TR full wave rectifier board in a Pro reverb ?

[Jazz-O-Sonor]

Hi,
Pls, can anyone describe the exact wire connections between a pro reverb PT and a twin reverb full wave rectifier board instead of the tube rectifier ?

My amp is a Pro Reverb style project w/ 2x10 Eminence Delta Demon speakers , deluxe style cab, Pro Reverb PT , Super Six Reverb OT, w/ 2&4 secondary taps(100v), 2x6L6, 5U4GB rectifier, 2x 100uF-350w in series and 3x 20uF-500v in parallel filter cap arrangiament.

The twin reverb full wave rectifier board comes from a late 70’ disassembled chassis.


Thank You , John

[JoeM]

What is the B+ voltage with the 5U4GB now in the amp? Putting in a SS diode FW from the Twin is going to increase this way up. Are you looking for more clean headroom?

[tubeswell]

Different SS and tube FW rectifiers explained

The Valve Wizard

Take a look at the TR schematic and layout. The TR is 3 diodes in series on each side of the HT winding, which then join at the reservoir cap. If you use 1N4007s, then the .01uF 1kV snubber caps are useful in eliminating diode switching noise (as explained in the above article).

As Joe says, going from a 5U4G to SS will raise your B+ by about 60V. You need to tie off and insulate the ends of the 5V winding. There shouldn't be any issue with filter cap voltage rating in a pro reverb (if it is a PR aa165?), but you should check the bias

[JoeM]

I did put SS diodes on a SFSR for a friend that used the amp for keyboards and wanted max clean. Tubes need to be rebiased, and you dont want cheap 6L6s, the plate voltage was somewhere near 500v IIRC. (The amp normally used a 5U4GB)

[Enzo]

I don't know if it is a good idea or a bad one, but the answer to your question is this. The two red wires that went to pins 4 and 6 of the rectifier tube would now go to the two anode ends of the semiconductor diodes. The cathode ends should be already wired together, and they go on to the amp circuits. The wire that would have gone to pin 2 or 8 of the rectifier tube now goes to those joined cathodes.

Cathode is the end of a diode with the line.

If your transformer has the 5v winding for a rectifier tube, and you are not using it, tape off the ends and secure them. In such situations myself, I like to solder the unused transformer wires to extra terminals on a terminal strip.

[Jazz-O-Sonor]

Thanks to you all for answering and 4 the great advices ,

thank you , John