If there is power being reflected in the 160/80/40m cases your dummy load is not
presenting a 50-ohms resistive load to the RF output of your transceiver at the given frequencies.
An antenna analyzer would be able to tell you this. This reminds me of a few months ago
when I was testing my transceiver with what I *thought* was a good dummy load.
It turns out I had exceeded the power rating of the dummy load and damaged it (should
have smelled it but I had a head cold so couldn't detect it ;-)).
In that case however all bands were affected. You may have a different situation here.
And I don't know what a *heath antenna* is, It sure sounds like it's an antenna and not
a dummy load which would explain what you are seeing. Dummy loads offer a purely (or almost
purely) resistive (real ) component of impedance to your radio depending on the frequency. The idea
is they allow you to dissipate 100% of the RF energy into it -safely- so you can measure it, tune your AMP/Radio
safely etc. etc. Dummy loads come in various types mainly depending on the amount of power they can
dissipate. I doubt your radio is the problem though.
From: BASILIE <email@example.com>
Sent: Mon, April 12, 2010 9:00:12 AM
Subject: [IC-7000] Re: IC-7000 50 watts on some bans?????
Have you measured the TX power into a known good dummy load, bypassing the
tuner? It is unlikely this is a problem with the radio.
Yes,i went into a heath cantenna with no tuner inline and I did check the voltage on pin 3 and 4,I am using a VS-70amp Astron.Here is what I found.
100% rf power 20 watts Idle 14.00 volts under load 13.61 volts
50% " " 2 watts " " 13.65 "
100% 48 watts " " 13.37 "
50% 5 watts 13.62 "
100% 50 watts 13.10 "
50% 8 watts 13.45
100% 105 watts 13.29
50% 50 watts 13.05
10 meters 100 watts
100% 100 watts 13.00
50% 50 watts 13.32
I hope this makes sense.
--- In ic7000@yahoogroups. com, "Steve W3AHL" <w3ahl@...> wrote:
[Non-text portions of this message have been removed]