Allen Accomplice Staticing, Popping, ocillating and then Clearing Up

[Platefire]

I've been dealing with this last couple of weeks as it is my amp at Church. At first I thought it was patch cords/guitar cord that I was tinkering with trying to find the source but this Sunday I finally pulled out the cord from the effects and went straight into the amp input and it was still acting up. After a few minuets it clears up and starts acting normally.

What it does is when you first turn it on it starts getting light static with no signal, and then when you try to play through it the static turns to popping that graduates into a oscillating hum. Then you can put it on standby a few minuets and then turn it on and everything is fine, normal operation and no hum.

I will bring it home this next week and give it a going over. The first thing I will probably check is V1 and go from there. Any of you guys want to venture a guess what it is and see who nails it? I think I'm going with V1 going bad or either V1 socket needs cleaning. Platefire 

[shooter]

socket needs cleaning

even money says it's sockets, or jacks, or other mechanical   
longshot money on gassey tube

[Platefire]

OK, got ya! All my amps have been working so good, no trouble shooting action around here. But I'm not complaining. I did try to fire up one of my Silvertone 1482's recently and the mic channel didn't work. I ended up pulling the chassis and loosened the input jack checked connections and everything seemed ok, when I put it back in and tightened it again it was working fine. It maybe lost ground?  Oh, the joys of retirement life. Platefire

[shooter]

maybe lost ground?

my new build doe's weird stuff when I 1st power on, like a missing ground, fil hum, just noisy but signal is always there, and within 30sec to 2 minutes, gone. play for hour, quiet.  I'm betting on KT88 showing it's age and my abuse, or static built up in all those caps inside the guitar cable 

[jjasilli]

Always suspect tubes 1st.


Use a scope or listening amp at successive stages to locate the source.

[Platefire]

Oh No!!! I went and picked up the amp and got it home. It's working perfect. No hiccups at all!

That only leaves the Guitar!  I can't believe the guitar was doing all that. I'll have to go back and get that and test it now. Wow this game of cat and mouse is getting old quick but-------I will get to the bottom of it I reckon if I keep on pluggen. Platefire

[John]

Or, in transport you jostled something back into "good contact".


Although, I did once drive myself nuts trying to figure out why I was getting no sound, then realized the vol pot on my test guitar had a dead spot. 

[Platefire]

Could very well be as you said! When I first got this guitar that I have been using over this amp, I had a problem with the output jack wires making contact with each other and I corrected that by moving them around to get separation plus when I plug a cord into that jack seems kind of loose. So I thinking very strongly that well may be the culprit but---it seems like every time I got it----it moves. I'll keep chasing it! Platefire

[sluckey]

when I plug a cord into that jack seems kind of loose.

Replace that jack with a Switchcraft jack and throw that loose jack away. I learned a long time ago to not use cheap jacks. They make lot's of crappy sounding noises on inputs and are dangerous when used for speaker jacks. Back in the '70s Radio Shack jacks were notorious for being sloppy fit. The barrel was just not a precision fit for the plug.

[jjasilli]

Oh No!!! I went and picked up the amp and got it home. It's working perfect. No hiccups at all!

That only leaves the Guitar!  I can't believe the guitar was doing all that. I'll have to go back and get that and test it now. Wow this game of cat and mouse is getting old quick but-------I will get to the bottom of it I reckon if I keep on pluggen. Platefire

That's Ok, it happens to everybody. 


+1 to sluckey.  I used a cheap old jack I had laying around for a speaker build.  Then the speaker wouldn't work.  It was a PIA to trace the problem to that jack.

[Platefire]

I picked up the guitar today. Well I went through my stuff, and did find a New Switchcraft Mono Jack. So I installed that and now the thing is so tight you really have push hard to get it in and really pull to get it out---no slack for sure. Guitar presently has no static or popping through the amp. 

I will be taking that guitar and amp back to Church and give it the road test this next weekend and hopefully it won't be doing any more acting up. Thanks, Platefire

[Platefire]

I played through the subject rig at Church today and
Everything worked great. So it appears that the whole
Problem was in the guitar jack. Thanks, Platefire