QRP SIG

QRP Notes: Communication Technology
by Jim Henry KE6WGO

Technology keeps marching on. Each year will see continued improvement and change in amateur radio. Personally, I think the internet helps amateur radio progress. Here are a few examples.

It’s only been 3 years since the PSK31 narrow band digital mode was first conceived by Pawel Jalocha SP9VRC. Many improvements and ports to specialized DSP processors occurred before it evolved to it’s present form on the common PC SoundBlaster card. I first heard about it on the QRP-L list server(1). Last year saw exponential distribution of Peter Martinez G3PLX’s software throughout the world. The 8th version of this excellent communication software is available through the PSK31 homepage in Spain(2). In January, 2000, a new program called DIGIPAN was released on the same site. Listen on the air, and you’ll find almost every PSK31 station is trying it. It’s chief advantage is a wider waterfall display that lets you see the full SSB audio bandwidth. This eliminates the tunnel vision of the earlier program, and makes it easier to find and tune in a PSK31 station. PSK31 is a natural for low power (QRP) work, and efficient use of bandwidth (100Hz spacing between stations).

It’s one year since the NorCal-20 was first released by the Northern California QRP Club(3). The internet played a great part in connecting designers and beta testers during the initial development that preceded the production of 1000 kits. The internet also provided the means of exchanging ideas, schematics, and assistance between hams all over the world as they assembled and refined this excellent 20m transceiver. Recent articles by Gary Surrency AB7MY and Dave Meacham W6EMD in the NorCal publication QRPp compiled the full set of recommended modifications to this design. Most of these mods first appeared on the QRP-L email reflector. Penciling these into my schematic, I see about 10% of the circuitry changed. How long does it take to improve the last 10% of a design? In this case, about one year effort by scores of hams all over the world.

The Elecraft K2 10-160m CW/SSB HF transceiver continues to improve and develop with excellent on-line support from its designers(4). I’ve been astounded how many Europeans have purchased these kits and now have them on the air. In large part, it’s due to the accessibility of the designers and their willingness to solve problems using the connection provided by the internet. The K2 noise blanker worked well here in the states, but showed problems in the megaWatt RF environment in the neighborhood of European SW broadcast stations. Peter Zenker DL2FI, founder and publisher of the QRP-Report, writes in the DL-QRP-AG email reflector(5) that he is very pleased with Wayne Burdick N6KR’s immediate response and efforts to solve this problem for the European hams.

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73 de Jim KE6WGO

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