[sdiy] Module power - regulated or filtered (passively)?

[KA4HJH]

> On Jan 18, 2020, at 5:59 AM, Neil Johnson <neil.johnson71 at gmail.com> wrote:
> 
> Brian wrote:
>> Personally, I would not assume that a series resistor was intended as “protection.”
> 
> Indeed not, unless you're using fusible resistors.

When I worked on cable TV amplifiers/power supplies there was a model made by Amico that used two 4.7Ω 1/4W resistors in this fashion. Naturally all of the units sent in for repair had one or both resistors fried. Why they even bothered to use them was a mystery to everyone as at least one transistor in the PS would invariably be toast as well. The icing on the cake was that it was necessary to shotgun all three transistors in the PS because replacing one would fry another on the next power-up. This went in endless circles. Brilliant piece of design. A model for us all.

So you see kids, when it comes to shotgunning there ARE times when it's Standard Operating Procedure.


Terry Bowman, KA4HJH
"The Mac Doctor"

https://www.astarcloseup.com/

“The book said something astonishing, a very big thought.
It said that the stars were suns, only very far away.
The Sun was a star, but close up.”—Carl Sagan, Cosmos, 1980


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