The Spotless Callsign

Invisible Callsign Mystery

I'm a proponent for using the Reverse Beacon Network to determine how your QRP signal is getting out and for comparing different power levels and antennas. I look at how I'm propagating to reverse beacon stations and what signal strength was reported to know whether I should raise or lower power and whether one antenna is favoring another in a particular skip.

But after getting my new call on March 5th this year I didn't see any spots for my call on any bands. I knew my signal was getting out because I was easily working other stations.

I thought the lack of a spot might be due to my new call not yet being updated in QRZ, but even on the following day after QRZ had the FCC update I still had no spots in RBN.  I sent an email to the RBN administrator to ask if there was a filter or database that they used to prevent busted call signs that needed an update for new calls and they said there was not.  They told me if the RBN skimmer station saw the call it would be reported.  However looking at the aggregator configuration information in RBN there are a number of ways to configure filters but these are set on a station by station basis.  For instance a filter for known bad call signs is in there as well as an option filtering against the Super Check Partial Database which is a file containing the call-signs of active contestors. I'm not familiar with how a call-sign get's placed in that database but neither my previous or current callsign are in there.  So it appeared that there was no reason that I should be getting filtered from dozens of RBN stations that normally report my call.

Assistance from CWSkimmer creator VE3NEA

I then surmised that possibly there was some oddity about the CW Skimmer algorithm.  Being the inquisitive type I sent an email to the creator of CWSkimmer (VE3NEA).   He couldn't think of a reason that the skimmer wouldn't copy my call.  In fact, he said it should be easier for it to copy the dual letter calls than others. So we scheduled a CQ test where he specifically looked at the frequency I was sending my call on to see if CWSkimmer copied.   His station is about 570 miles from me so that's a good one-hop distance for 40m.  He reported that the skimmer saw my call and correctly copied it.  He sent me screenshots from his skimmer results.

See the text copied by the skimmer and the identified callsign in the right hand pane

AA4OO shows up in the cluster spot list

However, he noted that although the signal was clear and copied by the skimmer, there were no spots reported on RBN.  He concurred that it was strange and suggested we setup another test where he could watch what the RBN aggregator did with the call once it was passed on by CWSkimmer.

Hurrah, RBN has stopped throwing my call in the bit-bucket

Before I could schedule the followup CQ test with him, I was sending CQ on 80m.  The Reverse Beacon Network spotted me 11 times.  I tried a couple of other frequencies and power levels and sure enough RBN was once more showing spots for my station.

Hurrah, RBN has stopped throwing my call in the bit-bucket

80m propagation reports from RBN this morning

Spots from US, Canada and Europe (40m)... so I'm being spotted again

Still a mystery

So AA4OO is no longer invisible to the RBN but I'm no closer to understanding why the call didn't show up previously.  The lesson here (if there is one) is that if you have become invisible to the RBN don't assume your feedline has been cut by your XYL whilst trimming the hedge (this happened to me years ago) but rather some technical glitch has occurred or you've been blacklisted for being a LID, or aliens are sucking your CQ out of the ether.  In any event, it seems to self-correct so no-worries.  Keep calm and carry on.

Another lesson learned here was that other hams are extremely willing to help.  I think we have one of the best hobbies in the world because of the people involved.  So give back more than you take and you will make the hobby even better.

That's all for now

So lower your power and raise your expectations (and be patient)

72
Richard, AA4OO

Too Vain for N4PBQ

Just call me AA4OO

N4PBQ is now AA4OO

After getting my upgrade to Extra I wanted to get a new shortened call sign.  I wanted one that was more Morse Code friendly.  That means a couple of things to me.  One is Morse Code weight. That is a measure of how long the morse code elements take to send.  The site http://www.radioqth.net/cwweight will allow you to enter multiple call-signs to compare weight.

