AmateurRadio.com

I just submitted my meager log from last weekend’s WAE RTTY test — just 45 QSOs and a whopping claimed score of 1,530. I only operated for a few morning hours (between 1125-1345 on Saturday and 1245-1700 on Sunday) in order to give DM780 a try at good ol’ fashioned 170/45 Baudot, a mode I haven’t worked since days of yore with the trusty old KAM and a terminal program. High time to give the new technologies a try, said I.

The DM780 + HRD Logbook combination did fairly well, considering HB9DRV himself says “HRD/DM780 is not contest software.” As such, there is no easy provision for sending or receiving QTC info for extra multipliers, and it wasn’t clear at first how to get DM780 to increment serial numbers in the exchange field (put them in [brackets], I finally discovered). Using a fresh database file for the log (as I do for every contest) lets me use the logbook’s Awards Tracking and Worked Status functions to keep an eye on what stations and countries I’ve worked on each band, but I have to be careful to individually set the other databases (previous contest logs, plus my master logbook) to not figure into the worked status lookups (this is one in the Logbook Databases control panel).

Another limitation from a contesting perspective is HRD Logbook’s inability to output Cabrillo files for log submission after the test, a feature that was available in HRD v4. So I have to use another app (SP7DQR’S nice ADIF2CABR freeware app) to convert an ADIF export file into Cabrillo format, and that only after doing a search-and-replace on the ADIF file to change the tag to that the conversion app is looking for. No biggie, I mud-wrestle data for a living, so this is just another day at the office…

That said… I’m familiar and comfortable with DM780 and HRD Logbook so it all worked just fine for me.

I worked the first day with the K3 in DATA A mode before remembering that AFSK A mode allows DUAL PB filtering to peak the mark and space tones. The DM780 waterfall screenshots below illustrate the difference far better than words:

K3 set to DATA A mode. BW = 400 Hz, Fc = 1530 Hz

K3 set to AFSK A mode. BW = 400 Hz, Fc = 1530 Hz, DUAL PB enabled

Note that the overall bandwidth in AFSK A mode is quite a bit narrower, even though in both cases the K3 was set to 400 Hz, and the distinct notch between mark and space tones is indicative of how effective this filtering mode works. Back in the pre-DSP days with the TS-930S and JST-135/245 transceivers and NRD-525/535 receivers, I used to use a Datong FL-3 audio filter which had a RTTY mode that accomplished the same thing, albeit at the AF stage.

DATA A and AFSK A each have their advantages. In DATA A (or AFSK A with DUAL PB turned off), I can open the bandwidth up and see a good portion of the band (I generally set DM780 to display 3 kHz on the waterfall and set the K3 bandwidth to match) and all the signals on the air, then select the desired signals with a point-and-click like I do in PSK31 mode. If QRM is a problem, I can crank down the bandwidth and shift the passband center frequency to pass only the station I’m working; once the QSO is complete, a quick tap-twist of the K3’s shift control recalls my wide settings and I’m back on the hunt. I rarely touch the VFO dial, all tuning is done with the mouse.

In AFSK A mode with DUAL PB enabled, however, the K3’s center frequency is fixed at 1530 Hz so all tuning must be done with the VFO. Also, the bandwidth is limited to 500 Hz max (which as shown in the image above is a bit less in practice, more like 250 Hz or so) making VFO tuning very touchy and slow (the 1 Hz fine steps must be used) and renders the waterfall useless for spotting other signals. But the filtering advantage is huge, especially in a contest scenario.

For me, it’s a no brainer — in the latter stages of the WAE contest I found myself using DUAL PB almost exclusively, occasionally switching it off and opening up the bandwidth if the band was quiet or if I’ve already worked the majority of the stations I tune across, since clicking on a waterfall makes it far easier to hunt and pounce.

DM780 facilitates the switch from narrow DUAL PB to wideband waterfall tuning easily: I first activate the center frequency marker (Tools>Program Options>Waterfall menu, or F8) and set it to match the K3 DUAL PB center frequency (1530 Hz). After finding a signal on the waterfall and clicking on it, I can then click the C button just above the waterfall to center it at 1530 Hz (HRD offsets the K3 VFO frequency to do this), and then activate the DUAL PB (press/hold the #6 key on the K3 keypad). The bandwidth is narrowed to 500 Hz, and the mark and space tones are perfectly positioned for decoding. To switch back to wideband, press/hold DUAL PB, and tap XFIL a couple of times to select the 2.7 kHz filter or use one of the filter presets to select my standard wide data setting of 3 kHz. This can perhaps be simplified to a one-button process using the new macro feature Elecraft just added to the latest firmware version; I need to check into that…

Note to K3 users: when working RTTY in AFSK A mode, either the radio or DM780 needs to be set to reverse, as AFSK A demodulates the lower sideband while DM780 looks for the upper. DATA A, however, works in the upper sideband.

In case you haven’t already heard, four of the operators of the C6APR station were tragically killed this week in a plane crash on their way to the station. Ward Silver, N0AX posted the following message to the CQ-CONTEST reflector, which I’m going to reprint here.

There have been several suggestions for on-the-air actions to remember the four ops lost on their way to C6APR yesterday. Perhaps a moment of radio silence – at the beginning of the contest or perhaps around the time of their flight. Or look back in your log to find the time of your most recent contact with them and take that moment out then. Maybe call C6APR at some appropriate time and wait for their signal. Putting a C6APR QSO in your log with a zone of 00 is another idea – I know that K7RA used show up in logs from the Pac NW for years after Homer’s untimely demise. Whatever seems appropriate to you, take some time out during the contest to not only remember the team, but to appreciate the other competitors. Let’s try to treat each other with a little extra respect this coming weekend as we’ve all just been reminded of how quickly a log can close.

73, Ward N0AX

eally slick thing is that as soon as you upload it, they do an immediate syntax check (so you’ll know if there are any errors), then post your claimed score on their website along with everyone else in your category.

I submitted as Outside Europe, Single Operator, Multi-band, low power and I guess I’m kind of in the middle of the pack at the moment. Of course, this is subject to log checking (I may have made an error logging a station or two) and it will change as others submit their logs, but it’s nice to get immediate feedback. Another excellent use of technology by the contest organizers.

One nice side-effect of just “playing around” in the contest was that I did not only work OH0Z on Aland Island on 75m, but as soon as I uploaded my log to Logbook of The World this afternoon I got a confirmation of that contact, bringing me to 97 countries confirmed on that band. I’m getting pretty close to being able to submit for the 5 Band DXCC award.

Posted via email from K2DBK’s Ham Radio Blog