[ICOM] RS 70A PS

[Mort Arditti]

Fan noise can indeed by annoying.
My RS 35 did not have fans and the heat sinks did get very hot with
heavy load. I installed two temperature controlled fans (home brew).
The heat sinks remained cooler, but there was noise. The fans were
rated at 12 VDC. Lowering the fan voltage to about 9 - 10 makes them
run slower and less noise. A series resistor or zener diode (for DC fans)
works great. A solid state temperature on of the power transistors
sensed temperature and a comparator with hysterisis activated the fans.
Nothing elaborate.

Mort, KB6BSN


----- Original Message ----- 
From: "K2SNJ" <k2snj at comcast.net>
To: "ICOM Reflector" <icom at mailman.qth.net>
Sent: Tuesday, June 29, 2004 10:42 PM
Subject: Re: [ICOM] RS 70A PS


>
>   I have been using the Aston RS-70M for 10 years now. GREAT supply! Yes
the
> fan only comes on when it is needed. I have only had it come on during
> contest operation or lots of RTTY operation.If the fan is to noisy for you
> put the powersupply on the floor under your desk and you won't hear
> anything. Sure beats the hell out of that junk Icom - 125 supply.
>
>
> ----- Original Message -----
> From: "William Diamond" <wjdiamond at sbcglobal.net>
> To: "Icom at Mailman. Qth. Net" <icom at mailman.qth.net>
> Sent: Wednesday, June 30, 2004 12:52 AM
> Subject: [ICOM] RS 70A PS
>
>
> > Hi Folks,
> >
> > My new to me Astron RS70A power supply arrived today, what a brute....
> >
> > I did not a manual with it and can anyone tell me if the fan is supposed
> to
> > run all the time or only when it needs to?
> >
> > Oh yes, it is only running Icom's, no brand Y or K hi hi.
> >
> > Thanks
> >
> >       William J. Diamond
> >        Rogers, Arkansas
> >
> >     Ham Radio Operator WR0T
> >
> >    Please Visit My Radio Site
> >         wjdiamond.com
> >
> >
> >
> > ----
> > Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> > Icom Users Net: Sundays, 1700Z, 14.316 MHz
> > Icom FAQ: http://www.qsl.net/icom/
> >
>
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>
>
>