Teemuk, thank you.  That is a plethora of information I didn't know I needed, but definitely useful and wanted.  I've had this amp for years and, until several years ago, never saw another one remotely like it.  And to find info about it on the 'net??  It might as well not have even existed.  Maybe you should write a book on the early years of Randall... : :cheesy:

And phatt, thank you.  You've re-centered my quest to (hopefully) make this thing work. 

Quote from: g1 on October 11, 2018, 09:00:51 PM
Have a look at this thread, I think the schematic should be very similar:

https://www.ssguitar.com/index.php?topic=4236.0

I took a better look at the schematic and found one part of the question, as in what type of pot(s) they are.  Unfortunately, no indication for the brand.

Also, the other dude that also had a Randall Comander I, where'd he go?  I wish he'd stuck around longer.

Quote from: galaxiex on October 10, 2018, 10:19:33 PM
Also, I bet those are Centralab pots.

Pull one and I bet it says Centralab on the bushing right under the threads.

Finally took out the chassis again tonight, pulled several pots and found that they are not, in fact, Centralab pots but CTS.  So good news / bad news...
- the good:  they are (hopefully) still made, or some equivalent
- the bad:  I still don't know what their specs are

I thought about just switching the pots from the left channel over to the right channel, but now I'm having second thoughts about that.  It's late, I'm tired, and I'll more than likely screw it up or do something else equally stupid.

Front:

Not that I could see.  Of course that one silver-ish sticker is faded, but it probably wouldn't be on that.
Back

Quote from: galaxiex on October 10, 2018, 10:08:32 PM

Quote from: g1 on October 10, 2018, 09:56:32 PM
How about a pic of the front panel showing control names.

And the rear panel.

That amp chassis looks suspiciously like a CMI product.

Very similar to some Gibson SS amps from the 70's.

Also, what's up with those 2 loose lock washers just laying there?
Right by the power switch!!!
First pic, second set of pics.

Actually those washers are in all the pics, just more obvious in the close-up.

Whoa! After comparing pix of yours to mine... the similarities are too great.  Maybe Randall were making amps for Gibson at that time, and simplified things by using the same design.  I'm speculating, of course.  I was just a tot back then, soiling my Pampers.

I did remove the washers, seeing  how they could cause more problems.

Several things I did notice after taking out the control board (?) / chassis (?) was:
- how much space was used for the circuit board.  If things need to be replaced, this makes it easy
- one of the capacitors has a hairline fracture going through it.  Can that be a problem?  I'm assuming it's ceramic.
- two of the pots on the second channel (reverb and tremelo side) could be problematic.  Specifically the middle tabs of both the treble and mids pots.  Usually there would be numbers on the back specifying what the type of pot it is; these are blank.

When possible, I will upload pix of the front panel.  Right now, I'm having a little trouble with the internet.

Any other details?

More inside pix:

Sooo...

I was looking at the amp the other day, and suddenly remembered about this post.  It's only been about 9 months, some vehicle problems, a move, work and the usual distractions that come with life and family.  I apologize to all of you that want to help, or are the least bit curious about this beast

This being the internet - no pics, no proof:

Good morning and such.  It was by chance that I found this forum, and maybe, hopefully, find some answers too.  I have an 1974 (maybe) Randall RG 90a-115 amp that is mainly a mystery to me.  I can barely find any info about it except for a few other lonely fans that have similar Randall's from that era, which have sustained my hope all these years.

I just recently replaced the 15" speaker with a brand new Eminence (thanks TDPRI, I should get back there and give them an update and thank you), but in doing so, i found that the amp has other problems as well.  The left (1st channel?) sounds dull and muffled, like a wet towel is in front of the speaker.  Ive also noticed that the bass and treble pots on that side don't seem to work as well.  The right (2nd channel?) works, but after the first 2-3 minutes starts the loud popping and snapping, and only seem to stop after I turn both the bass knob off and volume knob down to about 3.  Tremolo works, which my 12 year old son gets a kick out of, and reverb input doesn't, which i'm ok with...I probably need a new RC plug for that side.

If I can get just 1 side working (tremolo side preferably), I would be a reasonably happy man.

Soooo...anyone out there willing to help?