Answering your question: "Can anyone think of a variable in the
triband/tower/8 ft rods/ Astron power supply set up that would cause a
Scout's transmit frequency to jump around widely and wildly ?"
Yes. Most Astron supplies have floating outputs. This means that the
negative output is not connected to the cabinet and is not, therefore,
grounded through the AC power cable. If the rig is hooked to the antenna
and you are relying on the rig's power cable to provide the ground for the
rig, then what you are doing is putting any RF energy picked up by the
antenna and feedline right into the regulator circuitry of the Astron.
If this is the case, then the solution is to ground the negative post of the
Astron to its case and then hook the station ground to the supply AND the
rig.
73, Mike N4NT@chartertn.net
----- Original Message -----
From: "robert k stephens" <bstephens1@mindspring.com>
To: <tentec@contesting.com>
Sent: Monday, October 22, 2001 10:25 PM
Subject: [TenTec] Scout problems
> Thanks everyone
>
> In order to save bandwidth I'll try to respond to everyone with one
message.
>
> I don' think it would be the voltage regulator . I assume the factory
would
> have spotted that when it was on their bench.(thanks)
>
> I have Radio Shack ferrite assemblies on my microphone(s) cords and on the
> coax into the rig. I have also looped the coax into an air core coil
choke.
> This didn't help. I didn't think to put a ferite choke on the power cord.
> I'll give that a try.
>
> I have 3 factory power cords that I use interchangably. I'll try to pay
> attention to which one I'm using to see if the cords make a difference.
>
> I don't have problems with all the bands all the time. This suggests a
> ground problem-sometimes in a given setup the ground might be good for one
> band and not another. However, could it not also be caused by an
> intermittent problem in the plug in modules ? Sometimes I can fix the
> problem by reinserting the module - sometimes that works and sometimes it
> doesn't.
>
> I operate under many different conditions. Sometimes I'm inside/sometimes
> outside, sometimes 2 batteries in parallel sometimes car battery with
> engine running sometimes a power supply. For ground I have used cold water
> pipes, copper rods, metal fences and counterpoises. I have tried 3
> different mics. I have experienced fewer problems when the dipole is up
> high, free and clear with a well regulated power supply and short wide
> ground strap to good ground but I want to emphasize that I have also had
> problems under what I consider to be near perfect conditions.
>
> The "guest" operator position at my club is what I consider to be near
> perfect. The tri band beam is up 45 feet, fed by quality coax. The ground
> strap is 1 inch wide in the shack and it connects to buried 8 ft rods.
The
> power supply is an Astron (30 amp ?) The configuration I used bypassed the
> tuner and went directly to the beam. SWR was under 1.5 to 1
>
> Under this condition the frequency varied widely and wildly during
> transmit. I know from past experience that this means that my audio was
> extremely distorted and difficult to impossible to understand. The
Kenwoods
> hooked up to the same situation worked fine and I did a little casual
> contesting breaking pileups and being heard the first time with ease. It's
> hard for me to not believe that something on the Scout is broken (either
> broken in the rig itself or a fault in the plug in modules). Why would the
> Scout be unusable in the same base station situation that the club's
> Kenwood performs well in ? In case I haven't said this before I used to
> have better results with the rig when I first got it than now. I'd like to
> save my money and keep the Scout.
>
> Can anyone think of a variable in the triband/tower/8 ft rods/ Astron
power
> supply set up that would cause a Scout's transmit frequency to jump around
> widely and wildly ?
>
> tnx
> Bob KB1CIW
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