The Amp Garage

gui_tarzan wrote: ↑Wed Aug 30, 2023 9:59 pm That's one ugly solder job. I did better when I was ten. Is that black wire what's holding the can cap in place???

Yup!

R.G. wrote: ↑Mon Aug 28, 2023 5:35 pm Thanks for the tip on the AC voltage.

Welcome.

Thank you for your interest in this amplifier and the info you have provided. This is first class stuff!

Ok, all went well. The two new 7-watt greenies look good in there. They still get fricking hot! The new 4x40u cap fit perfectly and provided ample space for wiring shenanigans. Quadrupled-checked my wiring... Powered up with a light bulb current limiter... No smoke! Good to go, as they say. Actually...

Yesterday I received the two NOS Sprague 40/40uF 500v multi caps, and I must say that the NOS smell of 44 year old aluminum e-caps is very nostalgic. But after all the professional guidance I received here at The Amp Garage, I’m not going to use them. Capacitance for each of the four caps was 46 to ...

… but you want new caps in there. … replace the electro caps. Of course, you’re both correct. My thinking is to make an attempt at forming, or reforming, the NOS caps. If they settle in at the proper parameters, and show no signs of excessive heat through the forming process, then they should be go...

xtian wrote: ↑Tue Aug 22, 2023 6:09 pm like dis:

IMG_2105 Large.jpeg

Those are some very cute kinks…

I appreciate all the good info here. Thanks to y'all again! At Mouser, I found some Vishay/Draloric 7 watt/200 ohm resistors that are only 3mm longer than those 5 watt cement resistors. Also found a vendor who seems to have a bunch of the original Sprague TVLU 2925 multi caps that Carvin used on the...

You can put a kink in the resistor leads or balance them on some heat shrink tube or something so there is some strain relief on the solder joint with the elevated components. Can anyone please direct me to what “kink in the resistor leads” or “heat shrink tube so there is strain relief” looks like?

This old 1980 to 1982 amp is not mine, but it is on my bench right now, and I noticed that this 47k/2w resistor on the schematic is actually 470k in the amp (red circle #1). The amp already was modified with a filter cap replacement that looks a bit ugly, and was wondering if the previous "tech" had...

Whether my assumptions and calculations are correct, You are calculating dc voltage drops. But none of those dc voltages even get to the send jack or V4B. Those dc voltages are blocked by C12 coupling cap. Thank you. Oblivious to the cap being there. Oblivious that this an AC signal pass. How does ...

The effects loop mod radically changes the gain at the grid of V4A, thereby changing the sound of the amp. Here is a design that doesn't change the gain. FX LP Dual CF 6.png Stumbled onto this thread while looking for more info on the SLO fx loop. Your schematic is very interesting, and I'm trying ...

Or possibly a dirty socket. Some tubes have bigger pins than others, could the JJ tubes possibly have smaller pins than what was in there for a long time, thus not making strong contact? Since the sockets for V2 and V3 were replaced last year, I just got thru replacing the V1 socket, yesterday. Sti...

The piggyback resistor is carbon comp. The rest are carbon film. Looks like Butler replace the diodes with FREDs. The shrink wrap is to protect the clumsy from the +/- 330Vac. I thought the shinny ones were modern production carbon comps... :oops: Don Butler is big advocate of using FRED's. I reall...

Here's an image after the Toneman got thru with it. I know for sure that the R riding piggy- back on the other R is a carbon comp. I have been assuming all the other shinny brown R's are carbon comps, too. Or are those carbon film? [IMG:1024:768]http://i443.photobucket.com/albums/qq157/greenie076/IM...

First post here! I’m electronically challenged, so bear with me… :oops: I have a 1982 JCM800 50 watt 2x12 combo (Model 4104), which was freshened-up by Don Butler, aka Toneman, over two years ago, with excellent results. Recently, I became interested in the numerous mods available on the internet, a...