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Re: Beginner's error

4/18/2000 7:05 AM
Rick Erickson	Re: Beginner's error It's a good idea when installing 1 ohm bias measuring resistors in an amp to parallel a 1N4007 across each resistor with the cathode to ground. This will limit the voltage across the resistor to .7V and protect the cathode resistor in case a tube shorts. I've seen a few early Fender The Twin amps with burned resistors & pc board from this problem. The later ones have the diodes but earlier ones should be fitted with them when servicing. RE

4/18/2000 7:05 AM

Rick Erickson

Re: Beginner's error

It's a good idea when installing 1 ohm bias measuring resistors in an amp to parallel a 1N4007 across each resistor with the cathode to ground. This will limit the voltage across the resistor to .7V and protect the cathode resistor in case a tube shorts. I've seen a few early Fender The Twin amps with burned resistors & pc board from this problem. The later ones have the diodes but earlier ones should be fitted with them when servicing.
RE

Replies:

Stephen Conner q{This will limit the voltage acros... -- 4/18/2000 12:49 PM