Minimum PT secondary DCR

Posted by Palustris (A) on May 27, 2011 at 13:14:48

In Reply to: Directly heated rectifiers you are hearing posted by drlowmu on May 27, 2011 at 11:25:54:

How do you reconcile your requirement for 8ohm DCR PT secondary with the tube manufacturer's recommended minimum resistance? For the 5U4GB, which has the lowest allowed resistance of any of the rectifiers listed, it is 21ohms @ 300V. For the 5AU4 it is 30ohms @ 300V. When you start to go up in voltage, the DCR requirements are much more severe: 5R4GY @ 750V is 250 ohms; 5AU4 @ 400V is 50 ohms. So even two 5AU4s @ 400V on an 8 ohm secondary would violate the manufacturer's recommendations.

Minimum PT secondary DCR for common rectifiers (Open in New Window)

This post is made possible by the generous support of people like you and our sponsors:

Follow Ups Full Thread

Topic - What's better than a 5R4GY? - andy evans 13:52:32 05/26/11 (17)

RE: What's better than a 5R4GY? - Neff 06:45:28 05/29/11 (0)

Directly heated rectifiers you are hearing - drlowmu 11:25:54 05/27/11 (2)

Minimum PT secondary DCR - Palustris 05/27/1113:14:48 05/27/11 (1)

I don't give a hoot !! - drlowmu 13:49:16 05/27/11 (0)

RE: What's better than a 5R4GY? - Al Noakes 06:01:44 05/27/11 (0)

RE: What's better than a 5R4GY? - hifipaul 05:10:10 05/27/11 (0)

RE: What's better than a 5R4GY? - Salectric 18:01:18 05/26/11 (3)

RE: What's better than a 5R4GY? - Chris O 19:29:29 05/26/11 (2)

100uF sounds like a lot!! - andy evans 22:45:58 05/26/11 (0)

RE: What's better than a 5R4GY? - Salectric 19:39:10 05/26/11 (0)

RE: What's better than a 5R4GY? - Eli Duttman 17:08:03 05/26/11 (1)

Hmmmm damper diodes. - andy evans 22:55:21 05/26/11 (0)

RE: What's better than a 5R4GY? - Tre' 14:12:33 05/26/11 (2)

This is really useful - andy evans 22:44:03 05/26/11 (1)

RE: This is really useful - Tre' 08:11:32 05/27/11 (0)

RE: What's better than a 5R4GY? - dadbar 13:57:46 05/26/11 (1)

RE: What's better than a 5R4GY? - andy evans 14:10:29 05/26/11 (0)

Follow Ups

Minimum PT secondary DCR - Palustris 05/27/1113:14:48 05/27/11 (1)

I don't give a hoot !! - drlowmu 13:49:16 05/27/11 (0)

Minimum PT secondary DCR

Post a Message!