What’s on *YOUR* workbench?

waywardmatt said:
getting the twin on the bench for a tune up and new caps.View attachment 74837View attachment 74838View attachment 74839View attachment 74840
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Fortunately, those “blue bomber” coupling caps are likely still good. Rarely have I seen them bad.
The cardboard Mallory’s were probably ready to say goodbye a couple decades ago (I mean, who would think cardboard is a good container for long term liquid storage).
The only surprising thing (and I’ve always changed as a cap job), those white Mallory’s everywhere are prone to being good one day, dead short the next— what surprised me the most is that apparently there was a service bulletin and voluntary recall on them in the late 70s/early 80s because of this behavior (we are talking caps doing this that are well within the 15yr expected life… and tested good prior to the failure). Apparently a few hifi mfrs had enough warranty claims on these caps shorting and taking out whole output sections in high end equipment! And Fender had them in their bias supplies, yet never took part in the recalls!

If you get a chance, check the carbon comp plate resistors. Typically they are known to get noisy and drift high, but in my experience (and it may be related to age), but the late 70s Fenders don’t seem to show this as bad as older models. (Personally, I just replace as I don’t want an amp being a boomerang and coming back to me prematurely… but there are folks who have a hard on for it looking “all original”, so there may be a case where newer production carbon comp resistors may be a way to keep them happy. I just don’t have enough data either way to have a warm fuzzy about it
 
The motherlode of germanium transistors (and diodes) landed on my workbench this week.
...with hFE and DC leakage measurements... very helpful since I don't have a DCA

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These were a gift from @jwin615.
You guys are incredibly generous around here.
(Somehow, both PIF boxes and these transistors arrived with 1 week's time.)
Something terrible is going to beset me now, right?

Most interesting part? The first silicon transistor out of Silicon Valley, the Fairchild 2N697, which led me to read all about the traitorous 8.

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OK, now I have to get building, and get PIFing...
 

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Locrian99 said:
The jc-120…


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Having a hard time finding exactly where it begins. Making a slightly better than stab in the darn and replaced c47 and c53
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Hmm with that noise? bad tube/dirty tube sockets? Crap…no tubes.
old carbon comp resistors? Nope, not there either.

all joking aside, can you isolate it to preamp/power amp/channel etc?
that said, it looks like an 80s model by the looks of things. Perhaps an electrolytic is starting to dry out?
 
Giorfida said:
Hmm with that noise? bad tube/dirty tube sockets? Crap…no tubes.
old carbon comp resistors? Nope, not there either.

all joking aside, can you isolate it to preamp/power amp/channel etc?
that said, it looks like an 80s model by the looks of things. Perhaps an electrolytic is starting to dry out?
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What he said. I'd also pull tubes one by one. Maybe even a recap. Although, they don't look that old.
 
Gordo said:
Shot in the dark but try a cable between fx send and return in case the jacks are getting oxidized and noisy.
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jwin615 said:
Ain't not no toobs in der is it?
All Japanesee cran-zistors.
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So i didnt really mention what i do know already about it. Its from channel two. The video shows a couple solid hints on where it is coming from. So its in channel two, but not affected by volume. So logically its after the volume control. When switched to chorus it disappears, so it must be after the signal goes into the chorus section as well. Also which i didnt mention. Its somewhat intermittent, but it seems to occur when the amp has “warmed” up. Also there is crackle on pots even after they have been cleaned with deoxit, sign of ac getting in from a leaky cap i believe. These clues led me replace the two caps i did. Ill see tomorrow if it fixes kt…
 
Giorfida said:
Hmm with that noise? bad tube/dirty tube sockets? Crap…no tubes.
old carbon comp resistors? Nope, not there either.

all joking aside, can you isolate it to preamp/power amp/channel etc?
that said, it looks like an 80s model by the looks of things. Perhaps an electrolytic is starting to dry out?
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Well so yes got it isolated to the pre amp after the volume control. First thought was c53 which i changed out a few days back. Turns out it was a bad film cap. No more noisey noise only the sweet sounds of 80’s roland chorus glory.

I’ll probably flip it got it cheap cause it made that noise it just takes up too much room in my small space. But man the thing sounds glorious :)
 
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Got this pedal (PPCB Soldat) in the cheap lot of a bunch of DIY pedals, most were working, some needed fixing up (already fixed up the Abductor II and the Electric Mistress) and a couple had no footswitches. I think the original owner used those with a loop switching system where they were always on, so no need for a footswitch.

But I would personally prefer one, so I'll see how to rig up one here. I think I can maybe fit in one of the relay switching boards from szukalski and fit in a SPST switch riiiight near the bottom (and since it will have velcro on the bottom, the footswitch being off center shouldn't be an issue). I'll obviously have to re-do the wires, but all in all not a big task and I probably will be able to keep the enclosure.

On the flip side, I think the owner painted the enclosure themselves but didn't use any kind of clear coat or anything. Any time I handle the pedal I get small paint flakes in my hands and have to wash them. So the first order of business is taking the pedal out of the enclosure (thankfully the power jack is an outie so no need to desolder to remove - might have to desolder some wires for the LED though) and clear coating it.

Or actually I think the first order of business is checking that it works before I start messing around with it.

Edit: Well, it works, I'm not 100% sure if it works correctly, need to check some SDT-2 demos. It doesn't play well with the Clandestine Preamp at all, gets way too muddy. It also seems quite muddy in general, I found turning the gain up leads to a lot of mud very quickly. Also quite bass heavy, even with my cheapo Tele knockoff with single coils. Output at noon is definitely lower than what demos are showing me. Blah, I think I need to check the resistors, volume pot at least is correct. Resistors seem fine, I'll try a different op amp later.
 
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Band of Dans said:
There's something disturbing about that giant bright red LED bursting up out of the flesh-colored enclosure 🤢
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It's actually more coppery in real life than any flesh-color I've seen, but I see your point.

I do wonder, if you're going to paint something so badly that it will constantly flake when you touch it, why paint it in that color?

I added the clear coat so it should be fine now when it dries up, but still. If it wasn't a huge pain to strip and repaint (or just strip it and leave it natural) I would do that instead.
 
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