WINDSOR, Conn. — It’s obvious to many readers of Radio today that a large fraction (sometime it seems like all) of the broadcast engineers out there are also hams — and many have blurred the lines between vocation and avocation by restoring old AM transmitters for ham use.
Now even the ARRL is getting in to the game, thanks to a joint effort with the Vintage Radio and Communications Museum of Connecticut. They’ve taken a classic Gates BC-1T AM broadcast transmitter and given it a second life on the ham bands for occasional use under W1AW or under the ARRL Headquarters Operators Club call sign, W1INF, according to the ARRL news. The transmitter will be located in the ARRL Lab.
Led by broadcast engineer Dan Thomas, NC1J, VRCMCT volunteers restored the1 KW transmitter to operating condition after obtaining it from the National Capital Radio and Television Museum in Bowie, Md. The VRCMCT will retain ownership of the transmitter, while the League houses and maintains it on loan.
“While a shift from the higher end of the Standard Broadcast Band to 160 meters alone might seem rudimentary, various stipulations added a level of complexity,” according to the same article. “First, the transmitter had to be modified as little as possible, retaining original components. That ruled out completely redesigning the circuitry. The 833 final amplifier tubes, better suited for broadcast-band use, would be retained as would the inductance-heavy tuning circuits.”
Another requirement called for the transmitter to function on 75 as well as on 160 meters. ARRL turned to AM guru and veteran broadcast engineer Tim “Timtron” Smith, WA1HLR, of Skowhegan, Maine, to handle shifting the BC-1T from 1340 kHz to the ham bands.
“Timtron not only has been an AM mainstay on 75 and 40 meters over the years, he’s engineered all manner of AM, FM, and HF broadcast transmitters in his extensive career. This combination of familiarity and experience made him a logical choice to handle the conversion to amateur use of the Gates BC-1T.” This particular transmitter lived its first life transmitting country music from KPGE in Page, Arizona.
The modified transmitter was tested at the 250 W level on Feb. 22 and the modifications were found to be successful. Eventually, visitors to ARRL headquarters will be able to see the transmitter on the air and possibly use it, by advance request.
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