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Blown power transformer in Denon DRA-345R Tuner Amplifier_part 2

Trevor Taylor

Jan 25, 2017
Jan 25, 2017
Just a heads up to an archived Thread on someone who requested the secondary voltages on a Denon Receiver Amp DRA 345R.
I own two of these amps presently, one since new, purchased early 90's, still runs and sounds great.
A very good sounding quality amp in my view.

Recently purchased a second one hoping to repair.
Found that the primary of the power transformer is open circuit. Seems there's no way of finding the thermal fuse on the outer of the tranny, must be buried deep.

In response to someone earlier who also had a blown tranny for the DRA-345R and wanted to know the voltages on the secondaries for adding a suitable replacement transformer.

The 2 red wires of the secondaries are centre tapped with a black wire all go to the pcb
voltage one red to other red = 65.3 VAC. Each Red to centre Black = 32.8 VAC

Voltage on the 2 Blue secondary wires = 4.2 VAC

Voltage on the 2 Orange secondary wires = 16.8 VAC

I have an older Denon Receiver, that runs a bit ratty, so am looking to rob the tranny from that and install in my broken DRA-345R.
Only challenge is that the older Denon doesn't have the two orange secondaries, it has the reds and the blues, of very similar required voltages, just doesn't have the orange secondaries,
If anyone knows the current draw required for the orange secondaries on the DRA 345R and any ideas how I might tapp into the power supply somewhere for the extra 16.8 VAC out. then all suggestions recommendations greatly appreciated.

Was thinking maybe a second smaller transformer or possibly a voltage drop down converter added to the red secondaries, hoping something along these lines might be operable.