Search found 485 matches
- Thu Mar 21, 2024 3:48 pm
- Forum: Technical Discussion
- Topic: The Lost Art of Cable Lacing
- Replies: 16
- Views: 391
Re: The Lost Art of Cable Lacing
I've always been a fan too, but cable ties are so much easier, lol.
- Tue Mar 19, 2024 3:42 pm
- Forum: Technical Discussion
- Topic: ADA MP-1 schematic question
- Replies: 2
- Views: 78
Re: ADA MP-1 schematic question
Hard to say for sure without knowing what U7 and T3 are.
- Fri Mar 15, 2024 2:28 pm
- Forum: Technical Discussion
- Topic: Lowering B+ on Single ended amp with Choke input
- Replies: 9
- Views: 247
Re: Lowering B+ on Single ended amp with Choke input
This Hammond AO-63 amp does not have any cap before the choke. It also has a tube rectifier. I agree with the previous poster, the small value cap in the newer design is really only useful there to reduce HF noise. OTOH, as you get up to 1uF, you start to have a (really weak) cap input filter. I gu...
- Wed Mar 13, 2024 8:25 pm
- Forum: Technical Discussion
- Topic: F&T - Mersen
- Replies: 2
- Views: 162
Re: F&T - Mersen
If buy in sufficient quantity, F&T will brand the caps for you.
- Wed Mar 13, 2024 8:23 pm
- Forum: Technical Discussion
- Topic: Cap value
- Replies: 2
- Views: 117
Re: Cap value
To amplify a bit, 151 = 15 plus 1 zero = 150. Based on the type and size the 150 is in pF.
- Tue Mar 05, 2024 2:45 pm
- Forum: Technical Discussion
- Topic: PT reverse engineering problem
- Replies: 11
- Views: 314
Re: PT reverse engineering problem
Yeah, little high gain antennae.
- Tue Mar 05, 2024 12:23 am
- Forum: Technical Discussion
- Topic: PT reverse engineering problem
- Replies: 11
- Views: 314
Re: PT reverse engineering problem
I think R.G. is onto something. I put a 250 ohm 25w resistor across all three combinations, and read 3.2vac (again) on one, but the other two now read almost nothing (0.007xx vac). These three wires are the only "8 amp" (6 x EL34) sized wires coming out of the transformer, so they must be the heater...
- Sun Mar 03, 2024 2:36 am
- Forum: Technical Discussion
- Topic: PT reverse engineering problem
- Replies: 11
- Views: 314
Re: PT reverse engineering problem
There is very low resistance (< 1 ohm) between the three big wires.
- Sat Mar 02, 2024 11:12 pm
- Forum: Technical Discussion
- Topic: PT reverse engineering problem
- Replies: 11
- Views: 314
Re: PT reverse engineering problem
You'd have to ask Sound City.
The upper HT winding is ~250VAC and the lower is ~325VAC (both no load).
Here's the 'left hand' side of the schematic fwiw
The upper HT winding is ~250VAC and the lower is ~325VAC (both no load).
Here's the 'left hand' side of the schematic fwiw
- Sat Mar 02, 2024 9:57 pm
- Forum: Technical Discussion
- Topic: PT reverse engineering problem
- Replies: 11
- Views: 314
PT reverse engineering problem
I have a Partridge PT supposedly from a SC200, and the secondary windings and voltages it mostly check out as expected - but the three big wires (black, blue, green) coming out of the secondary, which one would assume are the heater winding, measure ~62VAC across two pairs and ~3.1VAC across the oth...
- Wed Feb 28, 2024 6:50 pm
- Forum: Technical Discussion
- Topic: Sturdy EL34s?
- Replies: 15
- Views: 386
Re: Sturdy EL34s?
Thanks for the suggestions
- Tue Feb 27, 2024 8:29 pm
- Forum: Technical Discussion
- Topic: Sturdy EL34s?
- Replies: 15
- Views: 386
Sturdy EL34s?
I have to re-tube a DR201 (6 x EL34, 650v B+). What are folks experience with current EL34 brands in a higher voltage situation (besides "boom!" )?
The 201 has a split supply, so the screen voltage is about 2/3 the plate voltage, which helps a bit.
The 201 has a split supply, so the screen voltage is about 2/3 the plate voltage, which helps a bit.
- Mon Feb 26, 2024 8:56 pm
- Forum: Technical Discussion
- Topic: Transformer rescue
- Replies: 6
- Views: 240
Re: Transformer rescue
All good information, thanks
- Thu Feb 22, 2024 5:02 pm
- Forum: Technical Discussion
- Topic: Transformer rescue
- Replies: 6
- Views: 240
Re: Transformer rescue
Thanks for the suggestions.
- Thu Feb 22, 2024 5:00 pm
- Forum: Technical Discussion
- Topic: What do you believe regarding the sound of passive components?
- Replies: 185
- Views: 4017
Re: What do you believe about the sound of passive components?
I think that in a controlled environment, using people with excellent hearing, you might detect some subtle differences. I would only trust double-blind tests, as humans are all too easily fooled (including themselves). I've caught myself thinking I heard a difference when adjusting the control on t...