Tube Amp Archive

Looks great! And, it would appear you found a larger OT, or is that just photo perspective? Sorry for the delayed response, haven't been logging in much lately. Thanks, the build came out well, and I quite like the sound of it. I'm almost finished building a Mojotone 5E3 kit I bought during their H...

13% off cabs and kit until Halloween.

https://www.mojotone.com/rocktober-tweed-deluxe?page=1

Victoria Amplifier makes clones:
https://victoriaamp.com/product/model-20112/

Or Clark Amplification:
http://www.clarkamplification.com/beaufort.html

Project wrap-up (warning, long(winded)). Recap: I built the 2nd edition of Dave Hunters Two-Stroke amp, basically a modified Princeton (5F2A) design. I started with a Weber 5F2A kit with no speaker (I had a Celestion Greenback) and sourced my own resistors and jacks, and changed a few other parts as...

I've fixed the crappy solder work on my problematic ground connection, and the hum has substantially reduced. With my crappy phone app., it measures 35dB at idle from 1 metre away. Background noise in the room (ie. with the amp off, and me standing still/holding my breath) is 30 dB. I'm calling it d...

Coming along! One thing to keep an eye on (I can't tell from the picture): You'll want to make sure the pilot light connections don't short to one another. Probably just an optical illusion, but the picture makes them look awfully close. Yeah, optical illusion. I twisted the rings for the 2 tabs so...

Update. So my hum is due to a shit soldering job I did on the 2 grounding wires I mentioned a few posts up. I suspected as much, so that was the 3rd thing I did, after checking if having no input cable made any difference (it did not) or if removing the pre-amp tube helped (hum stopped). Poking the ...

Ok, so switching the 2 output transformer primary leads did the trick. The amp worked after that. I was getting some fairly substantial hum, so I opened it back up and re-routed the wire from the cathode bias to pin 8 of the power tube - it was egregiously close to both the filament wires and the OT...

So the amp is done, now the debugging starts.... I followed Rob Robinette's startup procedures (with variac and lightbulb limiter), and everything went fine until near the end (step eight). Testing the amp with guitar and speaker (plugged into the lightbulb limiter) it emits a hum which builds to a ...

sluckey wrote: ↑Sun Jun 09, 2024 10:20 pm Can you post the entire layout diagram rather than just a snippet?

Here you go! FYI…. copyright Dave Hunter….

Due to company, etc., the project has been on hold for a few days. I've got it all wired up now, and have checked and double checked all my connections. IMG_4051.jpeg I'm almost ready for initial power up, but I have one more question. Can I join the two grounds (see attached diagram) together and s...

I'm looking at the two stroke layout, and the Weber Maggie layout, and they each have a slightly different wiring setup for the power/fuse/PT/switch. Is one design better than the other? The top one is the Maggie.

If you add a pair of resistors across your switch it won't pop when you change settings. Resistor value doesn't matter too much, too small and the caps will start to boost before being switched in, too large and it will take too long to charge the cap and stop the pop, I usually go somewhere around...

If you add a pair of resistors across your switch it won't pop when you change settings. Resistor value doesn't matter too much, too small and the caps will start to boost before being switched in, too large and it will take too long to charge the cap and stop the pop, I usually go somewhere around...

maxkracht wrote: ↑Fri May 24, 2024 12:38 am What is that pot doing?

That's the input jack. Not sure why they drew it exactly like they did the pots.