• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Fisher 400 convert 7868 to 7591 cathode resistor?

making crap

New Member
I installed new octals. There is a larger pwr resistor 1200 ohm coming off the 7868s to transformer outputs (red wire) . Not sure what to do with it. I don't see it on the schematic. It seems to be hooked to the screen pins all wired together with this resistor going to the red transformer wire (output). The screens are powered by an orange wire coming from the power supply. Nobody talks about this resistor? How would it be hooked to 7591s
 
Register to hide this ad
That should be the resistor between power supply nodes. This one I believe

1790970558075.png

if you're converting this to a 7591, it still powers the screens, but pins 4 and 8. There should also be a wire running from the chain of screens back to a cap in the power supply.
 
Back
Top Bottom