OTL Asylum

OTL, Output Transformerless Amplifier User Group.

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: WANTED: Futterman H3 OTL project - Harvard Electronics or Tech Instruments

Posted by rogerh113 on June 25, 2022 at 09:43:20:
The boards look good - interesting all of the soldered in fuses...

You would really need to know what the rest of the amp is set up for before putting in uplevel boards. Could be that the elements that interface with the boards might be different / have different values (like voltage). Not familiar with these amps, so don't know what resides off of these boards.

Generally the transistor cans are marked. If they are easy to access, you might try good lighting and a magnifying glass. Sometimes changing the angle of the incident light helps to reveal the markings, particularly if they are old and weakly printed.