[R-390] Conversion of R-390 IF Deck

[Tom M.]

 Attached are two documents when pasted together yield the schematic for the R-725 IF deck.  I used this to guide me when doing my conversion. Note there is a B+ dropping resistor added in the R-725 IF deck

    On Monday, January 27, 2025 at 01:08:59 PM CST, Byron Tatum <bjtatum1 at att.net> wrote:  
 
 A quick question regarding the filament string re-wiring in R-390 IF deck to allow use in an R-390A. I am assuming 12AU7A tubes should be used (as marked on IF deck chassis) due to their slightly lower filament current draw. Are 5814A tubes to be avoided in regards to this string re-wiring?Byron W5FH    
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