I have a Bally Squawk and talk board which is not working. There is no -5v. So I'm thinking of replacing the -5v regulator. Question I have is: C47 and C48 connect to the -5v regulator. In the manual they are listed as ceramic 0.01uf 25v. On the actual board, they look like resistors...is this just a style of capacitor that I'm not familiar with, or is it a resistor?
20220629_185356 (resized).jpgYes, caps can come in packages that look like resistors.
https://en.wikipedia.org/wiki/Electronic_color_code#Capacitors
Before replacing it, have you confirmed that the regulator has the proper voltage on the input pin? If it’s correct (and not too much ripple) then it’s probably bad, but it’s also possible that there’s a short or something overloading the -5v supply.
The -5v regulator rarely fails. It’s usually the two 330uf caps in that circuit or the two diodes cr7 and cr8 I think, Which would cause the wrong voltage at pin 1 of the regulator.
Midway made the boards for Bally and relied on an auto insertion robot to stuff the circuit boards. Each machine used a different tool to install different types of components. By the late 70s component manufacturers started packaging components in similar bodies so the parts could all be machine populated without changing tools. While confusing to us humans the robots could tell the difference. 
have you looked at the rear of the board for dry solder joints on the headers?
it could be the pic but the left hand pin of the 7905 appears to have a circle in the solder where the leg meets the pad?
Quoted from jj44114:The -5v regulator rarely fails. It’s usually the two 330uf caps in that circuit or the two diodes cr7 and cr8 I think, Which would cause the wrong voltage at pin 1 of the regulator.
As a rookie and desperate solution, I have replaced both 330uF caps, both diodes and the -5V regulator.
The input voltage is low at -2.4V dc.
GI voltage is 5.7 V ac at pin 7 on J1...I'm wondering if the problem is with the GI return connection? Or the Earth connection...I will investigate further today
Quoted from pinpal:As a rookie and desperate solution, I have replaced both 330uF caps, both diodes and the -5V regulator.
The input voltage is low at -2.4V dc.
GI voltage is 5.7 V ac at pin 7 on J1...I'm wondering if the problem is with the GI return connection? Or the Earth connection...I will investigate further today
After a bit of furtling, I have - 5V. Probably a poor connection on a Molex connector on the back box.
So, now I have all the correct voltages (tp2=5V, tp3=12V, tp4 =-5V)...Unfortunately the squawk and talk LED is locked on. No flicker, just on...
Any suggestions greatfully recieved with thanks
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Tenby
Palatine, IL