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Got the SoftRock v9.0 Lite+USB Xtall working last night.  I’m not 100% sure what the problem was, but I think it may have been due to me programming an ATTiny85 with the latest SoftRock firmware (V15.14), rather than using the supplied ATTiny45 with V15.4.  So, I’m sticking with old version for now.  Not sure if it was cockpit error on my part programming (more likely) or an incompatibility with the new firmware which is designed to work with the Ensemble series of SoftRocks.

As shown in the screenshot from Rocky above, there appears to be a spur that repeats every 1 kHz (see left side of the waterfall).  The right side of the waterfall is with the USB cable unplugged from the computer.  I’m 99% certain this is something internal to the SoftRock because I wrapped a few turns of the USB cable around a big type-31 ferrite toroid and the spurs are still there.  So, need to play with that.

I’m listening to a Es opening to the south on 50 MHz right now using the SoftRock as the RX IF.  Yes, that means that I got the RX on the transverter souped up a little hotter.  I will post something about that later today and place a non-causal link in this post.

I recently resurrected the 50-MHz transverter project and have made good headway getting it working.  On Friday night, I began the process of tapping holes in the PA module heat spreader.  But, despite using plenty of “cutting fluid” (3-in-1 oil), I managed to break a (well-used) tap on the first hole.  Since the maximum (linear) power out of the driver stage is 200 mW, I embraced my inner QRPer and put the PA project aside to give the transverter a try in the CQ WW VHF contest.

The 6-meter Yagi had come down in favor of Yagis for 222 and 432 when the loaner FT-736R showed up.  So, I scampered up onto the roof and moved Yagis around.  I had hoped that this moment would be accompanied by changing out RG-8 coax for LMR-600 and LDF4-50A that are taking up space in the shop and shack.  But, I was not ready to commit to cutting that and I still don’t have LMR-600UF for the rotator loops.  Plus, I should replace the rotator at the same time.  That amounted to too much work for the available time.  I really just need to bite the bullet and install a rotating mast for the VHF antennas that’s not so precarious.

Got everything hooked up late on Saturday afternoon, but had to tend to some domestic concerns and was QRT until later in the evening when I heard my neighbor W4EE calling CQ on six SSB.  Did not know that he had six!  Apparently, this is a new thing for him, too.  He was surprised that I didn’t vibrate his radio off the desk like I usually do!  Told him I was running 200 mW and everything made sense.

Ended up working a few other locals on Sunday including N3UM, who moved me from 6-meter CW to 2-meter SSB for a quick chat.  He just completed the N1DPM active bias mod to his Mirage B2518G, so was eager for an audio report.  Sounds good!  He said my B3016G sounded good on-frequency, but I haven’t gotten the mod actually inserted into mine yet.  Probably that Kenwood (TS-700S) audio making up for the amp’s inferiority…

Eventually, I will be posting more details on the circuit here.  This is one of those projects that I would not encourage anyone to duplicate as I have constructed it.  However, there may be useful features.

As I wrote previously, for 2011 Field Day, I made a game of trying to contact W3AO and KE3Q on as many bands and modes as possible.  Here are the official standings from KD4D who managed the PVRC competition:

So, K1DQV was at the top of the heap (with a 2-meter CW contact, I might add).  Anyhow, I’m quite pleased with the results and happy to report that W3AO is claiming the all-time high QSO total for Field Day this year.  Congratulations.

Early Monday morning, the day after Field Day, we welcomed our son Evan into the family.  We were so right to stay home!  As good friends have opined “your life will change…for the better.”  So far, I would tend to agree.  The blog will receive (even more) infrequent updates, K8GU may be a little less active on the air, and there will be fewer homebrew projects over the next few weeks and months.  A few months ago after building some UHF antennas when I pinched the palm of my hand with a pair of pliers, I watched the blood blister heal and commented to Sarah on how amazing it was for several days straight.  “You think that’s amazing?  Well, I’m growing new life inside of me.”  We laughed, but it’s very true.  Every day is something new:  grasping, gazing, grunting, and gurgling.  This is only the beginning.  That’s pretty amazing.

