Cannot get my cb radio tuned

[kolelt]

Ready to just drive this truck into a tree. Nothing ever works. Installed a cobra 19 DX IV with 18' firestik cable and firestik tunable antenna. Got a ASTATIC PDC1 SWR METER. I followed this video. https://www.rightchannelradios.com/blogs/installation-guides/18330687-cb-antenna-tuning-instructions

And for the love of god. I cannot get it tuned. I set my meter on FWD and turn the nob to SET ( the read area ) then when I switch to REF it stays the same basically. Doesn't even drop a hair. Not even close to how it is in the video. I grinded the paint down on the cb mount, and all. Any idea what's going ? These are brand new items.

 

[Airmapper]

CBs are crap. Nobody who knows radio wants one. We just use them because it's the going form of comms.

Things that might help us to know:

Where have you mounted it.

How long is the antenna.

What kind of grounding setup do you have, you may have gotten the antenna grounded to the mount, is the mount grounded to the vehicle?

There are a bunch of possible reasons why it's not working. That is why I hate CB's.

 

[Unner]

Ready to just drive this truck into a tree. Nothing ever works. Installed a cobra 19 DX IV with 18' firestik cable and firestik tunable antenna. Got a ASTATIC PDC1 SWR METER. I followed this video. https://www.rightchannelradios.com/blogs/installation-guides/18330687-cb-antenna-tuning-instructions

And for the love of god. I cannot get it tuned. I set my meter on FWD and turn the nob to SET ( the read area ) then when I switch to REF it stays the same basically. Doesn't even drop a hair. Not even close to how it is in the video. I grinded the paint down on the cb mount, and all. Any idea what's going ? These are brand new items.

I ordered the same exact SWR meter and it was defective out of the box. Might want to check that out too, it drove me crazy until I realized it wasn't any of my CB equipment, but the SWR meter instead.

 

[Frdmskr]

Antenna problems mean the mounting is bad. Check for a short in the cable using a simple Volt Ohm Meter for a start.

Tell us more about the mount.


Sent from my iPhone using Tapatalk

 

[kolelt]

I ordered the same exact SWR meter and it was defective out of the box. Might want to check that out too, it drove me crazy until I realized it wasn't any of my CB equipment, but the SWR meter instead.

hmmm thanks ill try ordering a new one or different one. Did you order a new one or a different one?

here is my set up.

 

[frodiesel]

Do you understand the concept of a ground plane? (If not see below) Thats not how radio works. I am sure other people have gotten those side brackets to work but i doubt you are creating an effective ground plane.

If no ground (plane) how will the radio effectively output power? A magnetic mount that you only deploy when trailing would be largly more effective than what you're working with in that pic.

 

[Dezert4Runner]

hmmm thanks ill try ordering a new one or different one. Did you order a new one or a different one?

here is my set up.

This may be a dumb question, but did you check to make sure the fire ring coax has the lip facing up towards the mount? If it was reversed (pointing down) it would cause the coax to not be grounded.

 

[DK327]

OP, have you tried tuning the antenna to see if you get a different reading? Also since the antenna is going to the SWR meter, you have another cable going from SWR meter to the radio right? What is the length of that cable? If it's too short, try a longer length cable and check SWR again. Also, when checking SWR, make sure all doors of vehicle are closed and the vehicle is in a parking lot with no nearby obstructions or in a field with no trees near by. All these objects reflect the signal and can cause a false SWR reading.

 

[kolelt]

I noticed in the instructions that the fire cable has one side that has more of the plastic washer showing. And it said to have that side against the plate. Basically a small gap. So how would that ground it ? Right? I had this thing pretty tight so know that fiber washer built into the fire cable is basically flat.

Should I try running a small wire from the bolt that screws everything in to chassis?

Yes I tried tuning the antenna. Nothing.

If I unplug the antenna from the SWR METER. It does the same. Basically push down on the microphone and I set the handle to set (red area). Holding the button I switch to REF and it's the same. Nothing changes.

 

[DK327]

If I unplug the antenna from the SWR METER. It does the same. Basically push down on the microphone and I set the handle to set (red area). Holding the button I switch to REF and it's the same. Nothing changes.

I hope I'm misunderstanding the above quote but it sounded to me like you're disconnecting the antenna from SWR meter and then keying up the microphone??? Because that would not be good... :wow2:

 

[kolelt]

I hope I'm misunderstanding the above quote but it sounded to me like you're disconnecting the antenna from SWR meter and then keying up the microphone??? Because that would not be good... :wow2:

I was seeing if the readings were the same or different. I doubt it will hurt anything in a second.

 

[Dezert4Runner]

I noticed in the instructions that the fire cable has one side that has more of the plastic washer showing. And it said to have that side against the plate. Basically a small gap. So how would that ground it ? Right? I had this thing pretty tight so know that fiber washer built into the fire cable is basically flat.

