Dumpster Recovered Gibson EH-150 Help/Guidance

[Reli-Teli]

Wow! It looks like I came to the right place. I was reading up on a few threads before posting mine, but now I have a better Idea of where to start. I got a Vintage RCA CV5 in the mail today, I'm itching to get this thing going correctly and hear what its made of. I never looked inside of an amp before I got this one so I have ALOT to learn. I will be doing as much of the work as I can, I'm stubborn that way. I've been looking all over for the right Schematic. According to my tube sockets it calls for a 5Z3, 2x 6L6, 3x 6C5, and a 6F5. But the 2 schems that I keep running into call for different variations of the two. The Serial reads 7824. If someone could point me to the right schem I can get to work trying to find where all this stuff is you guys are talking about (Noob) If anyone wants to dumb it up for me feel free. The only altering I've noticed is an extra speaker out right under the fuse holder, the yellow caps, a couple wires, and the external transformer has mix matched mounting hardware so it may have been serviced once. I'm very fortunate that I have Moyers Electronics to turn to for parts and vast amounts of knowledge. It's like a time machine walking into that shop. Bill offered to test my tubes for me to see what I might need. He found some NOS metal military grade 6C5s for $5 each and, Vintage 6L6 tubes for $13 each, I didn't even ask about a 6C5 yet he had to dig deep to find the other ones. And if all else fails I have my friend who works as an engineer at a local university. That's where I get some help with my pedals. They recently got machines to make Circuit Boards! All the wiring is still supple and isn't brittle, just some mildew. The 12" speaker as Absolutely perfect, with no signs of damage on any of the components and sounds amazing. I came across a success story where someone removed paint from tweed using 3M Safest Stripper. I want to try that first then recovering if that doesn't work. I never recovered a cab before, All of it's sexy curves scare me. Anyone know where to find the rear panel for one (HAHA yeah right) or how to go about making one? Thanks for all your help so far.

[Colossal]

With that serial number and the rectifier being a 5X3 (four pin, full wave rectifier) it appears that your amp is an earlier model. Until the amp is properly assessed, it's not a good idea to run it lest you blow up another rectifier tube. My bet is that orange wax paper box capacitor is toast and those other two weirdo yellow caps should be swapped out with 10-22uF 450-500VDC replacement electrolytics of good quality. An amp tech should do this if you are out of your comfort zone, but don't let him/her just put anything in there. The replacement parts should be appropriate in rating and specification.

[David Root]

Based on the three 6C5, your amp is the Style 3, '37 - '41. This had a 12" speaker and an external speaker jack.

Google :: Holiday for Strings Old Gibson Guitar Amps. Check the Pre-War Section.

I checked my EH-150 build file folder, I do not have the Style 3 schematic unfortunately.
I do have also the 1969 Gibson Service Manual, which does not show it either.
It must be available somewhere!

[M Fowler]

I think this is the schematic.

[David Root]

Thanx Mark, I had not seen that mark-up before. Looks very plausible, I assume it was done from inspection of the style 3 layout?

[M Fowler]

Thanx Mark, I had not seen that mark-up before. Looks very plausible, I assume it was done from inspection of the style 3 layout?

Not sure David, I just collected all the schematics I could plus colossal and I worked together on the side trying to learn as much as we could.

[Phil_S]

For a quick lesson in applying tolex, we have one of our own, here:
https://tubeamparchive.com/viewtopic.php?t=17822
The first one I did was clearly amateur work, a speaker cab. Someday I'll strip it and do it over.

The second one, I managed to put the top on the bottom, so the seam is in the wrong place, but it came out semi-pro -- I mean darn good, but not a commercially perfect job.

There's a learning curve. You may want to send it out. If you can peel and prep the wood (needs to be very smooth and free of glue), the cost to apply the covering won't be too bad at all. If you get into it, post in the speakers and cabinets part of the forum. You'll get help.

[Reli-Teli]

I'm going to consult my engineer friend for some guidance when I need it, not if. But I'm not flipping that switch on until everything is ready to roll. I'm taking the tubes in to Moyers to get them tested, and to start looking for caps etc. I'm going to try to remove the paint with stripper, then if it doesn't work then recover. I mean hell might as well give it a shot and hopefully it won't start removing the lacquer that's covering the Tweed. As far as the handle and the back panel? I'm going to make a handle frame as they did back then and wrap it with something and some type of tape. Then take it to a local Mennonite saddle and harness shop, they do awesome work for beyond cheap and have them wrap it in leather. Thanks for the correct schematic, the tutorial and all of your insight guys. What an amp to start on, I can't wait to hear that Mic channel in person.

[rp]

you do know about these suppliers?

http://www.tubesandmore.com/
http://www.mojotone.com/
http://angela.com/

Mojo will make you a back panel all done, if it's in their database you're set, otherwise maybe someone here can trace out a template and pdf it to you with a scale on the drawing, you'd make it or send it to mojo. Worse case extrapolate from google images. One day when you come across real thing in life or web or TAG you can try again for an exact one. For the handle this is close and might fit, at least till something better comes along. http://www.tubesandmore.com/products/P-H262

If you get the paint off you can always respray or brush lacquer - plain or orange shellac, thinned, bit a time. Lots of info on web. If you strip it and it's hide glue you only need a pot of hot water a mud knife and a scotch brite sponge and rags. No sanding needed, it'll wash nice and clean. I wouldn't soak the joints. Personally I wouldn't recover it, let it be, making old things shiny new is so last millennium. It actually drops the value and desirability a good bit. The tweed will be easier to use solvents on than tolex so you could be ok, test the underside see how that comes out. Worse case you can always paint it black again

If it all goes to hell you might want to ask mojo what they want to recover it. Tweed and good glue and shipping get pricey, done pro might not be much more. Tweed needs learned skill to match up, not like tolex. If DYI try and use hide glue, it's a bitch to learn but it washes off and you can do it over easy till you get it. Many tips on the web. Practice on a scrap, it's all in small areas and timing. Someone recovering it again in 60 years will drink a beer to you for having used hide glue, or they might just paint your good work black.

Keep us posted

[Reli-Teli]

Ok, I made a trip to the electronics store today. I got 6 replacement caps so far, and 1 NOS metal 6C5 tube. I picked up some Citri Strip and started going to town on the bottom of the cab, Gettin the Tweed back then hopefully next weekend get some feedback. I checked out Mojos sight I'll have to inquire further about a replacement back. Thanks again for all the help so far guys. I'm having trouble finding the values of the 1 & 2 resistors as well as the cap going between the 2 6L6 sockets marked #3 (Newbie).

[Reli-Teli]

Ok...I can't get my pics to load. They won't even load on photobucket either. Anyways, I got most of the paint off the bottom with very little effort. I love that aged tweed. I'm having trouble finding the values of the two wire wound resistors (the cooked ones) and the cap that's between the two 6l6 sockets. Wish I had my pics I even circled everything. I'll try to get pics tomorrow.

[rp]

Make sure to wash off any remnants of the solvent, never know what harm it could do to the tweed down the road. You said the amp worked, maybe the resistors are sound enough, just cause they look toasted doesn't mean they are, you could pull them and measure, even if off it'll give you a clue. Careful, they may break if too toasted, maybe disconnect a lead connected to one and test them in place before extraction? If you have a meter that does capacitance you could measure that too, never know it might be close to spec. Like if you get .072 it's likely .05. On the other hand if you get like .093 is it .1 or .05?

One step at a time might be best advice. Do the filter caps first. See what happens, use a DBL. Measure voltages, give it a spin. Then proceed to replace other faded parts few at a time. That way if you fuck it'll be easier to back track.