How to calculate breeder resistor value?

[chris ma]

Hi,

After I turned off the amp, there is always some DC value at the binding posts, that is without connecting to any speaker though.
I tried some white resistors to drain it while measuring it as well the DC value go back up to 50mV as soon as the white resistor is disconnected from the binding posts.

I remember I read something like breeder resistor intalled in the PSU to drain power. How do I intall it and how to calculate power and ohm value for the resistors? I am using CLC unregulated power supply for a Class A amp.

Thanks in advance,
Chris

 

[Netlist]

Hi Chris,
This looks like a neat little circuit. It's a bit more then a simple resistor. The advantage is that the resistor only works when powering off the unit.
http://hjem.get2net.dk/aaholm_audio/schems/discharge.htm

/Hugo 🙂

 

[grataku]

that would be called a "bleeder" resistor...

 

[chris ma]

Thanks Hugo,
That's a neat idea. I already have a small transformer for the soft start relay in the PSU. I can just add a second relay for the bleeder resistor by tapping into the same 12V supply.


grataku,
My typo



Thanks
Chris