig's built-in keyer to practice with a paddle.

NOTE: I mistakenly say in the video that I have the keys wired in series.  That's not correct. They are wired in parallel.




Practice, practice, practice

It is better to send good code than receive



That's all for now...

So lower your power and raise your expectations

72/73
Richard, AA4OO

Thursday, April 28, 2016

Just the medicine for lowering impedance

Pill bottle balun

Jack-WD4E is a fellow NAQCC member and he sent me one of his QRP creations that I just had to share.

If you are staying on your meds you probably have the perfect enclosure for a QRP Balun.

If I could save RF in a bottle...
Jack encloses his home-brew wound toroids in pill bottles.  
The child and arthritis proof cap keeps the goods away from young and old alike...


Just what the doctor prescribed...



So re-purpose your medicare paid goodness and put it to work for you

Sorry all you entrepreneurs, Jack told me that he's already applied for the patent so you won't be competing with Facebook with this product idea.  He owns it.


That's all for now

So lower your power and raise your expectations

72/73
Richard, AA4OO
http://hamradioqrp.com

Wednesday, April 27, 2016

QRP in many languages

Thinking Multicultural

Ham Radio and CW is used and heard throughout much of the world.  We live among many great cultures, each with their own language.  

I thought it would be fun to see the QRP motto in different languages...
I am a typical insular American and only know a wee-bit from languages other than English, so if the translations below are in-error blame Google translate.

Translations listed alphabetically


Chinese Simplified:
降低你的力量,唤起你的期望

Czech:
Snižte své moci a zvýšit vaše očekávání

Danish:
Sænk din magt og Hæv dine forventninger

Dutch:
Verlaag je vermogen en verhoog je verwachtingen


English:
Lower your power and raise your expectations

Estonian:
Alam oma võimu ja tõsta oma ootusi

Finnish:
Pienempi teho ja nostaa odotukset

French:
Abaissez votre puissance et soulevez vos attentes

German:
Senken Sie Ihre macht und wecken Ihren Erwartungen

Haitian Creole:
Senti pouvwa ou ak ekspetasyon nou leve ti moun

Hebrew:
להוריד את הכוח שלך ולהעלות את הציפיות שלך

Hindi:
अपनी शक्ति को कम और आपका उम्मीदें उठाएँ

Hungarian:
Alacsonyabb a hatalom és a raise your elvárások

Italian:
Il tuo potere di abbassare e alzare le vostre aspettative

Japanese:
あなたの力を下げ、あなたの予想を上げる

Klingon (note: Klingon's aren't really the "QRP type"):
HoS ghuS je pIHbogh laHwIj pep

Korean:
낮은 힘 및 인상 기대

Norwegian Bokmål:
Lavere makt og større forventninger

Russian:
Опустите ваши силы и поднять ваши ожидания

Slovenian:
Nižje svojo moč in poveča vaša pričakovanja

Spanish:
Baje su energía y elevar sus expectativas

Swedish:
Sänka din makt och höja dina förväntningar

Welsh:
Eich pŵer a chodi eich disgwyliadau


Guess which language takes the most letters to spell the phrase?  
If you guessed German you're close, but another language listed above beat it by one letter.



That's all for now

I drive an QRP Italian car (Fiat 500 Abarth) so...
          Il tuo potere di abbassare e alzare le vostre aspettative

72/73
Richard, AA4OO