From postmaste–(at)–riodeel.com Sun Nov 8 11:36:22 CST 1998
Article: 137713 of alt.guitar.amps
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From: postmaste–(at)–riodeel.com (Ned Carlson)
Newsgroups: alt.guitar.amps
Subject: Re: Convert from Cathode Bias 6V6 TO EL-84
Date: 8 Nov 1998 04:02:06 -0600
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On Sun, 08 Nov 1998 02:50:29 -0800, Bill Young
wrote:

>Do these require radically different bias resistors on I tried it and
>bias seems low with 6v6 Cathode resistors ….. Thanks Bill
>
>Anyone been there done that ?????

Just look at this diagram:
http://www.triodeel.com/dyna6bq5.gif
To switch between 6V6 (or 6AQ5) and 6BQ5, the cathode resistor
is changed from 250 to 130 ohms. This is a rough rule of thumb,
6BQ5’s use about half the value of cathode resistor as 6V6 does.

Ned Carlson Triode Electronics “where da tubes are!”
2225 W Roscoe Chicago, IL, 60618 USA
ph 773-871-7459 fax 773-871-7938
12:30 to 8 PM CT, (1830-0200 UTC) 12:30-5 Sat, Closed Wed & Sun
http://www.triodeel.com
Your Start Page for Tube and Tube Amp info on the net…
http://www.triodeel.com/tlinks.htm

From mathe.nospa–(at)–abelfoon.nl Sun Nov 8 11:37:01 CST 1998
Article: 137722 of alt.guitar.amps
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From: “Marc” Newsgroups: alt.guitar.amps
Subject: Re: Convert from Cathode Bias 6V6 TO EL-84
Date: Sun, 8 Nov 1998 14:43:08 +0100
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You’re correct Ned, but I would like to add a small thing:
To avoid that any unbalance in the duet of tubes might influence the bias
point of each tube, use 2 seperate kathode resistors of 250 Ohms / 3Watt.

Marc

>To switch between 6V6 (or 6AQ5) and 6BQ5, the cathode resistor
>is changed from 250 to 130 ohms. This is a rough rule of thumb,
>6BQ5’s use about half the value of cathode resistor as 6V6 does.