Help my BDRI

[shooter]

different seats at the same movie


ovals are AC, must have a signal in THAT matches schematic notes
rectangles are DC, no input required

TP3 2.015 VDC          TP6 2.005 VDC          TP9 0.0 VDC

tp3 is DC, my bad, 6 & 9 are AC(IF we're both using schematic in reply 15)

[shooter]

let's stay easy for now
do you hear relays clicking when you switch, does the led lite/nolite??

[Cramer1]

https://www.thetubestore.com/lib/thetubestore/schematics/Fender/Fender-Blues-Deluxe-Reissue-2004-Schematic-Rev-A.pdf

This is the one I am using.

[shooter]

TP9 = 0
so find V2A and figure out what PW2 is, cable?  tube socket? .......

[Cramer1]

Ok so I can hear clicking when I use the foot switch, the red light comes on with channel select, and if I crank reverb I can hear it also, but at the same low volume.

[Cramer1]

TP9 = 0
so find V2A and figure out what PW2 is, cable?  tube socket? .......

PW2A and B are the Ribbon cable connections going from the main board to the tube board for V2. So P2 would be the ribbon cable? TP9 is on the main board side of that ribbon.

[shooter]

so TP9 on main board>cable>tube socket ?
pull V2, ohm from socket pin 3,(probe where tube pin 3 was), to chassis ground

[Cramer1]

so TP9 on main board>cable>tube socket ?
pull V2, ohm from socket pin 3,(probe where tube pin 3 was), to chassis ground

I will try that. If pin 3’s socket to ground is good, could I swap V2 and V3, then run preamp out and if I get sound then, assume that V2 is bad?

[shooter]

 


it's a PCB amp, IF I make ANY assumptions, it's a poorly constructed cable/solder/foil/socket, probably one of that last things I'd assume is a preamp tube

[Cramer1]

So I haven’t gotten my meter back out, but I did swap tubes 2 and 3 and now my preamp out works.....

[shooter]

then you should have a working amp since the PA checked out yesterday, you still have bad doggy solder connection, or possibly sloppy socket pins

[tubeswell]

Maybe run the amp for an hour or two with 2 x meters clipped on the 16V dual rail PS. Look for changes in rail voltage if the channels start switching/reverb cuts in and out


If you shine a torch through the board its easier to see where the heat affects other parts - here's a BD I fixed a while back (Charring is from before I replaced the resistors) note the zener 'looks' fine except for heat burn around the trace pads which only visually showed up with the torch test

[Cramer1]

Pin 3 to TP9 rings out. TP9 also has 2 VDC with the tube swap.