Another possible source of voltage drop is the connector to the
regulator IC. It is a push-on type that slides onto the pins of the
regulator, which is bolted to the chassis. Since the pins of the LM2940
are tinned, this junction could oxidize. I painted a little Deoxit on
the pins of the LM2940 but a better solution might be to solder the
leads directly to the pins. Anyone who has stability problems with a
Scout might check the connector for looseness or poor contact.
The Scout power cord uses a spring type fuse holder with a glass (AG)
type cartridge fuse. Changing to a blade type in a better holder seems
to be a good idea.
73, Bob WB2VUF
"Dr. Gerald N. Johnson, electrical engineer" wrote:
>
> If the LM2940 is true of all Scouts (its was pin and mounting
> interchangeable with the LM7810 that would guarantee that 12.8 volt
> limit without fuse and connector drop).
>
> 1.1 volt drop through the connector and fuse is unreasonable.
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