help with identification of estate sale finds

[ALBATROS1234]

just got back and i am assessing my buys.the first one has no name or writing on the chassis. it seems to be a stereo(one pt with 2 output transformers) seems to be each channel is a 7199, i assume the pentode portion of which is the input stage which feeds the triode within its own bottle as a pi driving 2 telefunken 7189 power tubes(industrial el-84).

[ALBATROS1234]

the second has a preamp with a gold faceplate shown below. an amp chassis that says amp-142. and a speaker baffle with a 15"(?) 12" and 2 small types maybe 4", the preamp has 1 12ax7 and the main amp seems mono with 4-6v6 ,2-5y3, and a 12ax7. i assume the 12ax7 is a pi with the 12ax7 on the small chassis with controls being the preamp. i suppose each 5y3 supplys 2 6v6s plus incidentals. i really would like to find schematics but a rudimentary search offers no hope with the magnavox amp-142. but i dont know where to even start with the noname brand stereo 7189 amp from post 1. any clues would be very hel[ful.

[sluckey]

Here's the magnavox amp-142 schematic. Unless you have more info on the preamp you'll probaby have to draw your own schematic. Same for the unknown amp.

[ALBATROS1234]

sluckey to the rescue again. thank you sir. yea i was just throwing a hail mary that maybe someone would look at the pics and have some info for a starting point. more research indicates there were a few different "142" types aa,bb, etc. there is of course a smearedish letter maybe a single "C" but not sure. its a bit strange at least to what i am used to .

the power transformer is working on the magnavox and the 4 6v6 and 2 5y3 as well as 2 12ax7s all work. speakers work i will try to trace it down with some pencil and paper with my rca manual to see what is different in my version from a general schematic.

the 7189 tubes all work and i can trace it down too just was hoping a keen eye would say "oh yea i got one of those at a garage sale...they are amazing ...here are all the documents there are on it in this attachment" lol just kidding but it would be cool if it could be recognized by someone. thank you guys for any future commetary.

[sluckey]

That schematic is part of a Sam's Photofact package. The rest of the Photofact and several pics that look just like your pic are available at...

     https://www.radiomuseum.org/r/magnavox_amp_142.html

This is a nice power amp just as is. All you need is an external guitar friendly preamp to plug in and start jamming. You probably already have a guitar amp, just needs a preamp out jack.

[ALBATROS1234]

thats what i was thinking as i came up to the table which had both these amps plus, a huge hallicrafters s-40 tranceiver, a magnavox shortwave and a shoe box with 50 loose tubes rolling around.got a dozen tubes including a couple 6sn7s(philco,tung sol), 6aq5s, and various other useful tubes. i american pickersed them down to $120 on the magnavox and $50 on the one with 4 telefunken 7189s. may go back tommorrow and low ball them on the hallicrafters they want $50 on and oddly want $175 on the caseless magnavox shortwave. worst case parts etc.

[DummyLoad]

nice score.

on the stereo amp, the 7199 on the left is gassed out.

IIRC, the quad 6V6 magnavox amp is a 30W mono amp.

--pete

[PRR]

> the first one has no name or writing on the chassis.

It looks like kin of a Fisher I once had. Even the snap-in pots. Mine was a bit smaller, laid out different, and had a vacuum rectifier, and golden cage. This may be similar iron but built to hide inside a console. See if that helps find a match. 2X24W rating. A beefy "18 Watt", twice.

My yardsale score today was a drywall screw-gun in good working order with repairable cord. (I'm fixing a house so this IS a score.)

[PRR]

My Fisher was a SA-100 (tho possibly a prototype.... I got it oddly):

https://www.hifiengine.com/manual_library/fisher/sa-100.shtml

Your tube lineup has a pentode gain-stage but will otherwise be more similar than different.

Somewhere was a site with "every" Fisher from before Avery sold-out, all those luscious consoles etc. I'm not finding it.

[John]

While looking for that website, I stumbled across this, in case anyone wants a read...


https://www.rollingstone.com/music/music-features/a-conversation-with-avery-fisher-56745/

[John]

Hey, maybe this one is it?


http://www.hifimuseum.de/fisher-handbook-1968-2.html

[ALBATROS1234]

thanks so much for the replies.

@dummyload , yeah i saw the telltale milky getter flash. on the realistic 7199 . was mainly excited about the iron and 4x7189

@prr yes that does look quite similar. fisher gives me a good starting point. it has an odd(to me) rectifier with these pointy diodes(silicon maybe germanium?) with 3 trimpots maybe voltage regulator?

[ALBATROS1234]

thank you john will check those out.

 this must have been i a console as on the front is a small slider type switch only and the back has the snap in level pots for each channel as the only control i assume as a set and forget master volume and the receiver i assume would have the main volume ,tone and power switch at the least maybe even a radio?

[sluckey]

We called those pointy diodes bullets. They are silicon. The 3 aluminum cans are the filter caps. This is a stereo power amp. Tone controls will be on a separate chassis.

[ALBATROS1234]

i also got this rca in the grab bag tubes. it looked like a dual triode so i got it,all the grab bags were $1. i plugged it in one of my amps in place of a 6SL7 and it worked and sounded like slightly less gain. the 6SL7s i have have heartier plates. could this be a 6SN7?

[ALBATROS1234]

i sooooo wish the tube manufacturers would have made a more durable ink/paint for marking tubes or else marked on the base because i have many tube where i can barely make out what they are and had to use a paint marker to write on them for fear it would rub off and/or i would forget. i just got a 1947 motorola 67f11 recordplayer/radio and the tubes were so crusty i couldnt read them i tryed to carefully wipe off with damp cloth but all the ink washed right off. of course i did them one at a time and there was no fear as there was a label stating tube types had them. but still what if its like the tube above which has nothing on it. i used deductive reasoning to figure out it was a dual triode but normal people would just been screwed back then. you would think they knew this was a problem and remedy the situation over the many decades .

[ALBATROS1234]

it seems it is one of these the plates look identical. so i guess $1 was a good deal

https://www.ebay.com/itm/RCA-6SN7-GTB-PLATINUM-MATCHED-QUAD-SILVER-PRINT-well-balanced-in-Gm-Ip-/142414102161