Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: LazarusLong on July 02, 2024, 06:01:08 pm

Title: Peavey Delta Blues 210 Static like noise
Post by: LazarusLong on July 02, 2024, 06:01:08 pm
Hello. I am having an issue with a Peavey Delta Blues 210. I just replaced the large electrolytic caps. I also cleaned the pots, switches and tube sockets. The re-cap has cured the red plate problem. But, there is now a staticky/popping issue happening. The amp powers on quietly. Then after about 10 seconds, a static wind can be heard through the speakers. There is also a loud pop when the channel button is pressed, and most of the controls are a bit noisy. They shouldnt be very noisy at all after cleaning.

I have swapped tubes with 2 different sets of known good tubes. No change.

Any suggestions on where to go from here would be much appreciated!

Title: Re: Peavey Delta Blues 210 Static like noise
Post by: shooter on July 02, 2024, 08:18:46 pm
how many connectors are inside?
bad mechanical connection somewhere?


I looked at a 212 schematic, quickly, what's your skill set?  You can get flames real quick in a Peavey if you're not on your A game
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: LazarusLong on July 02, 2024, 08:58:32 pm
how many connectors are inside?
bad mechanical connection somewhere?


I looked at a 212 schematic, quickly, what's your skill set?  You can get flames real quick in a Peavey if you're not on your A game

How many connectors? Im not sure what you mean by that? There are six different plug type connectors. They are all connected properly..

I also just opened it back up and ised a non conductive probe to test if any of the linking wires between the boards were loose. They all seem fine.

The amp sounds great aside from this noise. Its not extremely loud, but there is no mistaking that its there.

My skill set? Im not totally incompetent. Amateur hack with the ability to learn might be close? Lol
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: sluckey on July 02, 2024, 09:42:58 pm
Does this look like your amp?

     https://el34world.com/charts/Schematics/files/Peavey/Peavey_deltablues.pdf
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: AlNewman on July 02, 2024, 11:30:00 pm
Go through and check all the solder joints and connections.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: Latole on July 03, 2024, 03:34:53 am
Go through and check all the solder joints and connections.

I agree .

Peavy amps are hard to service

Good picture of the circuit if you click ; https://el34world.com/Forum/index.php?topic=23543.0
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: tubeswell on July 03, 2024, 11:36:47 am
Go through and check all the solder joints and connections.
Peavy amps are hard to service


I won’t touch them anymore.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: Latole on July 03, 2024, 02:49:03 pm
Go through and check all the solder joints and connections.
Peavy amps are hard to service


I won’t touch them anymore.

Same for me.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: LazarusLong on July 03, 2024, 05:02:46 pm
I played it for about 30 mins. The noise seems to be most effected by the reverb. More reverb more noise. But even with that said, the noise did decrease after about 5-10 mins of play. I ordered a few more caps and will dig back into this when they come in.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: Latole on July 03, 2024, 06:47:57 pm
I played it for about 30 mins. The noise seems to be most effected by the reverb. More reverb more noise. But even with that said, the noise did decrease after about 5-10 mins of play. I ordered a few more caps and will dig back into this when they come in.

I will replace 330K tubes plates resistors.
IMO caps are good or not all the times.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: AlNewman on July 03, 2024, 07:57:00 pm
Have you tried changing tubes?  Could be all it is.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: Latole on July 04, 2024, 03:16:50 am
Have you tried changing tubes?  Could be all it is.


LazarusLong  write ;"  ....The re-cap has cured the red plate problem."

Red plating on EL84's has nothing to do with a re-cap. if you talking about filter caps
Red plating is because tubes working too hard ( too hot bias ) or they are short / at the end of their life.

Chance you waiste you time and customer money with new filter caps.


Those amp may have few issues before you work on.
1- Check EL84' s bias  and report here
2- Re-heat all you solders
 

 
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: LazarusLong on July 12, 2024, 04:11:39 pm
Have you tried changing tubes?  Could be all it is.


LazarusLong  write ;"  ....The re-cap has cured the red plate problem."

Red plating on EL84's has nothing to do with a re-cap. if you talking about filter caps
Red plating is because tubes working too hard ( too hot bias ) or they are short / at the end of their life.

Chance you waiste you time and customer money with new filter caps.


Those amp may have few issues before you work on.
1- Check EL84' s bias  and report here
2- Re-heat all you solders

Well, I dont know what to tell you. There was an issue with one of the el84s red plating, (and yes, I swapped tubes out before doing the recap), and after replacing the caps, that issue disappeared. The way the amp was acting before the recap didnt allow for the issue in my original post to even be heard.

I am not doing this for a customer. So dont worry, the only money being wasted is my own.
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: shooter on July 12, 2024, 04:17:39 pm
so what's the current status?
what are the tubes biased at?
Title: Re: Peavey Delta Blues 210 Static like noise
Post by: LazarusLong on July 22, 2024, 05:00:42 pm
Woohoo! I found the culprit. One of the pads under the R71 resistor had lifted. I did a continuity check on all of the bridge connectors and that one was a little questionable. I also went ahead and resoldered all the tube sockets while I had it taken apart again.

Overall this was a great learning experience, but I can see why no one wants to work on these. As most of you know, you cant perform most of the testing without removing the boards from the chassis, and then you need to disconnect the wires from the plastic connectors to get them out of the chassis in order to hook them up to test.

Anyway, its done and thanks for all of the input!