Altair 680 power supply...

[Ian King]

And you have some other problem if the output side of a 7805 is showing anything other than five volts.  You should be able to feed anything into it up to its maximum rating of (if memory serves) 40v and get 5v out.  If there isn't anything in the ground path of the 7805, replace it; if there is (for instance, a pot or diode, or any sort of active circuitry), check it carefully.  -- Ian 
________________________________________
From: cctalk-bounces at classiccmp.org [cctalk-bounces at classiccmp.org] On Behalf Of Chuck Guzis [cclist at sydex.com]
Sent: Saturday, January 16, 2010 5:57 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Altair 680 power supply...

On 16 Jan 2010 at 20:48, Bill Sudbrink wrote:

Bill, try putting a load on the output of the power supply and then
looking again.    A 12V automotive tail or brake light bulb might do
the trick.  These supplies were designed to run with a load.

--Chuck