KL7RA wrote:
> Hi Phil
>
> >A good point was made today re the Dow-Key relays
> >found in Harris equipment et al
>
> The failure mode for the Dow-Key antenna relay in my
> RF-103 was caused by using a modern transceiver that
> burned the gold contacts when the 12 Ms close time was
> finally reached.
>
> I also repaired a friends 103 where the contacts were
> completely destroyed. It was driven by a TS-440 and SSB
> only.
>
> But you are exactly correct about moisture. Dow-key relays
> in stack phasing boxes on towers are awful. That idea only
> lasted one season.
>
> 73 Rich KL7RA
>
Just about every Dow Key relay I come across I find that the receive
side of the relay goes bad. Those are the ones that have the movable
contact on the receive side that is supposed to short out the receive
line. They get dirty and won't make good contact on receive. There is no
way to clean inside the contact. I end up removing the whole thing and
replacing it with a transmit side from another relay that is non
shorting. The only way to get a good reliable relay.
73
Gary K4FMX
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