I had not been a big fan of Field Day for many years until last year.  Although ARRL technically terms it “an operating event,” it has most of the features and flavor of a contest.  But, the bands are crowded, there are a few more drunks and lids than your standard contest.  Your local club thinks it’s a great idea to put up a tower and an ancient tribander, but they only do a half-witted job of it making a lot of work for something that could have been smoked by a doublet in the trees. Or, you show up at a random Field Day site, introduce yourself, and offer to operate CW—only to be handed a J-38 or a blank stare.

Last year was different.  Sarah’s branch chief at work is a ham and she’s married to a ham.  Somehow, it came up that I was a ham and soon we had an invitation to Field Day at her mother’s place near the water of the Chesapeake Bay on Maryland’s Eastern Shore.  I was reluctant, but they assured me it would be OK.  They have a tower trailer for a triband Yagi and trees for dipoles on the low bands and they operate 1A.  It was fun.  Sarah enjoyed herself, too, which is a welcome change for a ham radio event!

For a variety of reasons (namely the impending birth of our first child), we elected not to go to the Eastern Shore this year.  After talking to a few guys at the PVRC/W3LPL open house last weekend who implored me to come to their operation (W3AO, the FD of epic proportions) instead, I decided I needed to do something.  Since W3AO was making a run on the all-time Field Day high score record this year, I opted to make a game of running 1D and working W3AO (and their GOTA station, KE3Q) on every band and mode available.  The goal was to not disrupt our weekend too much and to have fun, possibly contending for a plaque offered by PVRC for the most band/mode QSOs with W3AO/KE3Q.

Here’s how things shook out (yellow = QSO, blue = no QSO, red = no QSO possible with W3AO/KE3Q, hashed = no QSO possible with K8GU, but possible with W3AO):

So, I did pretty well with W3AO, all things considered.  I was not QRV on RTTY until Sunday morning (forgot that I did not set that up on the “new” PC yet).  By that time, I missed the really good opportunities to work them on 20 and 80.  I don’t know if I ever would have on 15 and 10.  I did see them spotted on PSK31 (a mode I will never enjoy—one QSO was enough) on 15, but could not hear (erm, see) them here.

It was a bummer not to have 6 meters here and despite 3-4 requests, the 2-meter phone operator(s) refused to QSY to CW with me, even though one told me I was his first QSO in an hour!  It did take almost 10 minutes for them to find a key to work me on 222 and 432 CW!  Thanks for going the extra mile!  I believe my total of 17 QSOs ties K3DI’s record, plus one more with KE3Q, for 18 total.

I worked KE3Q right away on 75 meters, but never heard them again.  I did see QRS Skimmer spots for them on 40 and 20 CW in the middle of the night and at the very end of event, respectively.  But, I do not believe they were QRV on CW on any other bands.

Having 6 meters and digital from the start probably could have increased my totals a bit.  A satellite QSO or two would also have been good.  But, I did not have it in me to get that set up in addition to building microwave gear and getting the baby’s room ready.  Plus the 432-MHz amp I bought recently has been held hostage by the deadlock between Canada Post and their workers.  So, I only have 10 watts on that band until that arrives, making the annual Field Day “Battle for Bandwidth on the Birds” that much more exciting with a small antenna oriented for terrestrial work.

It was a good time, although I think I’ll be itching to go out into the “field” again next year…thanks for the QSOs and the QSYs!

Brian, ND3F (aka N3IQ/R), gifted me a partially-complete SoftRock kit a few months ago on the condition that I put it on the air.  I’m making some progress on that.  I took this photograph to show the SparkFun USB break-out board installed in the Bud CU-124 enclosure.  The whole thing is assembled now, but there is probably a solder bridge somewhere.  This kit is going to be a lot of fun because it’s actually more flexible for experimenting than the present Ensemble II RX kit.

