Need a refresher on coax

[Gunner357]

Im using a Galaxy 88 with a xforce 350 with a preditor 10k on a custom 3 magnet mount that was made by a guy at Cowtown CB years ago I havent used the mag mount in while so first question do I put the two mags that are together in front?? second question is the coax Im using rg8 from the antenna to amp then from amp to radio using rg8mini is the ok ? BTW I hooked radio up real fast and threw the antenna up and got a 1:3 on 1 and 1:4 on 40 ..... i have more question on the p10k but ill head to antenna help on those thank you

[jessejamesdallas]

Have two magnets facing towards the front, and one facing back...You want more magnet in front so if you tag a tree limb you have more magnet holding down the fort...

As for the RG8 and mini8 stuff go's, that's fine...I have RG 213 at the house going from my amp to the antenna, then mini 8 from the radio to the amp and meter...as long as everything's 50 ohm your good to go...

As for the 10K...not sure which one you have, or which lower shaft you have, but some Predators 1.3 to 1.4 maybe as good as you can get unless you move the antenna to a different location on the roof (assuming you have it on the roof, since you said your using a tri-mag mount)

Sometimes placing the antenna farther back on the roof, will let the antenna tune lower, vs dead center on the roof...(I ran into this on my Suburban...antenna tuned better towards the back of the roof)

Sometimes with the Predators, the shorter shafts like 12" and 9" won't tune that low on roofs, where the 17" and taller ones will tune lower...(don't recommend the 22 and 27" shaft 10K's for roof mounting...they tune great! But also get broke easy...been there, done that...more than once!)

[Gunner357]

Have two magnets facing towards the front, and one facing back...You want more magnet in front so if you tag a tree limb you have more magnet holding down the fort...

As for the RG8 and mini8 stuff go's, that's fine...I have RG 213 at the house going from my amp to the antenna, then mini 8 from the radio to the amp and meter...as long as everything's 50 ohm your good to go...

As for the 10K...not sure which one you have, or which lower shaft you have, but some Predators 1.3 to 1.4 maybe as good as you can get unless you move the antenna to a different location on the roof (assuming you have it on the roof, since you said your using a tri-mag mount)

Sometimes placing the antenna farther back on the roof, will let the antenna tune lower, vs dead center on the roof...(I ran into this on my Suburban...antenna tuned better towards the back of the roof)

Sometimes with the Predators, the shorter shafts like 12" and 9" won't tune that low on roofs, where the 17" and taller ones will tune lower...(don't recommend the 22 and 27" shaft 10K's for roof mounting...they tune great! But also get broke easy...been there, done that...more than once!)

Thanks for the reply JJD well i had a 17 inch shaft on my other truck tune great and I do have a 27" shaft im using the 17... however its not tuning good now for some reason when I did a test earlier it matched at the above figure now that I ran the rg8 and put the antenna on the roof im getting 1:5 low power 2: hi power now bare in mind Im running no amp at the moment I need to run the wire etc but its so damn hot here I run outa shade trees to park under lol...also Im getting very bad electric noise when I start the truck never had that issue before its so bad I cant hear anyone from a distance,I lost my patience do being too hot and nothing going right I also rewired coax again do to a bad ground Im at a loss now

[jessejamesdallas]

If it's old coax, you maybe wasting your time trying to tune it...Could be connectors bad, or just old coax that has had water inside at one time...As for the engine noise..."welcome back to the world of CB Radio!"

Tracking down engine noise problems is always fun...But since you seem to be having issues already getting SWR where it needs to be, I'm thinking once you fix the SWR tuning problem, some of the noise problem may also go away...9 x out of 10, engine noise comes in threw the antenna...I can only think of one time where I had a noise problem that was actually coming in threw the power wires (which is where most think the noise comes from...sometimes it is, but more times than not noise is picked up through the coax and antenna.)

17" shaft IMO is the best shaft for roof mounts...(what I use), however usually the 27" shaft will tune the lowest...so if you can't get a 27" shaft to tune lower than 1.4 SWR, then you have a coax or ground problem somewhere...should be seeing 1.0 - 1.1 SWR with the 27" shaft on the roof.

[Gunner357]

I had a roll of bulk roll of RG8 and new PL259 connectors I made coax up myself...... I tested the coax there were no shorts...I'm going to start today by grounding that radio to the chassis, my power wires aren't shielded just a 2 conductor red/black covered HD cable and ran threw the Firewall to battery, My coax is run over the roof down the back of cab threw a hole I drilled up to the radio. The Antenna side of the coax does not use a PL259 connector I have a copper lug soldered on and soldered a lug on the shield and grounded it to the mag mount.... I had this mag mount made up by the owner at the time of Cowtown CB the P10K maker......

[Gunner357]

well a no go with adding a strap from radio frame so now its either put the longer 27 inch shaft on or I have another smaller coil my p10k came with originally see if that helps.....and I cant not find any CB supply house anywhere close to me in Michigan anymore......

[MDYoungblood]

Coax even though not used, old coax still deteriorates over time but still should be usable to a point, I make antennas (double bazookas) out of it and the shield for ground straps mostly. The terminal end of your coax you need to make the exposed center short (length), as it will act as part of the radiating element.

When using a magnet mount the ground plane is capacitance and the distance from the roof adds to this measurement, you could move the antenna back and forth to find that "sweet spot".

Last you might be experiencing some CMC (common mode current) causing the SWR meter to give you a false reading. If you adjust the antenna with the amp out of line, get a good reading and the reading goes south when the amp is hooked back up the problem is on amp's side of the connection, possible jumper or the amp.

3's

Greg

[Gunner357]

well there been new developments now......My Galaxy88 when hooked up to the ( Dosy swr meter pm2001ts) low watt setting I cant adjust the calibration on the swr meter. it wont swing to the cal side.... now if i turn on Hi power setting I can calibrate the swr meter and get over 2:1 on ch 20 also now the RF meter isn't working go figure. so 1 of 2 things i determine is going on the low power finals/pots ?? if you will I'm not familiar how that works are shot?? OR when I was running the amp way back I lowered the wattage on the radio to run the amp I don't remember BTW low getting not even showing 1 watt show like 1/2 watt, Hi power was showing 15w.

So I got my dads Galaxy 99 he had when he was a trucker (passed away now) which was modified with all the goodies in power hooked it up messed with the antenna more, raised stinger up 6 inches best I got out of that radio so far is: On low power 8watts ch20 1:6 ch1 1:7 ch40 1:5 On hi power 20watts (ch20) 1:7/1:8 (ch1) 1:9 (ch40) 1:7 ...now I DO NOT HAVE AMP HOOKED UP its all radio....Any Thoughts ? BTW its receiving great....Not sure about TX however......

[Gunner357]

Oh BOY not having any luck....Went out to the truck turned radio on the frequency counter go to 33.**Censored** it varies.... and satys there no matter what channel any hints on that one?? That is with the Galaxy 99v that was working perfect last night I wanna say a BAD word right but.... rules anyway Going to put the Galaxy 88hl in since its working in the house and see if it will work in truck If not Im *^%$%^^$