12ax7 heater ground question
- Thread starter giorgi
- Start date
It depends on how the heater circuit is wired.
There are two ways to power a 12ax7. For 6.3v operation, pins 4 and 5 connect together to one side of the heater circuit, and pin 9 connects to the other.
For 12.6v operation, one side of the heater circuit goes to pin 4, the other side goes to pin 5.
There is usually some connection from ground to the heater circuit. This can be to one side only, or it could be to a center tap or a pair of resistors across the heater circuit.
So basically it may be correct, it may not be. You'd need the schematic or you will need to trace out the wiring to tell.
There are two ways to power a 12ax7. For 6.3v operation, pins 4 and 5 connect together to one side of the heater circuit, and pin 9 connects to the other.
For 12.6v operation, one side of the heater circuit goes to pin 4, the other side goes to pin 5.
There is usually some connection from ground to the heater circuit. This can be to one side only, or it could be to a center tap or a pair of resistors across the heater circuit.
So basically it may be correct, it may not be. You'd need the schematic or you will need to trace out the wiring to tell.
ok well enough, so inherently having continuity at each pin 4 to ground is not wrong. I will have to find the circuit schemes to tell for sure. This amp from Avery Fisher has phono, phase and tones daisy chained together.. I was freaked that my continuity alarm sounded between that pin 4 (any maybe 5 as you say but I forgot) and the chassis.
So you say 2 ways, in regards to there being continuity to ground the wrong way, if there was a short to ground at that pin.. what would occur?
So you say 2 ways, in regards to there being continuity to ground the wrong way, if there was a short to ground at that pin.. what would occur?
