Bob,

I've had an RS-20A for over 20 years and an RS-35A
for 7 years.  Both can be  noisy and there is a vibration  you can feel if 
you touch the top cover.  I've found that just  moving it around  a bit can 
reduce any noise, although I've never experienced the roar you describe. 
They also both clunk pretty good when powered up.

73, Steve KW3A

----- Original Message ----- 
From: "Bob Martin" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, October 13, 2008 8:13 PM
Subject: DC Power Supply Roar


> Earlier today, my almost new ASTRON 35 developed a really loud roar under
> load.  It had been on receive for 2 or 3 hours.  Then, At 5 Watts transmit
> on FM,  it was hardly noticed.  At about 40 Watts it is quite lout and at
> 100 continuous it can be heard throughout the entire basement. Just now, I
> turned it on and went through the cycle noted above with no noise heard. 
> In
> stand-by I can't hear it at all now but when I was experiencing the 
> problem,
> I could feel it vibrating ever so slightly.  Will try it before I turn in
> tonight.
>
> Any thoughts?
>
> 73
> Bob Martin
> KC3FI
>
>
> EchoLink Node - 55127
> Please visit http://www.wan-leatonks.net.
>