Search found 4574 matches

by Stevem
Wed May 01, 2024 9:34 pm
Forum: Technical Discussion
Topic: Can I use 6v6's in a 69 Super Reverb ?
Replies: 4
Views: 59

Re: Can I use 6v6's in a 69 Super Reverb ?

The only time I used 6V6 outputs at that high a voltage was in a Highwatt 50, and they where JJ brand since they are stated to be good up to 500 volts, and after having them in the high watt I do not question that.
by Stevem
Tue Apr 30, 2024 8:58 pm
Forum: Technical Discussion
Topic: Fender question
Replies: 10
Views: 234

Re: Fender question

All that has to be done is to remove a knob from the amp in question and compare.

This is front pot board and a chassis mounted pot for comparison.
by Stevem
Tue Apr 30, 2024 10:12 am
Forum: Technical Discussion
Topic: What should I build?!?
Replies: 7
Views: 184

Re: What should I build?!?

Silvertone 1484 with KT66 outputs.
by Stevem
Fri Apr 26, 2024 9:19 pm
Forum: Technical Discussion
Topic: Add an HT Fuse?
Replies: 9
Views: 295

Re: Add an HT Fuse?

Just to be 100% clear, my reasoning for what I posted is grounded in many decades of replacing power transformers in amps that have only a mains Fuse. In terms of a vintage amp that’s seen 40 plus years of use ( effects of heat accumulation) and the situation of repetitive blowing of the mains fuse ...
by Stevem
Fri Apr 26, 2024 7:51 pm
Forum: Technical Discussion
Topic: Add an HT Fuse?
Replies: 9
Views: 295

Re: Add an HT Fuse?

A HT fuss will cover the whole DC side of the amp, but you mainly have filters that can go bad and output tubes. Filters will give you notice before they go south enough to pop the main fuse, but output tubes do not when they short . In light of this I would be more inclined to place in line with th...
by Stevem
Fri Apr 26, 2024 10:19 am
Forum: Technical Discussion
Topic: Does anyone recognize this amp design?
Replies: 10
Views: 425

Re: Does anyone recognize this amp design?

The chassis I would say is not a one of since the nuts that will tie it up into the cabinet are tack welled in, so the amp started life as something else.
by Stevem
Thu Apr 25, 2024 10:07 am
Forum: Technical Discussion
Topic: Blackvibe 6L6 Strange behavior on tone pots
Replies: 17
Views: 558

Re: Blackvibe 6L6 Strange behavior on tone pots

If your looking for any mid boost with aFender type tonestack the only way to get any of that or even get a flat response out of it is to turn the volume way up, crank full up the middle and set the bass and treble very low.
by Stevem
Tue Apr 23, 2024 10:51 pm
Forum: Technical Discussion
Topic: Does anyone recognize this amp design?
Replies: 10
Views: 425

Re: Does anyone recognize this amp design?

Well it’s got very hard to find knobs from a Heathkit from what I can tell. It’s got a T03 cased transistor mounted near the fuses so I would have to assume it’s DC powered heaters. It looks like it’s got a old paper cased filter in there and 2 other filters that could be old and out of a Highwatt o...
by Stevem
Sun Apr 21, 2024 12:07 pm
Forum: Technical Discussion
Topic: '63 Selmer Treble n bass dilemma..
Replies: 4
Views: 199

Re: '63 Selmer Treble n bass dilemma..

I have used the jtm45 PT in a 65 Fender Bassman and one would be hard pressed to hear the difference with the slightly lesser B+ voltage.

If you can surmount the mechanical difference I say go for it, and you would likely save the owner 100 bucks in the end also.
by Stevem
Fri Apr 19, 2024 10:07 am
Forum: Marshall Discussion
Topic: Bad case of ghosting...I've tried everything.
Replies: 5
Views: 430

Re: Bad case of ghosting...I've tried everything.

You did not mention if you tried different known good preamp tubes.

I have had a condition like that a few times that was due to a preamp tube.

Have you tried a different speaker?
by Stevem
Fri Apr 19, 2024 10:01 am
Forum: Technical Discussion
Topic: Illinois brand capacitors still bad?
Replies: 12
Views: 458

Re: Illinois brand capacitors still bad?

Yes they are not at the bottom of the ladder any more.
by Stevem
Wed Apr 17, 2024 7:02 pm
Forum: Technical Discussion
Topic: Taming amp gain in single channel deluxe reverb build
Replies: 52
Views: 1287

Re: Taming amp gain in single channel deluxe reverb build

Note that 6BQ5 PP output stage needs 10 volts less of grid to grid drive signal then a 6V6 output stage does.
by Stevem
Wed Apr 17, 2024 3:34 pm
Forum: Technical Discussion
Topic: Taming amp gain in single channel deluxe reverb build
Replies: 52
Views: 1287

Re: Taming amp gain in single channel deluxe reverb build

Please clarifie what your doing better. You can't be pumping in millamps ( MA ) of signal like you posted, millvolts yes. Interms of the MV level are you saying .037 volts or .137 volts, I use about .115 volts. (-10 DB ) which is about a single coil pick up output level, if your pumping in .137 then...
by Stevem
Tue Apr 16, 2024 11:07 pm
Forum: Technical Discussion
Topic: Output Transformer formula?
Replies: 13
Views: 496

Re: Output Transformer formula?

Of special interest to you if you want to print them off would be pages 31 thru 38.
by Stevem
Tue Apr 16, 2024 3:32 pm
Forum: Technical Discussion
Topic: Output Transformer formula?
Replies: 13
Views: 496

Re: Output Transformer formula?

Note that it only covers tubes that RCA made and there's quite a few that only GE made that will not be covered in detail if at all in the RC30 book.