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After completing my second build of Dave Gillespie's Fisher SA-100 clone, I guess I was on a roll and was inspired to build again by another AK thread looking for a 'standard design' for tube amps. The thread mentioned the subject Cascade Tubes single-ended 6V6 amp. The amp is described by...

After enjoying my original build of Dave Gillespie’s outstanding SA-100 Clone EL-84-based power amplifier so much, I wanted to build a second version with a different aesthetic while maintaining the outstanding sound quality and overall performance of the original. I had already obtained a...

I’ve wanted to scratch build a pre-amp and have been searching for a schematic on-and-off for a while. I was looking for a good RIAA phono stage, tone controls, and an otherwise straight forward circuit using 12AX7 tubes. Neither a tape loop nor a loudness compensation circuit were considered...

I bought said TX-100 as a parts unit a while back. It was advertised as "parts only", but had a wood case and I ended up using part of the input selector switch to help resurrect my 400 CX-2 pre-amp. So it sat on the shelf, disassembled and looking forlorn, so one day between projects I...

I have really enjoyed my build of Dave Gillespie's SA-100 clone, built a while back and described here: https://audiokarma.org/forums/index.php?threads/building-fisher-sa-100-clone.861966/ I've been reading about the original recently and decided to obtain one for restoration and, perhaps...

Had to restring a late model (S/N 48xxx) 500C and could find no instructions that matched this unit in searches for 500C and 800C service literature. After studying it and fiddling around to get it strung, I checked some more and found that this unit more closely matched the dial mechanism for...

Hi, folks. I have been posting progress on restoration of a 'fixer upper' Fisher 500 that has gone reasonably well up to the testing phase of the power amplifier. All of the paper caps and electrolytic caps were replaced, including the cans, voltage and operational testing has been good to...

Hey, folks. I just wanted to post this for posterity in case it may be helpful to those of you trying to run down this occasional problem in the PAS pre-amps. I was restoring a PAS2 in nice condition but the unit had a low level but (too) audible 60 Hz hum in the right channel that preceded...

Recently obtained a 'project' 400-CX2 from an AK friend and close review showed that this unit is going to need a lot of work. Well, that's an understatement; this unit is basically a chassis that is going to have to be completely rebuilt. It's in pretty sad shape and there are a couple of...

Found this in the 5AR4 socket for a Scott amplifier. I can't even find a datasheet on it. Pretty beefy tube. No test settings in my B&K707 for it and tested weak as a 5AR4. Anyone have anything on it? Dave

Been doing some work on a 299A and have noticed on this amp (see pic) and others that each of the nested tone controls has a position called "Crossover". Can anyone help me with what this means? I can't recall an explanation in the manuals even though I've been through a few--perhaps I missed...

This X-200 was the first amplifier I got to restore for myself a couple years back. It was a fine choice and I still consider it one of my best sounding integrated amplifiers. I even bought a wood case for it and it looks fine in the listening room. I bought it in operating condition with...

The Scott 272 is their EL34 based integrated amp from the late 50's/early 60's. I got very interested in this beast of an amp when I restored one a little while back (thread on this forum) with the help of some good AK denizens. One came up on auction and I got it for not-unreasonable money...

Apparently Fisher FM-1000 tuners with dead meters are relatively common, according to what I read. There are two: a signal strength meter and an audio output VU meter. I have one now with a dead VU meter. On the (surely vain) hope that it was the internal copper oxide rectifier gone bad and...

Here's a kind of 'noodling' question that came to me while I was re-organizing my output tubes. I have a couple of nice NOS RCA 8BQ5 tubes on hand. The RCA data sheet says the 8 is identical to the 6 except for the filament voltage. These test very well at the design filament voltage, so I...

Hey folks, Last couple times I've powered up my restored 222B the amp (after it's typical lengthy warm up) started making noise, crackling in both speakers independent of the volume control. As a recently restored unit, I started checking around, thinking it might be the new rectifier going...

Working on a Scott 272 the owner purchased as "mostly restored, needing touch up." Rare, interesting, and quite complicated with EL34/6CA7 output tubes (KT77's installed) with massive iron and 35-40W RMS per side output. Some interesting features like the active "Dynaural Rumble Suppressor"...

Hey folks. Working on a Scott 272 (will start a thread shortly), but one immediate question as I work on restoring this beast. The original design uses 6CA7/EL34 output tubes. These are power pentodes with the suppressor grid coming to pin 1 and the cathode to pin 8. This amp is supplied...

After building my copy of Dave Gillespie's SA-100 EL-84/6BQ5 power amp clone, I decided I wanted a pre-amp to pair with it. I considered building from scratch, but was able to find a Scott LC-21 on ebay and decided to go that way after reading up on it and being an admirer of Scott gear as...

I found this neat-looking receiver (circa 1959) on the auction site the other day and really liked the look of it and bought it up to restore. Physical appearance was quite good and I am a bit of a sucker for "1950's modern" look gear, especially with Art Deco touches like you seen on the dial...

I got the itch to build again and, with than in mind, have been watching for something that caught my eye. Well, my eye found Dave Gillespie's threads on re-constituting the legendary Fisher SA-100 EL-84-based power amplifier with EFB (tm), so I took the plunge and acquired a pair of...

Hey, folks. I have done a lot of work on this receiver, including installing a bias/balance mod to individually balance the output tubes as well as un-/re-do-ing a lot of mischief done to it by previous owners. Finally got it working and sounding pretty well, but noticed a soft click in the...

I bought a pair of speakers from a fellow on BT and he threw in a 'partly working' 700T as a gift. I had not had any experience with early Fisher solid state gear, so was quite interested to pop the covers and see what it was all about, particularly the sound after restoring. This one was...

I'm working on a pair of neat old Bell 2200C amps for a fellow AKer, one of which is being a bit more of a challenge than the other. I've become acquainted with some of the differences between the 2200B model (for which a schematic is available) and the "C" model (for which no schematic is...

I am rehabbing another Fisher 400 and installing the usual mods (IBAM, screen grid resistors, 10 ohm cathode resistors, change from 330K to 200K grid resistors with 0.1 uF couplers). I'm also replacing the electrolytic caps, including both cans with axials under the chassis. The original...