VE6AB Technical
Blowtorch Radio
Being a ham, and always enjoying old radios, and in particular short-wave radios, I have a number of them in my collection, including a Sony Earth-Orbiter CRF-5090 of 1975 vintage, acquired when I was a young guy working in the Seismic industry.
At the time, and when the crew would spend the winters in a camp located in northern Canada doing sesmic exploration for a client, the only form of entertainment while far removed from civilization was a short-wave radio.
It was cool to see all the various shortwave radios in camp, as with aproximitly 35 guys on a typical seismic crew, almost everyone had a shortwave radio.
There would be copper wire antennas strung everywhere above the camp, that we made from spent cap-wire used for setting off explosives placed down the shot-holes on the line.
The argument raged all winter as to which make and model of radio had the best receiver, with numerous trips made between the various Atco-shacks in camp, to listen to and rate the performance of the receiver of someone's short-wave radio.
By the number of Zenith Trans-Oceanic's in camp, it was agreed that their receivers rose to the top of the heap in performance.
Zenith short-wave radios were the most desirable at the time, and I always lusted after the Zenith Trans-Oceanic Royal D7000 (first brought out in 1969), but at the time the price of the D7000 was a 100.00 (in 1970 dollars) more than the CFC-5090.
When going head to head, the Zenith Trans-Oceanic Royal D7000 had slightly better selectivity and sensitivity on either end of the broadcast band than the Sony Earth-Orbiter CRF-5090, otherwise they were very close in performance on the shortwave bands.
The Sony Earth-Orbiter has several very nice visual tuning features, one being a red tuning light that illuminates when the received signal is at its strongest, and the second being a tuning meter that also indicates when the received signal is at its strongest.
I find the VFO tuning knob on the Sony somewhat easier to tune when listening to CW signals.
The Zenith Trans-Oceanic seen here is the H500 first produced in 1951. This particular radio is in very nice condition both in appearance and function, and includes the original manual, as well as the schematic and parts list for the radio, and the original short-wave list and map of the world that came with the radio when new.
If you are not familiar with the H500, the Wavemagnet antenna fastened in the lid may be removed from this position by removing the two brass knurled knobs visible in the photo, and with the ribbon cable and suction cups located and stored behind the rear cover, the wavemagnet antenna may be attached to a window for better reception.
When the back door is opened, the insides of the radio including the chassis are in wonderful condition, and appear almost as good as when the radio was new.
Although shortwave broadcasting stations are in short supply these days, I do enjoy listening to local broadcast station on the Trans-Oceanic as the sound produced by a tube radio is wonderful to say the least.
Of course the large speaker built in to the front panel helps as well.
On that note, I'll brew a cup of my favorite tea, and with the Zenith Trans-Oceanic murming softly in the background, I'll read a favorite book illuminated by the glow of my homemade blowtorch lamp.
Click on the photo for a closer look.....
