Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: Billythekid on April 09, 2018, 07:01:41 PM

Title: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 09, 2018, 07:01:41 PM
My ea 600 rvt epiphone 1966 solid state guitar amps volume is very weak for being a 100 watt 110v 60 cycle guitar amp can anyone help me find the problem
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: DrGonz78 on April 10, 2018, 04:49:50 PM
Post the schematic or we will have little to no way of helping. Also, it will get a bit confusing having more than one thread asking questions about the same thing.
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 10, 2018, 06:02:42 PM
Ok i will post the schematic there are photos in the othe post of mine but i had to pay and download shcematic to my gmail inbox there are two sets set a and set b mine follows set b
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 10, 2018, 06:05:37 PM
Schematics
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 10, 2018, 06:08:32 PM
Hope u can help me man i really like this amp and want to get it back to sound great. Its been alot of reading and searching to figure it out
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: DrGonz78 on April 11, 2018, 03:59:02 PM
Wow a great schematic indeed. Do you have a voltmeter handy? You need to check all your power supply voltages and make sure that all checks out good. After that you need to consider how you can go about signal tracing the amplifier. Scopes are the preferred manner by which amp techs use to trace a signal through a circuit. If you do not have a scope then you need to google the term "Signal Tracer" and build a DIY version. These two steps will get you going in the right direction.

P.S. You only need one thread here about the amp you are fixing. If anything posting many threads about the same amp is just confusing "US", the people trying to help.
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 18, 2018, 09:19:38 AM
Ok bought a multimeter. How do i check the power voltages across the circuit? Im great at directions and know about the risk and safety. Whats up.
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 18, 2018, 09:31:21 AM
I built the signal tracer i downloaded a function generator. And a oscilloscope. Can i attach the tracer to the phone w the app and use it that way? Phone as oscilloscope with s.tracer attached to phone maybe earphone jack or usb ?? 
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: J M Fahey on April 19, 2018, 04:17:20 PM
Smartphones are wonderful but not they cann do *everything*  and *at the same time*:

Simplest test instrument is generator, I would play this MP3 file https://www.mediacollege.com/audio/tone/files/440Hz_44100Hz_16bit_30sec.mp3 from *any* other player you have available, say an old "pendrive MP3 player" to an old phone to netbook/computer/tablet , so you free the phone for higher purposes.
Set player to continuous/loop/Repeat 1 because it lasts 30 seconds, so it self restarts all the time.

As of the scope, not sure *how* will you get signal inside it, does it  have an external mic/line in?

If it only can get signals "in the air" , through its voice microphone, it´s not much more than a toy.

If you have a Laptop or PC available with such inputs, then it´s a different situation.
Title: Re: Can wrong wiring cause volume drop ind ss old amp
Post by: Billythekid on April 20, 2018, 03:48:04 PM
Thanks for getn back to me im with you.as for the generator i have a function generator that allows signal to go out the headphone output jack. Ive also built a signal tracer test probe from online video schematic. So it gos func.generator or the file you provided out of a sound source mp3 amp small bluetooth player.  Where do i go from there?? Signal tracing?? I have multimeter as well.