Call Sign	Weight
AA4OO	58
N4PBQ	64

The other factor was how complicated the actual Morse code letters are to send and copy, i.e. the dit-to-dah transitions.  I'm not aware of a calculator for this but my former call N4PBQ had a lot of dit-to-dah transitions in the PBQ suffix.  When other stations would send my call back to me they would really stumble over the PBQ so I wanted something simpler.  I've worked a number of stations with 'E' in their suffix and I find that hard to hear so I didn't want something like N4EE because people would miss the DIT or hear an I.

For the prefix, the letter 'A' is simple to send (just squeeze and release for paddles) and the letter 'O' while being long to send is likely one of the most distinctive and easy to recognize letters in the Morse alphabet.

For phone contacts it's also an easy one to say: Alpha Alpha Four Oscar Oscar

Thus AA4OO was chosen

Say it out loud in Morse and it sounds cool.

Play / Pause

Learn CW Online - LCWO.net -
Text to Morse Converter

Extra Vanity Call Sign Information

The website http://www.ae7q.com/query/ has excellent information on vanity callsigns and their availability.

I would have liked to have a 1x2 or 2x1 (i.e. A4OO or AA4O) call but as you can see using the website http://www.ae7q.com/query/ the 1x2 and 2x1 extra calls are completely taken for most regions and the competition is fierce when one comes available.

Changing call signs requires some updates

It takes about 19 days after applying for an available vanity call sign for the FCC to grant it based on some rather arcane rules that are described at this link. After the FCC assigns your new call don't forget to update your call on your LOTW account as well as any clubs you belong to.  The QRZ site will automatically update your call after a few days from its FCC database feed.

That's all for now

So lower your power and raise your expectations

72/73

Richard AA4OO (formerly N4PBQ)

The N3ZN Iambic CW Paddle

Behold... mechanical beauty 

N3ZN ZN-QRP Iambic Paddle (sporting my new call sign)

I re-entered the amateur radio hobby in the summer of 2015 after a bit of a hiatus.  To get my General license in 1996 a Morse code proficiency test was required.  At that time I had purchased a cheap MFJ practice key and a used version of the ubiquitous Bencher BY-1 paddle.  My Bencher was in reasonable shape but I just never became comfortable with it.  It always felt a bit imprecise to me and I wasn't happy with the width and size of its paddles.

When I came back to the hobby in 2015 as a QRP, CW operator I wanted a key for portable operation so that was my initial focus.  At the time, based on some fellow hams recommendations, I chose the Palm Single key which is an excellent, lightweight key for portable use that travels very easily because it collapses into its own travel case.  However as you can see in the videos in that review it's portable nature tends to make a bit imprecise and wobbly.  It works great for portable use but there are far better choices for a desk key.

I wanted a key suitable as the main station key but also easily travel with to operations where I'd have a desk.  So I didn't want a 4 pound immovable monster.  I wanted something small(ish) but stable and that's a tall order.

I looked at the eham.net reviews for keys and paddles and there were lots of good choices.  I narrowed it down to commercially available keys that allowed some customization.  Begali and American Morse both received favorable  reviews.  American Morse makes nice smaller sized keys and Begali makes works of art.  Both offered good choices but at greatly different prices.

Then I looked at N3ZN Keys.  Tony makes some very functional and attractive keys with a variety of build options.  One such option is the spacing across the outside of paddles (OTO).  My Bencher BY-1 paddles have about a 3/4" OTO spacing on the paddles and I have to consciously hold my hand open a bit wider than it naturally wants to be to keep from accidentally touching a paddle.  Tony offers different OTO spacing down to 1/2" which I found to be about perfect.  I also had a chance to physically try one of his QRP sized keys at my friend AA4XX's station and the light touch and precision feel immediately won me over.

So I went through Tony's online catalog and corresponded with him.  I chose a ZN-QRP style key with a red base.  The red paint contains some metallic bits to make it sparkly under bright light, not bass-boat sparkly but tastefully done.

Tony packs his product for shipment double boxed with more peanuts, bubble wrap, and foam than I have ever seen in any single container before.  The packing is truly amazing.  My key package could have been air-dropped (or drone dropped) onto my front walk and it would have suffered no ill effects.

