On Thu, Jun 10, 2021 at 4:55 PM Greg D <ko6th.greg(a)gmail.com> wrote:
>
> Interesting find, Bob. I have a copy of the 1948 ARRL Handbook, and
> they have a design for a "Self-Contained 60-Watt Transmitter for Three
> Bands" (pg 173). Uses a 6V6GT and an 807 (not 804). Covers 3.5, 7, and
> 14 megacycle bands (crystal controlled or with an external VFO; CW
> only). 5R4GY for the rectifier, 1.2kv center tapped transformer. Yikes!
>
> Looks like quite a project. Speaking of 807s, I'm getting thirsty...
>
> 73,
>
> Greg KO6TH
>
>
> Robert Bruninga wrote:
>> I'm reading "the secret wireless war" and am surprised that the entire
>> basis for transmitters throughout the British traffic network including
>> spy radios and fixed stations transmission of decrypted ULTRA (Enigma)
>> traffic to those with need-to-know was handled by a two tube 6V6 and
>> 804 arrangement called the MKIII.
>>
>> The secret service built them all themselves from the design in the
>> ham radio handbook to avoid raising suspicions if they began buying
>> the few commercial ham equipment.
>>
>> That is the same arrangement as the first Novice transmitter I
>> built back in 1963 in middle school just 18 years after the war. Amazing.
>>
>> Bob, WB4APR.