2022 Winter Classic Exchange, AKA 'CX' – CW Portion
CX Info: Classic Exchange CX
The following radios emerged from moving boxes, were briefly tested, and took turns on the modest sized op table: Hallicrafters SX-101 and SX-71, Drake 2B, Heathkit HW7 QRP, Homebrew WW2 Paraset Replica. They shared tabletop space with a WRL Globe Chief 90 and a Heathkit VF-1 VFO transmitter- which outputs 50-60 Watts.
The Antenna here is a HOA stealth 20M-40M fan dipole in the attic, about 25 ft above ground and surrounded by 1000+ roofing nails. There’s a bit of manmade noise on 40M. I am amazed that it works as well as it does.
Starting on Sunday- the SX-101 and Globe Chief TX combination worked well. After pairing the Drake 2B to the Globe Chief TX, it was discovered that 2B did not receive 40M. The required 3 Qualifying QSOs were made on 20M and then the 2B was swapped for the SX-71. Casual operating on Sunday netted a surprising 20 QSOs.
Tuesday's game plan was to qualify a Homebrew WW2 Paraset replica and a HW7 QRP transceiver.
The Paraset only operates on 40M. The TX is a XTAL controlled 6V6 oscillator and outputs 3.5W. The RX is a one tube Regenerative Detector with a second tube audio amp. It runs on a separate HV Power supply.
Transmitting with the Paraset the involves connecting the antenna, choosing the desired crystal, then key down to peak the Tank and Ariel tuning caps for maximum brightness of the two RF Power indicator lamps. RX involves setting the Tuning cap to match the desired freq as noted on a calibration chart or the RX frequency can be determined by listening on a separate receiver to hear the small signal from the Regenerative Detector. The RX tuning cap in conjunction with the Reaction control adjusts the RX frequency and the sensitivity. Each control affects the other. The Receiver is quite sensitive and somewhat selective, but the op must listen closely as there is a high frequency audio hiss present. The RX is easily overloaded by nearby higher-level signals. I was lucky to make 6 QSOs before a loud digital signal started up 5 KCs away.
For a small taste of Paraset info, see: #5 Valve QRP - Building a
Paraset - YouTube
Heathkit’s second worse ham radio product, the HW7 replaced the Paraset and 1 QSO was made before the 40M band died. Then 3 QSOs were made on 20M after the band woke up. . The HW7’s TX outputs 1.8W. The RX is direct conversion- which produces an upper and lower sideband signal. On 20M the VFO tuning is doubled, so a very small movement of the tune knob changes the frequency many KCs so it’s hard to precisely tune in a station.
It was very enjoyable to be able to make 34 Qs using no more than 60 Watts attached to a crappy antenna with ham radio sets 65+ years older than an IC-7300. Could ‘IC’ be the abbreviation for Ice Cold? As compared to the warmth and glow produced by vacuum tube radios? I think so, but YMMV.
The best CW signal I heard came from The Doc Spike Antique Radio Museum W7OS's XTAL Controlled Globe Scout 65. It possessed a distinctive chirp but was easy to copy VS other signals with too much chirp. An ARC-5 comes to mind. In this CX, I hit the Jackpot- to copy Jim W8KGI's many rigs all in a row. This year on 20M Jim offered up 6 combos. Also it’s interesting looking at the QRZ pages of participating CX ops to see some photos of the unusual or interesting equipment they reported using.
For my next CW CX event I’d like to have a second 50W transmitter- hopefully a homebrew. Thanks to all who participated.
Ricky KR7W
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