Model 20

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Model 20

morzh
Odobenus rosmarus

Posts: 15,810
Threads: 553
Joined: Oct 2011
City: Jackson, NJ

#13

01-09-2014, 03:33 PM

Greg

Actually speaking of bias, whether connected to Chassis or to B the centertap will be sufficiently negative towards the cahodes (filaments) as, as you cn see, the filaments connect to the C voltage which is biased towards B using the 1-2 section of the big resistor #26 which is 1.4kOhm. The output tubes being the heaviest drawers will likely self bias enough for the grids to be negative. However you are right to reconnect the centertap to B as this is what is required by the sch.
Which brings up this question: is the mentioned resistor 1.4k as required?

(This post was last modified: 01-09-2014, 03:34 PM by morzh.)

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Messages In This Thread

Model 20 - by gregb - 01-07-2014, 12:06 PM

RE: Model 20 - by Mondial - 01-07-2014, 04:46 PM

RE: Model 20 - by gregb - 01-07-2014, 05:24 PM

RE: Model 20 - by gregb - 01-08-2014, 07:08 PM

RE: Model 20 - by Mondial - 01-08-2014, 10:13 PM

RE: Model 20 - by gregb - 01-08-2014, 10:55 PM

RE: Model 20 - by gregb - 01-08-2014, 11:46 PM

RE: Model 20 - by morzh - 01-09-2014, 12:05 AM

RE: Model 20 - by morzh - 01-09-2014, 12:09 AM

RE: Model 20 - by gregb - 01-09-2014, 12:18 AM

RE: Model 20 - by morzh - 01-09-2014, 12:17 PM

RE: Model 20 - by gregb - 01-09-2014, 02:15 PM

RE: Model 20 - by morzh - 01-09-2014, 03:33 PM

RE: Model 20 - by gregb - 01-09-2014, 03:44 PM

RE: Model 20 - by gregb - 01-09-2014, 03:46 PM

RE: Model 20 - by morzh - 01-09-2014, 07:04 PM

RE: Model 20 - by gregb - 01-11-2014, 12:57 AM

RE: Model 20 - by morzh - 01-11-2014, 11:30 AM

RE: Model 20 - by BrendaAnnD - 01-11-2014, 06:07 PM

RE: Model 20 - by morzh - 01-11-2014, 06:51 PM

RE: Model 20 - by gregb - 01-11-2014, 09:40 PM

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