Thanks for this video. I would've liked to see better where the soldered wires went into the loom. They kinda dissappeared. Also- it would've been helpful to see where you connect the meter. Thanks again. Just bought a used twin that I'm refusing to take back and I hope this is my issue.
Its rather sad that the manufacturers are cheaping out on the builds. Watching Lyle and uncle Doug plus the Australian contingent your hopes would be a realisation that they really should change their standards. Thank god there are clever bods such as yourself willing and able to bail us out ,regards
Great to see this in detail Brad, A lot of what you mentioned lines up with what I've heard of modern reissues, but I guess that's the compromise I bought into! Will definitely swing by again
It’s amazing how many corners get cut on modern amps. Obviously, old amps suffered the same but at least they’re easier to work on. I’ve been so lucky with my amps.
Got to love a good J solder joint. As an apprentice we had our work kicked back when making up wire ends if we twisted the wire before terminating. 😡 It alter the cross-sectional area of the wire bla bla bla. It still has the same amount of copper but oooh no. Catch you next time (if big clives not live that is 🤣) nice one 2x👍
Hey Brad, I have a 1991 blackface twin reverb with an almost identical issue except that it's burning the other side of the fuse holder (and eventually blowing the fuse). I suspect there is something going on downstream - maybe a short in one of the power tubes - so the fix you've implemented here would probably not be advisable in my case. Would you agree?
You probably just had a slightly higher contact resistance on the other side of the fuse, but it's likely the same issue. I'd suggest getting a tech to check it out if you're not comfortably confident that there's no other problem, though.
If it's bad to run an amp with no speaker why is it ok to run it with no springs attached even tho' the reverb driver circuit is basically another power amp?
Because it's tiny and isn't capable of generating flyback voltages that would cause problems. It's never been an issue for me or any of my fellow techs, but if it bothered you, you could make a dummy load out of an RCA plug and a 5w resistor.
Just to play devils advocate here; but doesn’t what you’ve done here leave the (very expensive) PT open to being destroyed in the event of a downstream problem - like the shorting of a tube heater for instance?
Like every Fender, Marshall, Vox amp up to the early 90's? Like every Mesa Boogie ever made? Providing a suitable mains fuse is used, it will open in the event of a heater short. If an unsuitable mains fuse is used, in most cases, all bets are off.
