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9' of coax in mobile install to lower SWR?

just my 2 cents worth here,, i was taught years ago that if you have to change the length of coax to get swr good,, the antenna has a issue with grounding or resonance is not right,,,
 
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just my 2 cents worth here,, i was taught years ago that if you have to change the length of coax to get swr good,, the antenna has a issue with grounding or resonance is not right,,,

Ordered 12' or RG8X with ends on it from the same guy I get a lot of my jumpers from.

Be able to test later in week.

Currently dealing with parasitic draw to the tune of:

1F813314-9173-47D1-9424-98BDF9B7B52E.jpeg

Supposed to be no more than 50milliampres
 
I know people who tune their coax with the MFJ antennalyzer. Does this really do anything? I gather not, judging by the previous responses.

If you tune the coax for an ELECTRICAL halfwave then whatever the impedance is at the feedpoint will be reflected at the other end of that half wavelength of cable. I have 1/2 wavelengths of cables made up for each one of the ham bands so that I can raise my antenna up and check the actual impedance,not the SWR,and then I can determine easier what needs to be done to tune them for 50 ohms. It's a lot better than seeing the SWR go way up as you raise the antenna from a few feet off the ground or due to errors caused by weird impedance and cable effect. An SWR of 2:1 does not tell me if the impedance is 100 ohms or 25 ohms.
 
Ordered 12' or RG8X with ends on it from the same guy I get a lot of my jumpers from.

Be able to test later in week.

Currently dealing with parasitic draw to the tune of:

View attachment 38309

Supposed to be no more than 50milliampres

How is the Alternator doing?

High mileage = time for a brush/commutator and Diode Trio looky-into-see...

Easiest way to check that is to see if the Battery has fuses for the various sections...

Start pulling the fuses at that fuse bank at the battery if it is more convenient - this way you can at least find the guilty branch off circuit causing this draw.

IF it's an older vehicle - see if you can get at the alternator and pull off the main wire (CAREFULLY - prevent arcs - it's live from the battery post) and if the draw is gone, the alternator needs to be replaced or rebuilt.
 
Apparently the A/C relay fuse (and other things on the circuit seems to be it. Dropped from 3.24 amps to 0.11 after I got to that fuse. So I left that fuse out. Will check in morning and see where the voltage is at.

The irony is I noticed my A/C wouldn't take a charge and was showing like 60psi on the low side port (on the guage) just a day ago. So I think my compressor is electrically shot.

I will check the related relay tomorrow at work by swapping it maybe. Or Thursday when I'm off.

Also planning on pulling some more fuse at work tomorrow at lunch and try to get to the magical 50 milliampere as recommended by Ford for this vehicle.
 
Wow...

Yeah, A/C going out while in the "Dog Days" of summer - bummer.

Glad to know you found the circuit. Hope it's just the relay that handles the loading is fried, that you can check pretty easy too. Usually you can swap with another relay to even see if the clutch will work.- I read that in my own manual for my car not too long ago.

Good luck, keep cool!
 
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Wow...

Yeah, A/C going out while in the "Dog Days" of summer - bummer.

Glad to know you found the circuit. Hope it's just the relay that handles the loading is fried, that you can check pretty easy too. Usually you can swap with another relay to even see if the clutch will work.- I read that in my own manual for my car not too long ago.

Good luck, keep cool!


4 windows. All good. Like the 70-80's. No AC in my car then either. Just go faster.
 
All you need is enough cable from radio to antenna. Do you plan to run an amplifier ?

RG-58 cable is recommended for mobile because it has solid dielectric inside, suitable for sharp bends. You can use RG-8X but must avoid sharp bending because it has foam dielectric.
 
I wish I had my old "Yellow" car...

No, it wasn't yellow as in paint job...

Yellowed from age...but Oh boy! ouch! ... those memories...
 

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