[TowerTalk] 40-2CD SWR problem

[Jim Vining]

Hi Dick,

         It sounds like poor element connections to me. Taking the
elements apart and cleaning the joints up and then re-assemble with
a new layer of NoOx should fix it. Spring project I wud think.

                                         Jim  N8JV


At 08:36 PM 2-10-2008, Dick Green WC1M wrote:
>Hi All,
>
>
>
>I have a strange problem with my Cushcraft 40-2CD. The symptoms are:
>
>
>
>- The first time I select the antenna and transmit, say at 50W, the SWR is
>very high -- somewhere between 10:1 and infinite.
>
>- Depending on which radio I use, sometimes if I send a dit at about 100W,
>the SWR returns to normal, about 1.5:1.
>
>- The reason it depends on the radio is that one (FT-1000D) folds back power
>dramatically when SWR is high, while the other (Orion) doesn't. Usually have
>to use the Orion.
>
>- Sometimes even 100W isn't enough, and I have to transmit at slightly
>higher power with a linear to clear the high SWR -- perhaps up to 200W or
>so.
>
>- I use an Acom 2000A amp, and it never trips due to the high SWR during
>this procedure, presumably because the reflected power is relatively low at
>100W-200W.
>
>- If I keep transmitting, the SWR stays low.
>
>- After 20-30 minutes of inactivity, high SWR returns. If I give it a shot