[TenTec] Johnson PS ??

[George, W5YR]

Sounds like a linear (non-switching) non-regulated power supply using LC
filtering. By non-regulated, I mean that it sounds like it does not use
electronic regulation to maintain the output voltage constant under varying
loads. "In the old days" all our power supplies were like that and we relied
upon the filter choke inductance and the filter capacitance to provide
adequate dynamic regulation.

If it works, use it!

73/72, George
Amateur Radio W5YR -  the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"



-----Original Message-----
From: tentec-bounces at contesting.com
[mailto:tentec-bounces at contesting.com]On Behalf Of Rich Gaarden
Sent: Sunday, February 23, 2003 2:24 PM
To: tentec at contesting.com
Subject: [TenTec] Johnson PS ??


Hi Folks,

This is off topic I suppose but the PS will be used on Ten-Tec equipment!

I acquired a very heavy 40# perhaps PS which is not properly regulated (16
V).  I was told it was from a repeater and that it was a Johnson 30 amp
continuous.  I thought this would be an easy fix.

There are heavily heatsinked diodes. There is a substantial choke and
appropriate filter caps.  There is a large two section transformer. There is
a small section which vaguely resembles a VR but there are no pass
transistors.  Anyone know how this thing might work?  Could it be a
saturable reactor?  Any one know how to regulate the output?

I realize that I'm not giving a lot of information but perhaps enough for
someone to point me towards help.  I have worked on a few supplies but never
one like this!

Thanks,

Rich  KF3DQ