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Re: Vacuum-tube final for QRP transmitters?

 

The 2E26 Allison mentioned is perfect for portable rigs as they were designed for VHF mobile radios (think vibrations and the like). AF4K(SK) used one in a transmitter design that worked fairly well.....unfortunately, I don't have a schematic of Bry's rig. I think he used a 6C4 or similar for the oscillator.?

Lee KX4TT



On Saturday, September 16, 2023 at 12:36:23 PM EDT, Jim Strohm <jim.strohm@...> wrote:


Remember the 12BY7. ?


73
Jim N6OTQ


On Sat, Sep 16, 2023 at 11:26?AM Mike Downing KC0Y <michael.downing.kc0y@...> wrote:

Heathkit used the 6CL6 as a linear driver in the HW101 and similar SB series line. Mike, KC0Y

On 9/16/23 11:21 AM, ajparent1/kb1gmx wrote:
Nuvisters are for receiving use and max power would be in the 2-3W range for the tetrodes.
The triodes do less and must be neutralized or they will oscillate like most triodes

I happen to have worked with them and as tubes go they wer excellent to about 700-800mhz
but not so much for RF power.

Most of the tubes that would do any power over about 3W are costly for power consumed
(heater/Filament and plate).

FY look up the Hallicrafters HT37 phasing transmitter....? big and heavy and required much
tuning to keep them clean as the tubes drifted with age.? I know, I have one that I fire up?
from time to time.? There are others of the era.?


--
Allison
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