Scott MacKenzie wrote:
> All:
>
> I have a 6M beam that is showing high SWR (10:1). I checked each connector
> to the antenna by disconnecting and placing a dummy load. Finally up at the
> antenna, I disconnected the antenna, and placed the dummy load as the
> antenna. Readings were 1:1 SWR. I then clean up the connector at the
> antenna, and retest. SWR is still high.
>
> I then pull down the antenna (K1FO or similar - not M2) and check it out.
>
> With the coax disconnected, I check the connector - good continuity from the
> center pin to the otherside of the connector (where the gamma match is
> attached.
>
Ian already had some good comments on this.
In addition, make sure the center pin is ALL the way in. It's possible
to assemble a connector and not get the center pin fully forward.
>
> I check from center pin to ground on the conductor to see if shorted -
> Circuit is open.
>
> I check to make sure I have continuity between outside of gamma and rest of
> antenna. Circuit is fine - and shows continuity.
>
>
I thought the DS50-4 used a T-match?
If using a sleeve balun and it's properly connected to the braid, how is
the braid waterproofed?
If the sleeve is either clamped or soldered to the braid it needs to be
thoroughly moisture proofed. Although as hams we tend to use a lot of
RTV and I too use a lot of Silastic RTV (TM) it is water proof, not
moisture proof. However for an open sleeve it shouldn't make a
difference, BUT it is very difficult to waterproof braid with any of the
RTVs as they are so thick it makes thourough penetration of the braid
difficult. Something with a much lower viscosity such as "Liquid
Electrical Tape" would be a better choice and is available at most
hardware stores. It's also available in several colors. As it's in the
open there is little need to worry about which RTV is used.
> The only thing I can think of left is to replace the coax less shield inside
> the gamma.
>
> What else can it be?
>
> I was hoping to get this up higher in the air for the summer Es season.
>
> Thanks
>
> Scott
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