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Bias Supply Frying Resistors Like Bacon!

8/19/1999 12:52 PM
Mook	Bias Supply Frying Resistors Like Bacon! It's a Homebrew (2xEL84) using a Hammond 1620 OT and a Hammond 272FX PT (300-0-300 at 150mA) . I took a bias supply "tap" from the Rectifier pin #4 (which is direct from the Main PT secondary). I used the Fender DR bias supply circuit. The first bias resistor off the "tap" (which is a 2W 470ohm) keeps frying. Any ideas? Added info: I'm using a 4007 diode (which is installed so it "points" to the PT "tap") The e-lytic is a 50/50 (I have this installed backwards, so the "+" goes to ground) Thanks, Mook

8/19/1999 12:52 PM

Mook

Bias Supply Frying Resistors Like Bacon!

It's a Homebrew (2xEL84) using a Hammond 1620 OT and a

Hammond 272FX PT (300-0-300 at 150mA) .

I took a bias supply "tap" from the Rectifier pin #4

(which is direct from the Main PT secondary). I used

the Fender DR bias supply circuit.

The first bias resistor off the "tap" (which is a 2W 470ohm)

keeps frying.

Any ideas?

Added info:

I'm using a 4007 diode (which is installed so it "points" to the PT "tap")

The e-lytic is a 50/50 (I have this installed backwards, so the "+" goes to ground)

Thanks,

Mook

Replies:

Steve K Seems like 470 is way too low for t... -- 8/19/1999 2:57 PM
Carl B. Hey Mook.470 ohm ri... -- 8/19/1999 3:00 PM
John Stokes Mook, look at the Princeton Reverb ... -- 8/19/1999 5:22 PM
Mook AAAAHHHH!!! Could I have FRIED my PT??? -- 8/19/1999 11:10 PM