Looks a lot like my Ameco 2M converter and my parks 432 converter both use nuvisters.
Both pretty decent.? The nuvistors wanted .135A per tube or .675 amps at 6.3V (4.2525W).
The dynamotor was aybe 65% efficient in providing the 90-120V needed.
I have a HE45A 6M am TRX,? uses 2E26 final.? Used Vibrator supply and all tube.? Sucks down
about 4.5a on receive run the heaters and upward of 6A on TX.? IT does about 12W.
Most were run off 120V AC.
Back in the dark ages (1970) I used to service radios like Motorola TU44UHF
For 4watts on UHF FM the standard power harness used 00guage wire direct to the
battery.? Running the RX alone could kill the average car battery is less than 2 hours
without the engine running.
Tubes are cool but for portable their power needs are painful.
Example A TBY-8 a 28 to 80mhz wwii? backpack portable using 7 tubea two for the audio,
one for crystal calibrator,?and Acorn tubes for superregen RX (two tubes) and two for TX.
33 pounds complete in the pack.? About 18 pounds of that was batteries.? The 0.5W TX had
a useful range of 10,000 yards.? ?I have one!, they were also known as codetalker radios.
I have a three tube (1R5, and two 1u4) 80m rx, it needs 1.4V at 150ma (tube heaters)
and 90V at 7ma for the whole plate load.? Ok for Am, forget SSB, too wide for CW.
Generally heating the tubes was hungry for power and the high volts were short lived.
The idea of a valve final for QRP assumes you car is the power source or
other large battery.? As heating the tube and providing the high volts will eat
many watts for maybe 15-25% efficiency (battery to RF).
Acorn tube were cool but Nuvisters were way better and smaller.
--
Allison
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