Apologies for the bad pun in the title.  I was going to call it “Microwave progress” but could help myself when I thought of this one.  Here are some notes from tinkering over the past few days.

1296 Mhz

After learning that the 1152-MHz LO power was -11 dBm, I inserted a MAR-3 MMIC on the 1296RSU transverter board.  W1GHZ shows an MAR-6 on his board, but the ever-astute N3UM noticed that the P1dB for the MAR-6 is 1 dBm, which is well below the nominal 7 dBm level of the ADE-5 mixer.  Unfortunately, the MAR-3 has about 12 dB of gain vs the MAR-6′s 20 dB.  A little bit of skullin’ lead me to my stash of SGA-4586′s (suggested as an economical front end by W9SZ), which can do >20 dB gain with a P1dB point of 16 dBm or so.  Perfect.

Unfortunately, with an 144-MHz IF drive of about 2 dBm, the 1296-MHz output was totally trashed with various mixing products.  I spent about 20 minutes searching frantically for the 3-dB SMA attenuator I’d purchased at Dayton.  But, I never found it—a sign that my organizational scheme has lost control or that I never actually bought the attenuator.  Either are possible.  So, I did the next logical thing—I added a Pi-network attenuator between the SGA-4586 “LO boost” MMIC and the ADE-5 mixer.  If the Dremel tool didn’t make it’s inventor independently wealthy, it should have.  The only SMD resistors that I had on-hand that were realistically appropriate (39.6 and 130 ohms) yielded about 6-7 dB of attenuation, so the effective gain of the SGA-4586/attenuator cascade was probably around 13-15 dB, yielding somewhere around 2-3 dBm of LO.  Blech.  That’s essentially the same as the MAR-3.  The 1296-MHz output with 2 dBm of drive at 144 Mhz was about 2.5 dBm.

The data sheet for the ADE-5 suggests that the conversion loss increases as the LO drive level falls bellow 7 dBm (shocking!), but there are not enough data to show how precipitously it deteriorates.  However, essentially 0.5 dB of overall power gain does not jibe with the amount of gain in the system, which should be closer to 20 dB.  From this standpoint, perhaps the mixing products were due to IF overdrive instead of LO overdrive.  In any event, about 3 dB (instead of 6 or 7 dB) of attenuation in the LO would be a good thing.

902/903 MHz

Fresh off my mixed success with the W1GHZ 1296RSU (which are neatly packaged in Hammond 1590BB-sized cast aluminum boxes), I wanted to give the 902/903 version (which is still loose boards) a try with the spectrum analyzer.  So, I hooked up the 756LO board first.  It made -5 dBm at 756 MHz.  These numbers are more like what W1GHZ was promising.  So, I put the MAR-3 mentioned above onto the 902/903 transverter board.  With 2 dBm of 147-MHz drive, the output was a very clean 16 dBm on 903.  Score!  Must be livin’ right at least half the time.  My last DigiKey order included a 1590BB for that transverter, but the 756LO board is a bit longer and I haven’t yet found a suitable case for it.

3456 MHz

Thought I was done?  Me too.

I admit it.  I’m a sucker for this sort of thing.  Fred, N1DPM, recently posted to VHFcontesting and the “Stanford” VHF lists that he was selling a bunch of spare microwave gear, including a first-generation DEMI 3456 transverter/LO and some amplifiers to get the output up to 4 watts.  Cheap.  He had some 2304 stuff, but ye old project fund is pretty much depleted since Dayton and I always try to keep a little bit in reserve for just this sort of opportunity.  Anyhow, the transverter is set up for 10 watts of drive on 144 MHz.  I gave it 250 mW (24 dBm) from my modified IC-290A (post to follow on this—not rocket science, just bypassed the PA) and the output came up at -9 dBm on 3456 MHz.  Once I remove the attenuator from the input, I should be able to get it up to about 13 dBm.  At least it seems to work on TX.  Need an antenna to try RX because the K3UO beacons are not as close as W3APL.