Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.
You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login

By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username: The Name that you picked or by default, your email. Forgot Moniker?	Examples "Rapper", "Bob W", "joe@aol.com".
Password:	Forgot Password?
	Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:
Your Email:
Subject:

Message Comments

Original Message

RE: JJ 300B Quality and Reliability?

Posted by mikeyb on September 3, 2008 at 19:37:21:
I'll ignore the low DCR reference. By the way, the driver supply (+250) is regulated, with a low dynamic impedance.

Here is my concern about runing a 300B at only 53 mA. To do that, you need to have a relatively high negative grid voltage, which moves the operating point toward 'pinch off'. Not 'centered'. So you will be in danger of running into class AB rather than remain in class A, and in a less linear region.