Search found 498 matches

by renshen1957
Fri Nov 20, 2015 6:16 am
Forum: Technical Discussion
Topic: Perplexing 60 Hz hum - bad new can cap?
Replies: 31
Views: 4730

Re: Perplexing 60 Hz hum - bad new can cap?

I couldn't leave well enough alone. The can cap wasn't the solution. I put an original spec Dynakit 30-20-20-20 cap in it. It is probably just a rebranded CE but still not perfect. I swapped in a different choke to rule that out as well. If I pull the V1 preamp tube, the hum is not there, if that o...
by renshen1957
Sat Nov 14, 2015 11:11 pm
Forum: Technical Discussion
Topic: How Long?
Replies: 26
Views: 3297

Re: How Long?

I was using "New Math" from the 1960s. Drat that new math, only course I nearly failed. 7th grade was hell. The only thing I remember from it that had any use, Venn diagrams. Thanx hevvins they let me take Algebra I the next year, that stuff made sense. Nice to see you renshen! "Rarely seen but alw...
by renshen1957
Sat Nov 14, 2015 8:25 pm
Forum: Technical Discussion
Topic: How Long?
Replies: 26
Views: 3297

Re: How Long?

It depends on if your using comon core math or fuzzy math Hi, I was using "New Math" from the 1960s. One year 365.25 days X 24 hours=8,766 hours. 8766 hours X 125 years =1,095,750 hours. Which is the same as 1,100,000-4250. The difference in my answer is an error which is insignificant in electroni...
by renshen1957
Sat Nov 14, 2015 7:06 pm
Forum: Technical Discussion
Topic: How Long?
Replies: 26
Views: 3297

Re: How Long?

I was looking at some new electrolytic capacitor specs today and it seems that many high quality electrolytic capacitors have a life expectancy of 3,000 hours or 125 years or more. Does that shoot a hole into the 10 year life span theory of electrolytic capacitors in tube amps? I'm sure that heat a...
by renshen1957
Sat Nov 14, 2015 6:56 pm
Forum: Technical Discussion
Topic: Perplexing 60 Hz hum - bad new can cap?
Replies: 31
Views: 4730

Re: Perplexing 60 Hz hum - bad new can cap?

Hello all, I am restoring a beat up Sunn Solarus and while I have everything working again, I am chasing down a minor pesky hum. It is a 60Hz background hum, not very loud, that is not affected by the overall volume of the amp. I have a brand new can cap in it. If I place a parallel cap to the filt...
by renshen1957
Mon Nov 02, 2015 2:20 am
Forum: Garage Talk
Topic: Theft?
Replies: 29
Views: 4651

Re: Theft?

RWood wrote:I think Randall Smith's patent strategy is theft!
+1
by renshen1957
Mon Nov 02, 2015 2:15 am
Forum: Garage Talk
Topic: Theft?
Replies: 29
Views: 4651

Re: And Furthermore

Upon further consideration and also of the related posts: I believe anything older than 7 years is or should be in the public domain anyway. I know a patent can be extended for an additional 7 years but for sure that doesn't apply to nearly all the tube amp circuits out there now. As a point of law...
by renshen1957
Sun Nov 01, 2015 8:49 pm
Forum: Technical Discussion
Topic: Single Ended and Push Pull in One Amp
Replies: 5
Views: 1045

Re: Single Ended and Push Pull in One Amp

Has anybody built an amp that had both SE and PP output? I see BYOC has a kit called the Tweed Royal. Schematic below. Hi, The Kevin O'Conner "body control" will do SE, PP, and any degree in between. I built an amp after Kefin's Soma Amp in his book The Ultimate Tone Vol 5 in a Tweed Tremolux chass...
by renshen1957
Sun Nov 01, 2015 8:46 pm
Forum: Technical Discussion
Topic: Single Ended and Push Pull in One Amp
Replies: 5
Views: 1045

Re: Single Ended and Push Pull in One Amp

Has anybody built an amp that had both SE and PP output? I see BYOC has a kit called the Tweed Royal. Schematic below. Hi, The Kevin O'Conner "body control" will do SE, PP, and any degree in between. I built an amp after Kefin's Soma Amp in his book The Ultimate Tone Vol 5 in a Tweed Tremolux chass...
by renshen1957
Sat Oct 31, 2015 6:37 pm
Forum: Garage Talk
Topic: Theft?
Replies: 29
Views: 4651

Re: Theft?

Standing on the shoulders of giants just stipulates all proven things before you. Theft and a copy (or a clone) are two different things. Theft might be as simple as faking another person's work and claiming it's their's. It's a wide grey stripe. Theft starts at counterfeit and thereabouts... Hi, I...
by renshen1957
Sat Oct 31, 2015 4:21 pm
Forum: Garage Talk
Topic: Theft?
Replies: 29
Views: 4651

Re: Theft?

Messy boogers have special brand new tube technology! Mesa Engineering ripped off Soldano's SLO preamp to make the rectifier series, initially with the component values in the early models, and later with a few minor changes. Mesa isn't alone in ripping off the SLO circuit, Peavey 5150 also clones/...
by renshen1957
Tue Oct 27, 2015 8:06 pm
Forum: Dumble Discussion
Topic: KT66 in a 102 dumble style amplifier??
Replies: 6
Views: 2133

Re: KT66 in a 102 dumble style amplifier??

Oh well, it was just a thought. Glad you replied before i wasted my money. Hi, Several Russian KT66 have .9 amp heaters, there just big bottle 6L6GC tubes in KT bottles. Not the same thing, but give the appearance of different tubes. I like the sound of the KT66 tube (real ones) but might not be wh...
by renshen1957
Tue Oct 27, 2015 8:00 pm
Forum: Technical Discussion
Topic: Jim kelly single channel layout ?
Replies: 67
Views: 18831

Re: Jim kelly single channel layout ?

They help to reduce blocking distortion, kind of in lieu of a grid stopper. Normally you could use a diode and a zener back to back set so they come into play at around the tubes cut off input voltage say around 5v ish. In this case jim used it at around 1.2V to add a little diode clipping at highe...
by renshen1957
Tue Oct 27, 2015 7:53 pm
Forum: Technical Discussion
Topic: Jim kelly single channel layout ?
Replies: 67
Views: 18831

Re: Jim kelly single channel layout ?

According to Jim's schematic, the OT primary and the screens are supplied from B+1 (100uF filtering). There is a 2k 10W dropping resistor which drops the screen voltage by a mere 3V and is "shared" across all four power tubes. This is similar to Vox's approach where the OT and screens share the sam...
by renshen1957
Tue Oct 27, 2015 7:31 pm
Forum: Technical Discussion
Topic: Jim kelly single channel layout ?
Replies: 67
Views: 18831

Re: Jim kelly single channel layout ?

He claims to be getting 60 watts RMS from a quartet of 6V6's. I wonder how he's doing that. Hi, The how of 60 Watts from quartet of 6V6GTs (Sylvania in the schematic and Groove Tubes also mentioned in later literature) rated at 12 W was accomplished with an OT transformer of 4300 ohms, and voltages...