[R-390] Help, Looking for Ballast Tube

[Roy Morgan]

Ballast Wanters,

The below mod is fine, but if you put the jumpers on the 12BH7 (and mark it 
well) then the radio is not changed at all.

Roy


At 11:41 AM 6/30/2004 -0700, KC8OPP Roger S. wrote:
>Here is the link and the text about the 3TF7 sub.
>
>http://www.r-390a.us/R-390A_Modifications.htm
>
>3TF7 Substitution Mod:  (optional, recommended)  Add
>jumpers on RT510 between pin 7 and pin 5, and between
>pin 2 and pin 4.  This allows you to later substitute
>a 12BH7A tube in place of your 3TF7 if (when) it ever
>fails.  (HSN issue 10, pages 1&2 or HSN reprints, page
>1)

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