Grrr! A ‘Solar’ PBMME this time!

By , February 27, 2011 1:27 am

Saturday February 26th was the February running of the QRP Polar Bear Moonlight Madness (PBMME).  It was overcast with a light wind, the wind chill was -13°C (9°F).  Michael invited me to join him at the Super Secret Location (SSL #2) in the Central Experimental Farm.

The Solar

This past week I received a backpacker solar panel kit from Modern Outpost.  I am very impressed both with the kit and with the company!

… So I was keen to put it through its paces!

There wasn’t much sun on Friday so the Novuscell 25Wh battery was about halfway charged up.  I noted that the battery voltage was 11V.

I charged it from the mains and when it was full, the battery voltage was 12.5V key up and 12V key down, producing 2.2W on 80m, 2.5W on 40, 3W on 30m and 2.5W on 20m.

I’ll be interested to see how long 6600 mAh lasts with the KX1 :mrgreen:

Antenna Stuff

Dapper Bear with the Flag

Dapper Bear with the Flag (TNX Jean for the Flag!!)

Dapper Bear was already at the Super Secret Location #2 when I arrived.  Michael had an inverted-vee dipole set up and he was using his K1 on 17m and 30m.

I set up a W3EDP in an inverted-L configuration with two counterpoise wires, a 16′ and a 36′ wire.  I was interested in characterizing the differences between these two counterpoise lengths.  I connected the Novuscell storage battery and hooked up the KX1 to the antenna and then I made some measurements:

36′ Counterpoise Measurements 

Band SWR
80m 6.5 : 1
40m 1 : 1
30m 1 : 1
20m 1 : 1
16′ Counterpoise Measurements 

Band SWR
80m 2.2 : 1
40m 4.5 : 1
30m 1 : 1
20m 1 : 1

The Bears

VA3SIE with the Flag

VA3SIE with the Flag (Thanks Jean for the Flag!)

So… with the 16′ counterpoise, the W3EDP doesn’t match too well on 40m.  What about with the 36′ counterpoise? … well, it matches well on 40m but not on 80m.  So I guess I need to switch from one counterpoise to the other.  On 30m and 20m, the KX1 tuner matched 1:1.

But is there any difference in the far field signal strength between the two ??

My first contact was with Scotty N0AZN Polar Bear #266 on 20m.  I had the 16′ counterpoise connected initially.  Scotty could tell that someone was there but after about 5 attempts at getting my callsign, he sent SRI… could not pull any part of my callsign out of the noise.  So I disconnected the 16′ counterpoise and connected the 36′ one, retuned and called again.  This time Scotty was able to get VA3.  After another couple of resends he had my full callsign.

So:  Scotty was hearing me better with the 36′ counterpoise.  Does EZNEC agree?

EZNEC Comparison 16' vs 36'

EZNEC Comparison 16' vs 36'

EZNEC does indeed predict a 2.5dB difference in the far field signal strength, the 36′ being stronger than the 16′ counterpoise (even although both are lying along the ground).  I should compare the two counterpoise lengths on other bands also!

Scotty gave me an RST 249 from the ice shelf in Lincoln, Nebraska.  I was very pleased to have made at least one QRP Polar Bear contact, I was thinking that my late start may have meant missing all the other bears.

CQ PB CQ PB de VA3SIE/P !

CQ PB CQ PB de VA3SIE/P !

After the QSO with Scotty I called CQ for a while on 20m and when no one came back I scooted down to 40m and the RTTY wasn’t bad at all so I parked on 7039kHz and started calling CQ over the Odessa single letter beacon.

Shortly thereafter Gary K8NYG in West Virginia came back to my CQ call.  Gary wasn’t a polar bear and I wasted no time in letting him know what the Polar Bear activity was all about.  We struggled through the 40m QRM and completed a pleasant QSO.

I went back up to 20m and called CQ for a bit on 14.060MHz and then I got 2 calls at the same time.  I asked the weaker of the two to come back to me first, it was Mitch NA7US running 3W from the foothills of the Cascade Mountain Range.

I had another ham start calling ‘CQ’ without any ‘QRL’ with a very strong signal, and it made life tough.  I send QRL QRL QRL and then we got back into the QSO.  It got dark while I was chatting to Mitch and the wind got stronger… I was starting to shiver.

After Mitch, I called in Dennis KB7ST who was patiently waiting.  Dennis had seen my spot on qrpspots.com.   I enjoyed a few minutes of chatting with Dennis then I got a loud carrier which wiped him out.  I sent QRL a couple of times.   Then the carrier again – *OUCH*, my volume was up full to pull in Dennis’s QRP from the other coast so it *hurt*.

It was snowing hard near Seattle this afternoon – real *POLAR* weather :-) .

I dialled the KX1 filter down to its narrowest but the constant carriers were very troublesome and after a few more minutes of chatting with Dennis, it was too much and I had to say 73.  Desnnis’s QRPSPOT says it all:

 

QRM ended it

QRM ended it

After Dennis, I went back to calling CQ but the carrier kept popping up sending the occasional super-strong dah.  It was so strong that I had to keep dialling down the volume to protect my ears from pain.  It was very frustrating!  Finally a VE3 called me (I think) but I had the volume down and I was distracted and missed his call :-? .  I did ask a couple of times QRZ but he didn’t hear me.  Oh well…   maybe next time.

By this time, I was getting way too cold so I decided to pack it up for the night.  All in all a very enjoyable PBMME, and I got at least one bear in the log – yay!

Log

Time Band Callsign Name SPC RST In RST Out Notes
2205Z 20m N0AZN Scotty NE 249 569 Tough Copy but we got there in the end for a BSO!
2315Z 40m K8NYG Gary WV 529 569 Some QRP from tuning up on freq.
2345Z 20m NA7US Mitch WA 569 569 Tough to coordinate QSO but we got there…
2315Z 20m KB7ST Dennis WA 549 579 Nice 2nd 2XQRP QSO into WA tonight…

2 Responses to “Grrr! A ‘Solar’ PBMME this time!”

  1. Mitch Gill says:

    Martin,

    Awesome! Glad to have been a part of this and now know about qrpspots.com. I am using a 3 element bobtail but it is oriented N and S right now for a test so I was suprised that we got to chat. Do you QSL? Would you like a QSL?

    Mitch

    P.S. I dont think I could have handled operating in that weather. Great job and hope to catch you again on the air.

  2. va3sie says:

    Hi, Mitch.

    Glad to have worked you. My pile of unanswered QSLs is already big enough ;-) … one of these days I will get to it. It was a fun QSO. qrpspots is also on twitter for when you’re out mobile… :-)

    73
    Martin.

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