Correct, the plastic washer that's built into the fire ring coax should be faced up against the bracket. The bolt head on the under side should be flush against the side of the fire ring coax with the metal ring, not the plastic spacer. This is what mine looks like (sorry, it's dark when I took this just now).

 

[DK327]

I was seeing if the readings were the same or different. I doubt it will hurt anything in a second.

I would try a different CB radio and highly recommend NOT transmitting without an antenna connected, not even for a second. If the second radio does the same thing it might be a grounding issue or maybe a defective antenna. Try a Wilson Little Wil magnet mount antenna which will give you better performance, IMO.

 

[kolelt]

I would try a different CB radio and highly recommend NOT transmitting without an antenna connected, not even for a second. If the second radio does the same thing it might be a grounding issue or maybe a defective antenna. Try a Wilson Little Wil magnet mount antenna which will give you better performance, IMO.

Don't really want to spend money on new cb radio, or antenna. They are new.

Could be a bad SWR METER. or just a bad ground or no ground. I'll need to check the ground. And maybe order a new SWR METER. Any recommendations for a SWR meter ?

 

[DK327]

Don't really want to spend money on new cb radio, or antenna. They are new.

Could be a bad SWR METER. or just a bad ground or no ground. I'll need to check the ground. And maybe order a new SWR METER. Any recommendations for a SWR meter ?

I understand your frustration but SWR meter is probably working fine if you're keying up and the needle is actually moving around when you turn the knob. I mean it's possible that it's bad but not likely, IMO. Bad ground or no ground is a possibility but why not test the current antenna setup with another CB radio? Not saying buy one, just go to a CB shop at a truck stop and have them test it using their radio, then have them test YOUR radio to see if it's functioning correctly with their setup. The SWR meter you have now is same one I have and it's fine, I've since bought another one that tests up to 100W but it's the same brand. I wouldn't spend money on a more expensive SWR meter, personally.

If your radio is bad, I have my old radio (Cobra 18 WX ST II) laying around, if you promise to not transmit with it without an antenna attached, ever again!

 

[Unner]

I ended up ordering a different one. I got a slightly more expensive one, but still less than $20 I think.

 

[kolelt]

I ended up ordering a different one. I got a slightly more expensive one, but still less than $20 I think.

Brand ? Please

 

[wcjeep]

For testing purposes, don't be afraid to remove the spring to verify SWR. Did you have any extra pieces when you were done? It seems like you are missing a nylon washer on the bottom side of the antenna mount.


Some combo's have a difficult time with SWR. The old school magnet mount antenna with integrated cable usually works perfect. It does scratch the paint.

 

[Kanoe]

Let's assume for a minute that your meter is working and being used correctly.

Something that will give you the same reading in both the forward and reverse direction is a dead short somewhere between the meter and the antenna. A short between the centre conductor and the outer braid that is. Possibly in the premade coax or in the antenna mount/base itself. Also a break (open) in the centre conductor MAY show the same thing, full reflection, but I am not positive about this.

Just something you can check easily. Use your DVM and verify no shorts (centre to braid) with the antenna removed. And verify continuity on the centre conductor end to end. Some antennas will measure a DC short with the DVM, while others do not. I am not familiar with CB as we use VHF in Canada mostly. That is why I suggest you remove the antenna before testing. Lastly verify you have proper contact between the antenna and the coax, however that is made in your setup.

Good luck.

 

[mckennar]

Make sure the underside of your drifter mount where it contacts the cable is bare metal. Also make sure where the drifter mount interfaces with the vehicle body is bare metal as well. Check continuity between the mount and the - terminal on the battery.

Also ensure that the center barrel / stud of your antenna as it goes through the drifter mount isn't shorting on the mount itself. It needs to be perfectly centered in the hole and insulated either via airgap or nylon washer from the mount.

Mine would not stay centered, so I hogged the hole out to 1/2" ID and bought a nylon washer with a deeper "barrel" on it. This prevented the center stud for the antenna from contacting and grounding out on the mount. Not sure about how your cable works, but on mine (a more traditional setup with a mounting stud on the underside of the mount instead of the firestik cable you're using) this helped a great deal.

FYI I'm also using a drifter mount and in addition to scraping away the paint/rust proofing I sprayed on there, I just bought a $5 braded ground strap with 1/2" eyelets and slipped it around the outside of the nylon washer's barrel and sandwiched it between the drifter mount and the antenna stud (on the underside of the mount). I connected the other end to the frame. My SWRs are ~1 and I get ~5 miles of Rx/Tx on a 4' Firestik. Before good ground plane my SWRs were 4+ and I had almost no Tx and very short range Rx with lots of interference.

Good luck. I can get pictures if this is as confusing to read as it was to type. And disclaimer, I don't know much about the type of cable you're using - my setup is using a traditional cable with a traditional stud mount.

EDIT: Here's a (garbage) image. Disregard the ugly, this isn't the final form, but it works for now. I don't like the exposed threads and potential for water intrusion into the threads... hoping my coax-seal gets here before the rain does.