[R-390] Ballast Tube, 3TF7

[Roy Morgan]

At 10:12 PM 12/17/2007, you wrote:
>The Ballast Tube in my R-390A just went bad. My usual source for tubes 
>wants $30.00 for one 3TF7. Is this about the going rate? If not, I would 
>appreciate reccomendations for an alternate supplier.

Harold,

Put the old tube in a little stand and put it on display. Do not buy a new 
one.  Use a 47 ohm 10 watt resistor instead. (or whatever the right value 
is!)  Do not make a highly engineered solid state computer controlled 
regulator substitute module.

Or: get a 12BH7, jumper a couple of the pins and plug it in.

OR put 12BA6's in the PTO and oscillator sockets, jumper either the ballast 
tube itself or the socket...

Then use your radio. Spent the $30 on other spare tubes.

Roy




- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing
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