[Premium-Rx] Collins HF-2050 power supply

[Jan Skirrow]

On 11/22/2012 4:57 AM, Karl-Arne Markström wrote:
> Gentlemen,
>
> This is to advise of a quite nasty problem with the HF-2050 power
> supply.
>
>

The heat generated by the stock HF-2050 power supply poses a serious 
problem to the aging electronics, and the kind of failure Karl-Arne 
noted could cause serious damage.

These radios were typically mounted in closed rack cabinets with serious 
forced air cooling of what was often a stack of radios. Running one 
without any cooling is asking for trouble, and I'm told heat related 
failure was the biggest problems these radios faced in service. Some 
years ago, a friend asked me to see what might be done. A switching 
power supply is a possible solution, although it would have to be very 
quiet (RF), and most are not. The other option was to mount muffin fans 
on the outside of the perforated case, but I decided this was not a good 
solution, as it took a lot of airflow to bring the temperature down to 
what I thought was a reasonable level. My solution was to simply remove 
the power supply from the case, mount it on a 5" rack panel and put in 
on the rear of the 19" rack cabinet my friend used for his radios. Even 
with open sir cooling, the power supply operated at a more reasonable 
temperature (I could have added a fan if I really wanted to bring it 
down) and the radio itself operated very cool. I think my friend used 
this arrangement for some years, and may still be doing so!

I posted a brief write up on my website, with pictures.

Cheers

Jan Skirrow, VE7DJX

http://skirrow.org/Boatanchors