ZN series iambic keys Specs

• All stainless steel screws
• Large 10-56 adjustment screws for both magnetic return and contact points ( the straight key uses 8-32 screws and a spring for return)
• Ball bearing lever return-3 ball bearings per lever arm
• Magnet lever return individually adjustable
• Lightweight aluminum 6061-T6 levers for QRQ operation
• silver contacts 
• Wired with 1/8" stereo plug
• Soft non-skid low profile rubber feet mounted with stainless steel screws
• 30 Day money back guarantee.  If you are not 100% fully satisfied then return item in its original condition and receive a full refund.  (You pay return shipping)
• carbon fiber fingerpieces- 3 colors

From the first long QSO it was obvious that I finally had a quality key.  The paddles just disappeared under my fingers and became an extension of my hand.  The lightweight aluminum levers combined with the carbon fiber finger pieces results in such a light touch that I kept wondering if I was actually operating the key.

Photo Gallery

This key is just too pretty not to photograph.

Carbon Fiber Finger Pieces 

Ready for Racing

Metallic Paint on top cap and customizable name plate no extra charge

Metallic paint on base, Aluminum levers and fine pitched adjustment screws

Pre-wired connections

"Houston, We have contact" Stainless Steel contact that is

With Silvered contact points

With the Siblings... QRP indeed!

That's all for now...

So lower your power and raise your expectations

72/73
Richard N4PBQ (soon to be AA4OO)

The Grand Illusion

Five by Nine... QRP... How can it be?

What does an S-Unit really mean and how can a QRP station sound like a 500w station?

The real gain doesn't come from transmitter watts

I rarely go up to the phone portion of the bands.  Since I started doing QRP and CW last summer I think I've only made two SSB contacts just because my focus has been CW.  But last night I was working on a bench project and tuned the Elecraft KX3 up to the phone portion of 40m for some entertainment.

A station in Rhode Island was testing his amp with a new antenna and was getting reports from various stateside operators.  There was a lull where no one was answering his CQ so I thought I'd give him a call.  He was peaking at S9 on my KX3's meter and he also sent me a signal report of S9 with some 10 over peaks.  I then told him I was a QRP station running 10 watts and heard the usual surprised reaction from a QRO station.

I gave him reports as he switched back and forth from running barefoot ~75w to his amp ~500w.  With his amp on he was an S9, running barefoot he was S8.  So the amp gave him one additional S unit.  In terms of hearing him I would have been hard pressed to tell much difference simply by volume.  He was perfectly copyable without noise with the amp off.

We also did some tests with my station at reduced power (as if...)  At 10w-12w output I received a S9 to S9+10.  Reducing output to 5 watts netted me a S8 report and when I reduced to 1 watt (one watt) he was still able to comfortably copy me and I received an S5.  So with my station at 1 watt and his running 500 watts we could still converse via SSB.  Ladies and Gentlemen you don't need as much output wattage as you think you do.

He was running through a newly constructed homebrewed vertical while I was using my 80m OCF Dipole.  We didn't discuss what sort of radial system he had installed, but the difference in antennas was likely the deciding difference in our stations.  We were about 500 miles apart and his vertical probably had more low-takeoff gain than my dipole, or possibly more ground loss so I probably had better high angle gain on him for the short 500 mile skip.  I think the take-away from this exercise is that the antenna is generally the key rather than transmitter power.  If I can get 6 dB of gain from my antenna I have in essence quadrupled my effective radiated power.  Quadrupled?  Yes, Quadrupled effective output power.

Power and S-Units

You've probably heard it before but it's worth a refresher...  Our radio's meter display a measurement in "S-Unit".  To move the meter up one S-Unit the receiver must hear 6 more dB (decibels).  So one S-Unit is 6 dB.

A decibel is:

• A Power Ratio:  dB = 10 Log P₂/P₁
• A Voltage Ratio:  dB = 20 Log V₂/V₁ 

You increase 3dB each time you DOUBLE your power

That's worth repeating... 

You increase 3dB each time you DOUBLE your power.  So to gain one S-Unit you must quadruple your power.

