Daily Archives: 1/25/2010

Goodbye QRP-L…

I subscribe to quite a few mailing lists relating to ham radio. A few months back, I decided to give the QRP-L a whirl. Unlike many lists like the EMRFD list, QRP-L had a fairly high NSR (noise to signal ratio), but hey, it’s a mailing list. It doesn’t take long to skip over stuff that doesn’t interest you. It’s not worth complaining that people spend more time talking about computer viruses and which sound card interface they use than actual interesting bits of homebrewing and QRP operation.

Today, I unsubscribed not just because it was boring, but because it is whining. Not just whining, but members seem to be piling on the idea that if someone doesn’t operate in a particular way that you approve, that they are entitled to maliciously jam your transmissions.

That’s illegal. It’s also first-order dyed-in-the-wool jackassery.

Goodbye QRP-L. It was nice knowing you.

On second thought, maybe it wasn’t that nice.

On properly operating a WSPR station…

Anyone who is subscribed to the QRP-L has likely been subjected to a long string of complaints against WSPR in the past week or so. This began with a generic complaint against a “consistent carrier” on 7.040. This rapidly decayed into a long series of rants against WSPR. Since I’m rather more fond of WSPR than the average QRP-L member, I chose to defend WSPR’s place in the ham radio universe.

But amidst the general complaints, there are a few points which they make which we should all take to heart. First of all, in the United States we are not allowed to operate automatic beacon transmitters below 10m. This means that you have to be in control of the station, and operate it in a manner consistent with Part 97 regulations. I’m not sure what that really means in the context of this mode, but I suspect that it means that running your beacon all night while you sleep isn’t actually legal, as fun (or useful, I would argue) as it might be to see those spots from New Zealand that occur at 4:30AM local time when you wake up and have your coffee. I believe that all hams should endeavor to operate their stations in accordance to regulations, so I think that we as WSPR operators should be at the control point of our stations when transmitting WSPR. I also think that this point of legality isn’t adequately emphasized in existing documentation, so new users of the mode may be unaware of this issue, so it would be great if we had a more prominent notice on WSJT’s site, and on wsprnet.org.

Beyond simple legality though, I’ve seen that the QRP-ers have some basis for being irritated beyond the mere legality of this operation. In the last 24 hours, I’ve logged one particular station who has operated at 100w output power, and for quite a while, was transmitting about 50% of all slots, including many back to back slots. This resulted in spots with a SNR of +5 over distances of 12000km. This isn’t a WSPR, it’s a rock concert. I think its good to keep WSPR at QRP levels or ideally QRPP levels. And let’s keep our transmit percentage down to 20% or less. As WSPR has become more popular (and it has become much more so even in the last few months, with dozens of stations on 40m and 30m) we’ll need to reduce the time we spend transmitting to mitigate collisions.

And let’s be especially careful around 40m, okay? 7.040Mhz isn’t the best choice of frequency, frankly. Lots of old time rock bound QRPers still claim it as their own, and while nobody owns a frequency, we should be courteous to all hams.

Another checker problem…

I was waiting for sleep to come, and surfed over to the American Checker Federation website. As long-time readers of this blog might remember, I’ve been tinkering a checkers program together, which I tentatively named “Milhouse” to play checkers. This week’s problem challenge was a classic 2 on 3 battle where White is to move and force a draw from the down position:

board

It’s late, and been a full day, so I can’t really say that I understand this position. But Milhouse doesn’t get tired: when I load the endgame database, it immediately proclaim that the position is a draw. What’s more is that it identifies two different lines: their website suggests 23-26 as a drawing move, but 19-15 is also a draw.

Without the endgame database, White thinks it is down a man, but with a 25 ply search can’t find the draw. In addition to the two moves listed above, it thinks that 23-18 is also almost as viable. But 23-18 is a dead loss, presumably because it allows Red to king both of its checkers. Even with the database though, Milhouse can’t seem to find the win for Red in a 31 ply deep search. This seems like a good test case for future improvements to playing with the database.