Switching DIODES!
> On May 15, 2016, at 8:04 PM, Gary J FollettDukes HiFi <dukeshifi@comcast.net>
> wrote:
>
> I tried searching before asking the reflector for a solution to this issue,
> no luck, so, here goes…
>
> I have a Scout that works perfectly up through 30 meters.
>
> Above 30 meters, the TX power drops a LOT after a few seconds transmitting.
>
> I know why it does so. The two diodes D3 and D4 on theLLD/ALC board get very
> hot and allow TX power to leak through. This causes a pullback in output
> power as the perceived impedance of the load drops.
>
> If I lift one of the switching diodes, D3, everything is fine, full output as
> long as I want to stay keyed, even on 10 meters. Of course, there is no
> receive as D3 is the receive signal path from the antenna.
>
> My question is, does anyone know why Ten Tec chose to use 1N3007 diodes here?
> This would seem to be a poor choice as these are not particularly fast diodes.
>
> Has anyone tried PIN diodes here? If so, what type was successful?
>
> I guess I could select some but would rather benefit from others' successes.
>
> Gary
>
> W0DVN
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