kurtsstuff2003
Active member
Just wondering?..Can a volume pot in an amp be checked while still in the circuit?
Checking a volume pot while still in the amp
- Thread starter kurtsstuff2003
- Start date
Smashedguitaris⸸
Hack
1. Stand in front of amp/cabinet
2. Turn on power
3. turn volume all the way up
for steps 4 and 5, i need you to be very fast so they are almost like the same step
4. hit a hard chord on the guitar
5. slap the standby
2. Turn on power
3. turn volume all the way up
for steps 4 and 5, i need you to be very fast so they are almost like the same step
4. hit a hard chord on the guitar
5. slap the standby
311splawndude
Well-known member
what do you mean by check?
what are you trying to do/determine?
kurtsstuff2003
Active member
Lol!! love that first response..guess I should have expanded as to what's wrong lol!..I'm 99.99% sure the volume pot on a Marshall superlead is shot in the "normal" channel. The "High treble" as they are called channel volume pot works just fine. The normal channel when turning the pot up emits a barely audible lower end type hum when cranked. Now..I know just enough about working on amps and electronics to not kill myself and hoping there is a way to check the pot via multimeter without having to yank the pot out. I'm guessing I'd have to disconnect the wire's attached to the pot lugs but hoping to avoid that.
Last edited:
311splawndude
Well-known member
I see. Well I'm not an amp tech or anything like that so take my next comment with a grain of salt. Just because you are having problems with the normal input volume, doesn't mean it is the pot. It is quite possibly something else. But when you say that are saying the guitar tone/volume is fine/normal? No pun intended there. And this hum is new and was not present before? I would be leaning more toward a faulty resistor or bad solder joint. With the amp off and pulled out you could spray a bit of electronics contact cleaner in that vol pot and roll it back and forth a bit but I have feeling that is not going to cure hum. Have you done the channel jumping trick?
(someone smart will chime in
)kurtsstuff2003
Active member
Thanks!! The reason I think it's the pot is...When on zero there;s a slight buzzing then as you turn it up it starts fading until you hit 5 on the volume knob then it goes completely silent But! as you keep turning it up from 5 the buzzing starts building up louder and louder then when on 10 it sounds like it is on zero..just weird??I see. Well I'm not an amp tech or anything like that so take my next comment with a grain of salt. Just because you are having problems with the normal input volume, doesn't mean it is the pot. It is quite possibly something else. But when you say that are saying the guitar tone/volume is fine/normal? No pun intended there. And this hum is new and was not present before? I would be leaning more toward a faulty resistor or bad solder joint. With the amp off and pulled out you could spray a bit of electronics contact cleaner in that vol pot and roll it back and forth a bit but I have feeling that is not going to cure hum. Have you done the channel jumping trick?
(someone smart will chime in
SpiderWars
Well-known member
That doesn't mean its the pot I don't think. I don't know why they do that sometimes. I've tried swapping just about every component involved (tube, pot, coupling cap, cathode cap) and no luck. Did you try a different tube? I'm wondering if that is indicative of a tiny bit of grid current on that grid connected to the wiper.
kurtsstuff2003
Active member
Yeah...I've put amps together in a "connect the dot" sort of way but..unless I can actually see whatever issue might be going on with an amp (IE: fried something cap,resistor etc..) I just don't have the knowledge of what to look for and it's just a guessing game of which I've found over the years, That that can take a small issue and create a bigger issue..lol!!
kurtsstuff2003
Active member
Thanks!..I've been a chop sticking fool for the last few weeks..lol!! Thinking I'll just go with my first intention for the amp and send it to Monomyth I've already talked to him about it and I was just going to sell it to him but..backpeddled..lol!! If I could find a decent shipping box it would probably been gone Already..lol!!
kurtsstuff2003
Active member
The amp is totally stock with no mods ...it's just one of those extremely frustrating situations where lack of knowledge bites me in the ass..lol!! I call what I do "Lucktronics" If I can fix it..I got lucky..lol!!