So if you are running 100 watts, to gain one S-Unit using the same antenna system you must increase your power to 400 watts.  If you are running QRP SSB (10 watts) that is only 1.5 S-Units down from 100 watts.  100w / 2 (-3dB)  = 50w / 2 (another -3dB or 1 S-Unit) = 25w... etc.

Antennas offer the cheapest increase in dB

Note the statement above "using the same antenna system".  That's the key then isn't it?  It's easier to get 6 dB of gain from an antenna than from wattage.  A 40m doublet can offer significant directional gain especially when operated on higher bands.  Now unless it's rotatable you will be at the mercy of the directionality of its lobes but if you have trees or tall structures you can very cheaply string up a few dipoles oriented in different directions and for far less money that a 500 watt amp (6 dB).  If you can only have one wire antenna you may miss out on some DX in the antenna's nulls but you will have some stellar gain in the direction of the lobes.  Of course rotatable yagis and beams are the best but now we are talking about real money again.  I'm talking bang for the penny.  You don't have to buy a wire antenna.  Some Dacron rope or weed-eater line and some surplus insulated wire is all you need.  You can even make your own feedline cheaply from electric fence wire and insulators.

We have a great hobby, but there are so many aspects of it that sound like common sense when they really are not... like increase your power.

Increasing power gains you very little compared to a better antenna systems.

That's all for now.

So lower your power and raise your expectations (or your antennas)

72/73 (Note:  72 is a common substitute for 73 among QRPers... as in "not enough power for 73") 
Richard, N4PBQ

1 Watt and a Wire... in the Attic

You can't always get what you want, but you try sometimes...

Recently I've dialed my normal 5 watts down to 1watt (one watt, singular) for all my contacts.  To throw some water on the fire I've decided to use my attic antenna which weaves all around my metal ductwork and electrical wiring.   Mostly this was to prove a point to myself but it may be enlightening to deed restricted hams that they can use a qrp radio and an attic antenna successfully.

Key lineup... Palm Single (paddle), Vibroplex Bug (circa 1970s), Kent Hand key

It only seems pointless until you try

Calling CQ with 1w QRPp into a poor attic antenna isn't as pointless as it would seem.  I didn't have to wait long when calling CQ before I got an answer most of the time.  

Now am I going to bust a pileup with 1 watt ?  Possibly not but I think that my assumptions about both how much power I need and how big an antenna I need are usually out of proportion with reality.

1 mighty watt

My assumptions are often incorrect

I made QSOs on 30m, 20m, 17m and 10m this morning all at 1 watt.  The solar conditions report was not really fantastic, especially for 10m.  Yet 1 watt through the attic antenna bagged the only DX I heard on 10m.  I had a couple of other multiple exchange contacts on 20m, 17m and one good old fashioned 25 minute long ragchew on 30m where I received a 599 report for my one watt from Bob (NR8M) in Ohio.  Admittedly, Bob was booming in and we had good propagation to each other.

http://www.hamqsl.com/solar.html

Video

The recording below was number 4 or 5 this morning.  I wanted to post this one because I was working another QRP station in Arkansas (K5EDM) and we did NOT have great propagation to each other.  He was running 5w while I was running 1w so it was QRP to QRPp.  In the video you can see that I'm using some of the KX3's tricks to pull the signal up because there was a lot of QSB and noise (note the GEOMAGNETIC FIELD UNSETTLED in the solar report).  

I had the volume maxed and was using the RF gain control mostly.  I eventually had to turn on the preamp which really washed me in noise but I dropped the RF gain more and eventually switched in the APF (audio peaking filter) which performed magic on this contact.  Often I find that APF doesn't help but this time it made a big difference.

That's all for now

So lower your power and raise your expectations

72/73

Richard N4PBQ

The need for speed in CW

CW QSO speed statistics... 

As I continue on my Morse Code Journey I have been using a desktop application called Morse News to work on my code comprehension of natural language sentences for ragchew training. I set the program to send at speeds higher than I can copy to stretch me.  Presently I have it set at 26wpm character speed and 23wpm Code speed.  I can usually figure out what the news story is talking about but I miss a lot of the specifics.

