JJ100... OOPS

[bhyatt1]

I got my JJ100 in (used) just a week ago... I played it and decided I wanted to mod the fixed resonance to switch out the extra cap paralleled to the stock BE cap. Worked great piggybacking off of the board and lifting one end of a cap. Next day, I decided to do the adjustable NFB. To do this and make things look neater, I , first, removed the resonance caps and installed those on a 3 way toggle and decided to pull the NFB off the board, as well. This is where I screwed up. I pulled the wires from the presence and NFB and run those under the board to the 2 pots, now where the recording out was removed. After this, my resonance no longer works, and I'm barely getting sound. Anyone have a pic of their board so that I can reconfigure back to the way things were. I know where the caps and 220k resistor go, however i need some insight on where the original wires went to which holes under these caps and resistor. I should have noted and taken photos, but I thought a schematic would be much easier to find. Thanks for any and all help. I'll probably get scolded, hopefully not by Mr. Racksystems himself

 

[Snave]

I would just email Dave. He'd know better than any of us.

friedmanamps@gmail.com

 

[psychodave]

Post up some pics of what you did. Likely one of us can help. Doing a NFB pot / mod is super simple and can really tone shape things. Just note that all capacitors aren’t created equal and will sound different. I suggest using a ceramic cap with the NFB pot in Jose style amps.

 

[RedPlated]

I'm fairly certain a JJ100 is not a not a Jose circuit.

I'm not completely understanding what you’re trying to articulate here. But if you are looking for the solder pad to connect the presence and NFB connections that should be fairly easy. It’s a Marshall power section. The NFB is derived off of the backside of the 10k PI tail resistor where it intersects with the .1uf AC shunt capacitor. Use a multimeter continuity tester to find this location. Should take a few seconds.

Otherwise, post a photo or diagram so we can see what you’re trying to accomplish.

 

[ZEN Amps]

I got my JJ100 in (used) just a week ago... I played it and decided I wanted to mod the fixed resonance to switch out the extra cap paralleled to the stock BE cap. Worked great piggybacking off of the board and lifting one end of a cap. Next day, I decided to do the adjustable NFB. To do this and make things look neater, I , first, removed the resonance caps and installed those on a 3 way toggle and decided to pull the NFB off the board, as well. This is where I screwed up. I pulled the wires from the presence and NFB and run those under the board to the 2 pots, now where the recording out was removed. After this, my resonance no longer works, and I'm barely getting sound. Anyone have a pic of their board so that I can reconfigure back to the way things were. I know where the caps and 220k resistor go, however i need some insight on where the original wires went to which holes under these caps and resistor. I should have noted and taken photos, but I thought a schematic would be much easier to find. Thanks for any and all help. I'll probably get scolded, hopefully not by Mr. Racksystems himself

Can't quite follow this but the BE100 schematic is easy to find online and very, very similar to the JJ. You should be able to work it out, otherwise take it to a tech and they'll probably sort it in 20mins. Emailing Dave and expecting free tech-support for this really isn't cool IMO.

 

[bhyatt1]

No prob... Amp is fixed. Had the schematic but in a very small fortmat. Resonance and adjustable NFB works great. I had been up all night. Clear headed today, and everything is completely finished.