FW: [AMRadio] FW: next project!

[Jim Isbell]

Well, I dont think they will do as well as the pair of 4D32s for power, 
but they would really look great.  I am considering a pair of  4-125As 
modulated by a single 866 for my next project.

Brett Gazdzinski wrote:

>Interesting idea!
>I have some 4-125 tubes, however, they like higher voltages,
>which means bigger parts like chokes, plate tuning caps, insulators,
>etc.
>You can get 300 watts out of a 4-125 at 2500 volts with
>plate modulation.
>How would you modulate a 4-125 with one 4-125?
>
>In anything other than plate modulation, you will have the high voltage,
>but low efficiency and likely under 150 watts out, under what a pair
>of 4D32 tubes at 700 volts would do....
>
>Brett
>N2DTS
>
> 
>  
>
>>How about a pair of 4-125A's using one as modulator the other 
>>as final 
>>and use a microwave oven transformer for plate power, keep 
>>everything in 
>>one case.
>>
>>Brett Gazdzinski wrote:
>>
>>    
>>
>>>What would you build/want as a 40 meter hi fi AM transceiver?
>>>I want to limit the power to the 200 watt and under class, but
>>>can put the high voltage power supply in a separate cabinet/rack, and
>>>sit the transceiver on the operating desk, to save space and weight,
>>>or, run one 4d32 at 100 watts with everything inside one box.
>>>With a separate power supply, I could likely go to 200 watts
>>>out of 2 4D32 tubes, or something different?
>>>
>>>It can be simple, frequency select switch, rf gain, S meter, mic
>>>gain, plate tune and load, rit,xit?, bass and treble audio EQ.
>>>I will likely put many meters on it, for grid drive, plate voltage,
>>>mod current, negative cycle loading , etc., can be a multi meter, or
>>>separate meters (I like meters).
>>>
>>>Or I could build a regular receiver with regular tuning, and 
>>>      
>>>
>>leave the
>>    
>>
>>>trans xtal controlled, digital display receive frequency readout.
>>>
>>>I can include 2 bandwidth choices, say 5.5 and 4 KHz on the 
>>>      
>>>
>>receive filters.
>>    
>>
>>>What would YOU want in a 40 meter transceiver for AM?
>>>
>>>Brett
>>>N2DTS
>>>
>>>      
>>>
>
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