Converting Hammond AO-29 to Princeton or Deluxe Reverb clone

[chopstuck]

I have a few of these long 6v6 chassis and was considering a mutant Princeton with it's nice tube trem and a DR PI. There was a discussion a while back that noted the big PT had quite a bit of internal resistance and had limited current reserves. Would that AO-29 PT, OT and chassis be suitable for a Princeton Reverb or a one channel Deluxe Reverb ?

[Structo]

Yeah I converted one.

It started out to be a 5E3 Deluxe but as I went along I didn't care much for that so it morphed into more of a plexi design.

I only used one preamp tube, a PI and the 6V6's. I kept the 5U4GB recto tube since it drops 44v.

The biggest issue was the HT voltage because without a load it was hovering at 460v!

I used a 50 watt 125v Zener on the center tap to bring down the voltage to a manageable level.

Skyboltone helped me quite a bit when I was starting out on it.

At first I had planned on trying to use most of what was in the chassis but after a couple hours of trying to salvage stuff and keeping the layout, I got frustrated and gutted it all except the recto socket.

I shortened the chassis by around four inches as well.

It went from this:

[IMG:800:600]http://i23.photobucket.com/albums/b392/ ... G_0304.jpg[/img]

To this:

[IMG:800:600]http://i23.photobucket.com/albums/b392/ ... G_0092.jpg[/img]

[IMG:800:600]http://i23.photobucket.com/albums/b392/ ... G_0035.jpg[/img]

I've since replaced the orange drops with Mallory 150's.

It's a pretty cool sounding amp and has that plexi sizzle.

I also wanted to add that if yours has the 5U4GB recto tube, that it drops around 44v but has a pretty big current draw at 3 amps.

If you can reduce the voltage another way you could go with a lower current recto tube and that should free up enough current for a couple more preamp tubes if you wish.

Here is some recto info:
http://acruhl.freeshell.org/mga/main/rectifiers.html

[chopstuck]

Looks like you didn't use much of the original components. I too have tried to save the components but I can't justify the wasted time vs. the $35 tops in caps and resistors. Most of them aren't anywhere close to the values I need and I'm running out of empty coffee cans to store them noxious chemical devices. Hell, I used to save wire longer than 3 inches too.
I thought by running a larger group (stock amount) of preamp tubes I would load down the HT low enough like in the original design. I might even be crazy enough to use some of those single triodes. Call me crazy.....

Any thoughts ? Not about the crazy....

[Structo]

If your amp is like mine, it had a lot of 6v tubes.

I think I salvaged two 12au7 and one 12ax7. All Sylvania's.

The treasure was the silver topped Sylvania 6V6GT's and the RCA 5U4GB tubes.

Skyboltone seems to know these amps pretty good and he said that the PT is on the soft side and can't supply a lot of current.

But since the 5U4 draws 3 amps perhaps you could change that to something that draws less freeing up some current for more tubes.

Be sure to check your 6.3v heater voltage as well as the 5v taps for proper readings.

[tweedeluxe]

Structo - did yours originally use a field coil speaker?

[Structo]

Structo - did yours originally use a field coil speaker?

Yes it did but I was told that the output transformer would power a modern speaker but I didn't use it since I had an extra 50 watt OT on hand.