Comments on: Multi-use vacuum-tube audio mixer circa 1960

By: Jesse

Jesse — Sun, 23 Jun 2024 01:19:29 +0000

I just happen to have a s-14, and a 0-1. I just may give this a try. I did a sweep on the s-14 with no load and it didn’t look so hot. Might just get replaced. What I should do is sell the s-14 and use those big bucks for more and better iron.lol
The tabs on the OT bottom in the picture do not match the s-14. So perhaps they did us a s-15. Odd as the circuit is single ended. Have you tried this yourself yet?

By: Doug jackson

Doug jackson — Mon, 17 Jun 2019 22:34:56 +0000

I’m trying to find schematics for a 60’s lang portable mixer and equilizer.

By: chris

chris — Tue, 28 Apr 2015 19:21:36 +0000

In reply to Chris. Hi chris. some of those 'universal' UTC O/Ps could handle DC on the primary. I don't know for sure which ones. but its risky. and their frequency response sucks anyways. if i was gonna build this, i'd use a utc A25. good luck. c.

By: Chris

Chris — Tue, 28 Apr 2015 18:01:07 +0000

Might the S-15 (12W PP) output transformer specified in this schematic be a typo? I would think that the correct UTC would be S-14 (single ended). If this is not a typo, I’m thinking of doing something similar to this with a UTC S-16 I have (30W PP) by running the DC through the whole 10K primary. What is your call on this? What might be the reason for specifying a S-15 instead of S-14?

Cheers