sweatyk 7/28/2018 8:32 AM
5150 Combo Chassis
I'm trying to remove the main pcb's to inspect for bad solder joints. I have everything removed that would hold it in. Obviously it is not going to come out very easily. If the pots were about an 1/8" shorter it would drop right out. Any suggestions as to the best way to get it out? It doesn't lack much but just enough to make me start drinking again.....lol. GRRRRRRRRRRRRRRRRRRRRRRRRRRR
Enzo 7/28/2018 9:19 AM
It is arranged like a Classic 30. The boards form a three sided structure. If there is a jack board in the way, pull it out, but we then bend the sides towards one another. Push the socket board towards the controls board. Collapsing the three sided bit this way allows more clearance.
sweatyk 7/28/2018 9:52 AM
I finally got it out. My post was pre-coffee. I realized that the jack board had to come out. Upon investigation all solder connections look pretty good. A sketchy one on C30 but that's it. The symptoms are when you switch it from standby to on it has this distorted cascading wave for a second or two. The sound is low and can only be adjusted by the pre volume on both channels. Both post volumes do nothing and the tone is all treble with no mid or bass. Does this sound like a classic symptom? A few months ago it kind of gave me a small preview of these symptoms. I deoxed all of the tube sockets really good and it seemed to have cleared up so I thought. Any recommendations or where to start? Visual inspection did not turn up anything obvious.
Jazz P Bass 7/28/2018 10:27 AM
I would suggest that you start with the power supply.
Check all nodes for excess Vac ripple (especially the preamp).
Enzo 7/28/2018 12:09 PM
And isolate the problem. You have FX loop jacks, so determine if the problem is before or after that point. Essentially is it the preamp or the power amp.
sweatyk 7/28/2018 7:13 PM
Thanks guys.....while I have it apart and access I'll clean al the pots, jacks, and tube sockets thoroughly. Then put it back together to start troubleshooting.