Connect a 10v Zener between the source (anode) and the gate (striped end),
Do you have any fast recovery diodes? Something like a 1n4148 may work.
How fast do the input and output voltages for the 7812 regulator for the 21844s drop, in relation to the remote being removed. Check this in differential mode with probe 2 on the negative rail.
Do you have any fast recovery diodes? Something like a 1n4148 may work.
How fast do the input and output voltages for the 7812 regulator for the 21844s drop, in relation to the remote being removed. Check this in differential mode with probe 2 on the negative rail.
The jfet needs to have positive voltage (relative to its source) to be switched off. 0v to switch on. The 12v regulator voltage wasn't dropping quickly enough.
The jfet has a limited voltage that it can withstand at its gate. The Zener is there to protect it. It will always remain connected across the jfet gate and source.
The 1N4148 is going to supply voltage from the transformer to the gate of the jfet via the resistor. This voltage will drop much quicker because there is no capacitor when the PS switches off
It's D22 on the AQ20 diagram (may be different in your amp). There are 4 diodes (including D22) that are connected to a dedicated winding on the power transformer. The diodes are sometimes near the transformer and sometimes near the 7812.
The jfet has a limited voltage that it can withstand at its gate. The Zener is there to protect it. It will always remain connected across the jfet gate and source.
The 1N4148 is going to supply voltage from the transformer to the gate of the jfet via the resistor. This voltage will drop much quicker because there is no capacitor when the PS switches off
It's D22 on the AQ20 diagram (may be different in your amp). There are 4 diodes (including D22) that are connected to a dedicated winding on the power transformer. The diodes are sometimes near the transformer and sometimes near the 7812.
This is likely not going to be a viable solution due to requiring a bit too complex but it may lead to a better solution.
0.15v may be a meter error.
Try paralleling a very small capacitor (0.001uF) across the Zener. Does that prevent any rail dumping?
Are you sure that the rails didn't drop approximately the same when the driver ICs were disabled?
0.15v may be a meter error.
Try paralleling a very small capacitor (0.001uF) across the Zener. Does that prevent any rail dumping?
Are you sure that the rails didn't drop approximately the same when the driver ICs were disabled?