Long story short, I've done a shotgun replacement on a non-functioning V4b. I've got it running but want to weed out some noise in the preamp and on visual inspection, there is one ceramic disc on the echo board that is visibly cracked.
So what? Well, I have no clue what it is and can't locate it on a schematic. It may be of note that this cap does not appear on any V4 I've seen (as opposed to a V4B). To verify that it doesn't look to be some later addition; it's old as dirt, solder joints are old as dirt, all pictures of the V4B echo board I've found also have the cap.
You can see it here (not my amp) to the left of C203, on the lower pad of what would be R214. It is the left most component on the echo board:
![[Image: Ampeg_V4B_08.JPG]](http://www.tonecentral.net/gearpics/Ampeg_V4B_08.JPG)
In attempt to read the value, I tried to pull it out cleanly but scratched the typed face with my pliers as the leads were bent outwards.
Looks like:
4?7K
25P
I'm guessing it's a 25pF cap, but was hoping to confirm this against a schematic.
So what? Well, I have no clue what it is and can't locate it on a schematic. It may be of note that this cap does not appear on any V4 I've seen (as opposed to a V4B). To verify that it doesn't look to be some later addition; it's old as dirt, solder joints are old as dirt, all pictures of the V4B echo board I've found also have the cap.
You can see it here (not my amp) to the left of C203, on the lower pad of what would be R214. It is the left most component on the echo board:
In attempt to read the value, I tried to pull it out cleanly but scratched the typed face with my pliers as the leads were bent outwards.
Looks like:
4?7K
25P
I'm guessing it's a 25pF cap, but was hoping to confirm this against a schematic.