I understand what you're saying, but everything was working fine,
for several years, and now it's not. The rig, the feed line, and the
antenna - a 10 meter dipole - have not changed in obvious physical
condition.
The last time that this happened, I took the rig into a repair shop.
I was told that it, "was just some carbon build-up on the relay." I
don't know if this was the cause, but the bill didn't add up to much, so
I assumed that this was the case. I felt a little stupid for not
considering something this obvious (always check the simple things
first, right?), but I just packed it away as one of life's little lessons.
I checked the relay on the tuner and sprayed it with some contact
cleaner, but the problem still exists. I "should" be able to fix this. I
think that I'm just overlooking something...but what?
I thank you for your response.
Charlie Shaw
KB3BTO
Reg Edwards wrote:
Try giving the auto-tuner a little external assistance.
Connect a few micro-henrys or a capacitor in series or in parallel with the
transmission line at the antenna end of the tuner. This will often shift
the line input impedance into a range which the auto-tuner can accommodate.
Or try changing the length of the line by a few feet.
If the line input impedance is measured it can be deduced what sort of
additional component is needed for one awkward band. It may not adversely
affect other bands.
In the worst case situation you can always prune the antenna. Never give
up.
----
Reg, G4FGQ
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