I was a kid in the 1970s when Speed Racer was a popular cartoon

The need for speed

Currently I'm OK working up to 20wpm qsos as long as the other station has good spacing.  Sometimes I lose the thread or the specifics in a ragchew at 20wpm and I just ask them PSE AGN? 

In sprints I can copy a callsign sent at 25wpm to 30wpm if I hear it a few times but that's no good for real contests where you need to catch that call sent at 30-40wpm sent the first time.  My friend AA4XX has asked me to help him in multi-op contests but I know he is sending around 30wpm and I just can't hang there at this stage in my Morse Code journey.

Statistics show 25wpm is the magic number

So it got me to wondering what was the actual "average" qso speed.  I downloaded days of raw data from Reverse Beacon Network.  RBN collects the call sign, the SNR and the SPEED.  The raw files contained between 40 to 50 thousand CW CQ calls logged each day after I filtered out other modes.

The average speed from RBN CW logs worked out to exactly 25wpm.  The standard deviation was 5.34wpm which would mean most of the time you would expect to work stations between 20wpm and 30wpm.  That seems reasonable and matches what I seem to hear on air.  These numbers are from the CQ calls themselves and are only measuring character spacing speed so the code spacing is likely a bit lower in most cases and for ragchews is likely averaging 2 to 5 wpm lower than the actual sent character speed.  Since I am not much interested in serious contesting at this stage in my hobby going over 30wpm isn't on my radar.  

So based on those calculated CW speed statistics from RBN data if I can reach the point where I am comfortable in a 25wpm ragchew I should be content (for a while)

That's all for now.

So lower your power and raise your speed.... err expectations

72/73

Richard, N4PBQ

Race to the bottom

1 watt or less?

I've been considering ordering a 1 watter kit but I was concerned that it wouldn't be useful in the downward sunspot cycle. 

1Watter board with initial 100nf caps installed and starting inventory of other parts.
Not shown are the myriad toroids (fun, fun), transistors and pots.

So I spent some time this afternoon making 1 watt contacts on 20m and 40m with my Elecraft KX3 just to see what staying limited to that power would be like.  I've made casual 1w contacts in the past but staying at 1watt was a good test for me.

It turned out that I had a plenty of answers to my 1 watt CQ calls and received reports that were only one or two points down from my report to the calling stations.  The last station I worked dropped down to 300 milliwatts and I still copied him fine. 

So I ordered a 1 watter kit for 40m from Kits and Parts today.

The 1 watter kit is significantly more involved to build than the Elecraft kits I've assembled to date. I hope to learn a lot from the build and alignment and I just might finally have a reason to buy an oscilloscope (hopefully my wife doesn't read this).

Update 2/20/2016:
I received the kit yesterday.  It includes 21 100nf SMT capacitors that the builder "highly recommends using".  Optionally he supplies through-hole capacitors.  I tried figuring out hold to hold the SMT part in place to solder for about 30 minutes and gave up.  I don't have 3 hands. I'd have to have someone show me how to solder an SMT part.  Even in the linked video to building the kit the builder used the through hole components so I don't know why the SMTs were supplied or were highly recommended.  So I used the through hole capacitors. 

Through hole versus SMT capacitors

I couldn't figure out how to solder the tiny SMT capacitors

1watter board with the 21 through hole 100nf caps installed

Inventory of resistors

Next step was installing resistors.  There are six 1/8w resistors missing in the kit:

• R3,9,21,22 (470)
• R12 (1.2K) 
• R14 (4R7)

I haven't built enough kits to have spares like this so I sent them a note and will see how long it takes to get the resistors.  I haven't inventoried the rest of the parts yet but so far I'm a bit disappointed.  I have built 4 kits from Elecraft and one from 4-State QRP and all of those kits had all the parts.  Although in the case of 4-State QRP one of the plastic knobs was broken in shipment.  They sent me another in 3 days.

That's all for now. 

So Lower your power and raise your expectations

73/72

Richard,  N4PBQ