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Randall RG100 Classic info?

Started by TolerBear, August 04, 2014, 08:24:55 PM

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TolerBear

I'll be putting those pictures on here maybe tomorrow. If not tomorrow I'll get them up Monday. I have a gig this weekend.



J M Fahey

Quote from: TolerBear on August 21, 2014, 07:52:26 PM
Oh Lord. I just replaced all of those. Lol.

Then we´ll have to start troubleshooting instead of shotgunning ;)

As of your pictures, you show the amp exterior which *looks*  like an old ES and just one small unidentified PCB which shows it is NOT a classic Randall.
(By the way, there´s an old saying which goes: "if it says Classic or Vintage on it ... then it´s not :( )
That PCB is pupulated with SNT parts and .... horror of horrors .... two 80 or 100 pin square ICs, so there´s some heavy digital stuff brewing in there :(

Not useful for the problem at hand.

We need clean and readable pictures of the power transformer area, power supply and power amp at least.

TolerBear

No. This amp is totally analogue. Lol. It's got the older components in it. Barrel resistors, 8 pin op amps, etc.  :-)

g1


J M Fahey


DrGonz78

Quote from: g1 on August 24, 2014, 11:12:29 AM
So this picture is not from the Randall?
http://s18.photobucket.com/user/Jskrapper/media/P1120828.jpg.html

Yeah I saw that pic too at first and was not sure if it was from that amp or not. Looks like a helicopter... :lmao:
"A person who never made a mistake never tried anything new." -Albert Einstein

TolerBear

Yeah. That's from the helicopter. Lol.

J M Fahey

And how does it sound ?   :lmao:

TolerBear

Good news. I got it to turn on. It changes channels too but still no sound and that resistor I was talking about is getting way too hot and it's smoking a little, making me think it's the wrong resistor value. It acts as if to me it's got too much current flowing through it making it overheat. The other problem was I didn't realize it but one of the rectifiers had a globe of solder bridging two of the leads together.   ::)   I'm gonna try to put pictures up now of the different parts of the amp.

J M Fahey

Did you replace the Zener diode?
What voltage do you measure on each end of the resistor, relative to ground?

TolerBear

I haven't measured it yet. The amp is at work. I took it there because we have benches and better lighting than I have here at my apartment. I'll measure it tomorrow. The resistor in this picture is the original which I have misplaced. :-(

TolerBear

I haven't replaced the zener diode. Do you think I ought to? Is there a good way to check the one I have?

TolerBear

I couldn't tell what the original resistor's value was either. I'm color blind to an extent. Pastels and close colors get me every time.