Search found 620 matches

by maxkracht
Mon May 27, 2024 5:15 pm
Forum: Technical Discussion
Topic: Fender Brownface 6G7a question
Replies: 11
Views: 450

Re: Fender Brownface 6G7a question

Since the 5 triode version with the lfo buffer should have a slightly deeper tremolo, I would assume it would also have more tremolo on lower settings if everything is working correctly.
by maxkracht
Mon May 27, 2024 5:10 pm
Forum: Technical Discussion
Topic: Common anode mixer and Brown Fender trem operating points
Replies: 3
Views: 530

Re: Common anode mixer and Brown Fender trem operating points

really bizarre how the mixer tube could impact the trem speed in your revibe. I almost wonder if it's a speed of onset thing in terms of the phasing effect, i.e., an EQ difference that makes it seem faster? Yes, my money is on a perception thing opposed to reality. Was just jumpering in the resisto...
by maxkracht
Sat May 25, 2024 2:09 pm
Forum: Technical Discussion
Topic: Common anode mixer and Brown Fender trem operating points
Replies: 3
Views: 530

Re: Common anode mixer and Brown Fender trem operating points

- I'm struggling to get my head around the operating point of the splitter/mixer stage from the Brown harmonic tremolo circuit. If I re-conceptualize that stage's shared 4.7k/2uF shared cathode as a split cathode arrangement, I think it'd have 9.4k cathode resistance with a 1uF bypass capacitor. Th...
by maxkracht
Fri May 24, 2024 9:10 pm
Forum: Technical Discussion
Topic: Fender Brownface 6G7a question
Replies: 11
Views: 450

Re: Fender Brownface 6G7a question

It's also possible you got a pot with an odd taper. I've only messed with one original 6g7 and my revibe, so not a great sample size of harmonic trems, but both had noticeable tremolo on 1 or 2. Might be worth checking out Sluckey's revibe project if you are planning to build another. He has nicely ...
by maxkracht
Fri May 24, 2024 9:00 pm
Forum: Technical Discussion
Topic: Yet Another Two Stroke build
Replies: 30
Views: 1685

Re: Yet Another Two Stroke build

jer_vic wrote: Fri May 24, 2024 7:22 pm The layout for the Weber Maggie kit...shows resistors across the switch.
Yep, it's generally a good practice to add them when you are switching caps in and out. I like the input jack drawing on webers layout much better, and the 220k bleeder resistor on the first filter cap is also a good idea.
by maxkracht
Fri May 24, 2024 12:38 am
Forum: Technical Discussion
Topic: Yet Another Two Stroke build
Replies: 30
Views: 1685

Re: Yet Another Two Stroke build

Thanks. I think the voice/boost is that kind of thing. Here's the part of the circuit for that: Yep, my way only gives you one boosted setting but you get to keep the hi/lo input settings and get a footswitch option. If you add a pair of resistors across your switch it won't pop when you change set...
by maxkracht
Thu May 23, 2024 9:24 pm
Forum: Technical Discussion
Topic: Fender Brownface 6G7a question
Replies: 11
Views: 450

Re: Fender Brownface 6G7a question

I don't think it should be subtle early in the rotation. Might be worth subbing in a new tube like johnnyreece suggested or double checking your wiring if it bugs you.
by maxkracht
Thu May 23, 2024 9:00 pm
Forum: Technical Discussion
Topic: Series fuses and other oddities
Replies: 6
Views: 323

Re: Series fuses and other oddities

Thanks for the picture. I think it's one of these: https://www.piris.com/wp-content/upload ... sb-esb.pdf They're stated as both temperature and current protectors. I've not run into those before. Thanks for the link! I know how bimetallic strips work but didn't think of thermal protection. I guess...
by maxkracht
Thu May 23, 2024 8:46 pm
Forum: Technical Discussion
Topic: Yet Another Two Stroke build
Replies: 30
Views: 1685

Re: Yet Another Two Stroke build

Looks nice so far! Good on you for doing multiple test fits. For future builds, if you want to keep the two input jacks and have a hidden boost switch, here's a way to do it with an optional two button foot switch. https://ampgarage.com/forum/viewtopic.php?f=6&t=36383&p=454393&hilit=cloacal#p454393 ...
by maxkracht
Thu May 23, 2024 1:59 pm
Forum: Technical Discussion
Topic: Yet Another Two Stroke build
Replies: 30
Views: 1685

Re: Yet Another Two Stroke build

Any alcohol should do. Don't spill adult beverages on your shellac finish or you will have a bad time. I add a coat of paste wax for protection, lacquer then wax is even better.
by maxkracht
Thu May 23, 2024 2:59 am
Forum: Technical Discussion
Topic: Series fuses and other oddities
Replies: 6
Views: 323

Re: Series fuses and other oddities

xtian wrote: Thu May 23, 2024 1:54 am The Fender Bassman RI (tweed 4x10) has a 3A fuse (accessible outside chassis) followed by a 4A fuse in series, inside the chassis. Strangely, the 4A fuse had gone open when the client brought it in.
Weird, do you know if the client replaced the 3A?
by maxkracht
Thu May 23, 2024 2:57 am
Forum: Technical Discussion
Topic: Series fuses and other oddities
Replies: 6
Views: 323

Re: Series fuses and other oddities

Weird. Was this factory wiring? Bimetal strips are weird in an amp. I wonder if it's a thermal cutout for the whole amp when the inside air is too hot, just in a glass tube package. Glass tube is stock to the Musicman. I have worked on several, all have it. I'm speculating about bimetallic strip, b...
by maxkracht
Thu May 23, 2024 12:48 am
Forum: Technical Discussion
Topic: Strange pilot light experience
Replies: 8
Views: 413

Re: Strange pilot light experience

The amp could have an oscillation that is causing the power transformer to sag when you hit certain notes pulling down the filament, could also just be some oxidation on the bulb or a bad solder joint.
by maxkracht
Wed May 22, 2024 11:55 pm
Forum: Technical Discussion
Topic: Fender Brownface 6G7a question
Replies: 11
Views: 450

Re: Fender Brownface 6G7a question

The original was 10M. Weber sells them for the revibe, not sure if anyone else makes something better. https://www.tedweber.com/wp106ra/. Could also play with adding resistors to get a better usable range.
by maxkracht
Wed May 22, 2024 9:01 pm
Forum: Technical Discussion
Topic: Fender Brownface 6G7a question
Replies: 11
Views: 450

Re: Fender Brownface 6G7a question

Are you using a reverse audio pot for the intensity?