[Johnson] Solid State Power Supply in a Ranger

[Bob Sullivan]

Ross,

I hope you have moved that dropping resistor out of the VFO enclosure! If 
not I suspect you are slowing cooking the VFO boards. I always relocate 
that dropping resistor to under the chassis. Some of the Ranger VFO's I 
have seen are pretty bad due to the heat generated by this resistor.

73, Bob
WØYVA
My station: http://www.isquare.com/personal_pages/hardware-14.htm


At 07:19 AM 10/18/2004, Ross Stenberg wrote:
>Tim, I know the purists would object, but I have been running my Ranger II
>with SS rectifiers and the resulting higher voltages for the last four years
>without any problems. I did however increase the value of the 18K dropping
>resistor supplying 0A2 regulator for the VFO and used electrolytic caps with
>appropriate voltage ratings throughout.
>
>         73 Ross K9COX
>
>
> >>>I’ve solid stated the power supplies and beefed up the electrolytics in
>my
>Ranger I and it’s working fine but of course the B+ voltages are now too
>high. (Around 800 on the high B+ and 600 on the low.) I’ve been using a
>variac set at around 90 volts on the mains to drop them down to a safe
>range.  Anybody have a more elegant solution to drop the B+?
>73
>Tim Anderson, AG4XM
>
>
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