Silvertone 1484 diode substitutes

[waltk]

Hi,

I'm rebuilding my Silvertone twin twelve 1484. On the schematic, there are 4 1N3194, and 1 1N3754 diodes in the power supply section. I assume these are rectifying the power. I just want someone with more experience to confirm that I can just replace these with 1N4004 diodes. Anybody?

Also, it looks like somebody modded this already by replacing the output transformer (a good thing), and adding a few caps here and there. My plan is to leave the new output transformer there and "blueprint" everything else back to the original schematic. Anybody have any thoughts about this? Any mods that really should be there?

TIA - Walt

[lowbrow]

First, I am far from an expert...have been hanging out here and learning from those here who are. But, I just finished going through one of my two 1484's last weekend and will offer this:

It was recommended to me to use 1N4007 diodes instead....so far so good.

I replaced the OT transformer. It was stock and working, but I wanna gig this amp and need reliability. I went with the Webber replacement...$50 and more robust, but it retains the character of the original and offers both 4 and 8 ohm taps (a big plus to me). I just ordered another one moments ago for my second 1484 rebuild. Drop in fit, no mods necessary (except to drill a hole for a 8 ohm output jack).

I switched my standby switch to a Fender style....plan to do it again on my second one.

That's pretty much it...I found that both amps had some different cap values in the circuit, which where different yet again from the schematic. Coupling caps mostly...values seem to have increased from .01 to .022 then .047 µF. I went with .022 on my first rebuild and love the tone.

[waltk]

I replaced the OT transformer. It was stock and working, but I wanna gig this amp and need reliability. I went with the Webber replacement...$50 and more robust, but it retains the character of the original and offers both 4 and 8 ohm taps (a big plus to me). I just ordered another one moments ago for my second 1484 rebuild. Drop in fit, no mods necessary (except to drill a hole for a 8 ohm output jack).

Thanks for the quick reply! I'll go with the 1N4007 diodes you suggested. I bought this amp in the mid-70s, and have a vague recollection of the seller telling me that it was "modded" (I'm lucky to remember anything from the mid-70s). The output transformer was definitely part of the mods - it has 4, 8, and 16-ohm taps, and I was planning to drill a hole put in an 8-ohm jack as well.

That's pretty much it...I found that both amps had some different cap values in the circuit, which where different yet again from the schematic. Coupling caps mostly...values seem to have increased from .01 to .022 then .047 µF. I went with .022 on my first rebuild and love the tone.

I'm going to stick with the stock values for now. I have some great polystyrene .01 caps (dead-on value, super low ESR, and rated for 630V), so I'm using these everywhere the schematic calls for them.