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W2 Meter Question

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JHRichards

W2 Meter Question

Greetings -

I recently assembled and installed the W-2 SWR/wattmeter.

Background:

I have several antennas. I have an A/B switch to select either a
vertical, or one of several dipoles further selected using a remote coax
switch. The sensor is on the branch with the vertical. I use a linear
amp at 500 watts when net control for a Brand X rig owners' net.

Question/Problem:

When using the vertical, the meter works on the A side of the switch
works properly. But, using any of dipoles, on the B side of the switch,
it goes crazy and all the diodes light up. It only does this when the
amp is on line. I tried re-routing the sensor cable with no advantage.

Any ideas? Thanks in advance.

===================== K8JHR ========================
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Vic Rosenthal

Re: W2 Meter Question

I understand that you have the sensor connected to the vertical
permanently. But when you transmit on one of the other antennas, it
reads a very high SWR, even though out of the circuit.

What it sounds like is that the vertical is picking up RF from the
dipoles. When they are selected, the coax to the vertical is either
shorted or open, depending on the switch. The coax to the vertical is
operating at a high SWR -- it is just being excited by the RF pickup,
not the transmitter.

One solution would be to put the sensor in the line from the transmitter
to the switch rather than from the switch to the vertical.

Vic/K2VCO

On 6/4/2014 8:51 PM, K8JHR wrote:

> Greetings -
>
> I recently assembled and installed the W-2 SWR/wattmeter.
>
>
> Background:
>
> I have several antennas. I have an A/B switch to select either a
> vertical, or one of several dipoles further selected using a remote coax
> switch. The sensor is on the branch with the vertical. I use a linear
> amp at 500 watts when net control for a Brand X rig owners' net.
>
>
> Question/Problem:
>
> When using the vertical, the meter works on the A side of the switch
> works properly. But, using any of dipoles, on the B side of the switch,
> it goes crazy and all the diodes light up. It only does this when the
> amp is on line. I tried re-routing the sensor cable with no advantage.
>
> Any ideas? Thanks in advance.
>

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Don Wilhelm-4

Re: W2 Meter Question

In reply to this post by JHRichards

The wattmeter should be connected between the KPA500 and the KAT500 if
you want to read a low SWR. The SWR that is seen by the KPA500 is the
only thing that matters, and that would normally be 1.5 or less.

Your connection (between the tuner and the antenna) will not change the
SWR reading because you are reading the SWR into the antenna, and the
tuner will not alter that.

The tuner will not change the SWR on the antenna, but it's function is
to transform the antenna feedpoint impedance into something that will be
seen as a low SWR by the transmitter PA stages - it does not change the
SWR of the antenna/feedline itself.

If the SWR varies with the power level, that is usually a result of RF
on the outside of the coax that can only be properly cured by common
mode chokes placed in the antenna system.
See the RFI information presented by Jim Brown K9YC at
http://audiosystemsgroup.com/RFI-Ham.pdf for ways to eliminate common
mode current on the feedline as well as other problems with RFI
suppression in the hamshack.

73,
Don W3FPR

On 6/4/2014 11:51 PM, K8JHR wrote:

> Greetings -
>
> I recently assembled and installed the W-2 SWR/wattmeter.
>
>
> Background:
>
> I have several antennas. I have an A/B switch to select either a
> vertical, or one of several dipoles further selected using a remote
> coax switch. The sensor is on the branch with the vertical. I use a
> linear amp at 500 watts when net control for a Brand X rig owners' net.
>
>
> Question/Problem:
>
> When using the vertical, the meter works on the A side of the switch
> works properly. But, using any of dipoles, on the B side of the
> switch, it goes crazy and all the diodes light up. It only does this
> when the amp is on line. I tried re-routing the sensor cable with no
> advantage.
>
> Any ideas? Thanks in advance.
>

Dake Holloway, K4EQ

K1 Tilt Stand

In reply to this post by JHRichards

Does anyone have a KTS1 tilt stand for the K1 they would like to sell?
If so, please email me directly at: [hidden email]. Thanks.

Dale, K4EQ
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