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previous: JCS Thanks for the reply Matt. Yes that... -- 4/7/2000 8:36 PM

Re: Plate voltage on BFD

4/7/2000 9:00 PM
Troy	Re: Plate voltage on BFD Hi JCS: 439Vdc is not unheard of for Deluxe's. I would measure your screen voltage and see if it's higher than your plate voltage. If it is then I would install 1K-2K/2W screen resistors in place of the 470ohm one's (in fact, I would do this anyway!); right on the tube socket. Right now with 439Vdc on the plates and 28ma's of current per tube your running those 6V6's at they're limit (439*.028A=12.3Watts of dissipation per tube). I would back the current down to about 24ma's and recheck everything. Since you're running good NOS tubes, I wouldn't worry about the voltage too much. If you're really worried, try a 5V4G rectifier and that will bring the voltage down a little, but not as much as a 5Y3. I personally like good 5AR4's.

4/7/2000 9:00 PM

Troy

Re: Plate voltage on BFD

Hi JCS: 439Vdc is not unheard of for Deluxe's. I would measure your screen voltage and see if it's higher than your plate voltage. If it is then I would install 1K-2K/2W screen resistors in place of the 470ohm one's (in fact, I would do this anyway!); right on the tube socket.

Right now with 439Vdc on the plates and 28ma's of current per tube your running those 6V6's at they're limit (439*.028A=12.3Watts of dissipation per tube). I would back the current down to about 24ma's and recheck everything. Since you're running good NOS tubes, I wouldn't worry about the voltage too much. If you're really worried, try a 5V4G rectifier and that will bring the voltage down a little, but not as much as a 5Y3. I personally like good 5AR4's.

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D I've often wondered about swapping ... -- 4/7/2000 10:47 PM