CB Radio Wiring Question

[Jerry Bransford]

Everything looks correct in your post Tigerman, especially where you confirm the top of the antenna mount has no continuity to ground but the bottom of the mount shows good continuity to ground. My guess on being able to get a good low SWR with the K40 but not the Wilson is perhaps you're making too big of an antenna length adjustment on the Wilson between SWR checks. In other words you might be missing the Wilson's sudden dip to a good low SWR measurement by missing it with too big of an antenna length change between SWR checks. Sometimes the adjustment difference between a high SWR and the sudden dip in SWR to the desired low level is just a small amount.

 

[Kent Dakin]

keep your power wire OUT of the engine compartment ..that's where your IF is coming from I run the same setup as you but power from fuse box behind glove box.....this coming from a Extra class ham operator of 50yrs. ....take care...N5MCZ

 

[Jerry Bransford]

keep your power wire OUT of the engine compartment ..that's where your IF is coming from I run the same setup as you but power from fuse box behind glove box.....this coming from a Extra class ham operator of 50yrs. ....take care...N5MCZ

Funny how experienced opinions can vary even on the basics. Most, me included, always caution to pick up a 2-way radio's DC power as close to the battery as possible. The fuse box is more likely to have electrically noisy circuits than the battery or Power Distribution Center input power lug will. I built my first ham gear in the early 60's and aside from 3-4 years in non-tech I never left the tech end of the electronics industry.

 

[Kent Dakin]

Funny how experienced opinions can vary even on the basics. Most, me included, always caution to pick up a 2-way radio's DC power as close to the battery as possible. The fuse box is more likely to have electrically noisy circuits than the battery or Power Distribution Center input power lug will. I built my first ham gear in the early 60's and aside from 3-4 years in non-tech I never left the tech end of the electronics industry.

the Alt.., plug wires, fuel inj. & plugs cause the noise.....mine has none .....don't know what field you were/are in but we learned that in basics as RTO operators in the 60's....just trying to help but since you know it all have a nice night

 

[Tigerman]

Jeeps are electrically noisy. It is not unusual to get some interference, which may be coming from the spark plugs, injectors, alternator or any number of sources. Some have reported success in reducing the noise with a braided copper sleeve around the power lead as a shield.

I have a Uniden Pro520XL in my jeep, wired directly to the battery. I get some electrical noise with the engine running which is substantially reduced as to be almost imperceptible by using the ANL switch. What little remains is totally eliminated by turning up the squelch "just a tad."

Thank you for that advice Mr. Bills,

I stripped a TV antenna cable and used the braided copper wire over the positive like you suggested. The noise is reduced. Like you described, with the ANL on, I cannot hear it anymore.

Thanks

 

[Tigerman]

Funny how experienced opinions can vary even on the basics. Most, me included, always caution to pick up a 2-way radio's DC power as close to the battery as possible. The fuse box is more likely to have electrically noisy circuits than the battery or Power Distribution Center input power lug will. I built my first ham gear in the early 60's and aside from 3-4 years in non-tech I never left the tech end of the electronics industry.

the Alt.., plug wires, fuel inj. & plugs cause the noise.....mine has none .....don't know what field you were/are in but we learned that in basics as RTO operators in the 60's....just trying to help but since you know it all have a nice night

I must admit, before I wired the unit to the battery, I stumbled across an auxiliary power wire behind the glove compartment. I got lazy and wired the unit to that line first. After driving around for a bit I got frustrated with the noise and interference and took the time to wire it to the battery. It definitely got less noisy.

I don't mean to disagree with either of you gentlemen, you have vast experience and I do not, but the simple experiment (I do admit a bit subjective, based on my hearing memory and perception) and also the fact that the Uniden's manual specifically said to wire to the battery if possible, makes me think that at least in the TJ's case, it was the better choice.

Jerry,
The Wilson's channel one, with the whip installed at its minimum height is at 2.4 and channel 40 is at 2.8. With the whip completely removed, I have 2.5 or close to it on both channels. Is there any other way to adjust it? At this point the K40 works fine, so I am inclined to just return the Wilson.

 

[Michael D Heit]

Hello,
Did you still through the firewall? I need to run power from the battery direct but cannot find an opening in my 1999 TJ

 

[Michael D Heit]

Argggg.... Drill

 

[Dave Carpenter]

Your setup is similiar to mine. I use the teraflex antenna mount, but on the passenger side. The cable runs under the rear hatch seal, under the carpeting, and up to where the CB is mounted on top of the dash in the corner (rugged ridge mount). I have a 4 ft firestick on the same rigid mount. It doesn't flex much, and I don't think I've ever heard it hit the hard top. I have the Uniden 520XL, which has the ANL switch. Flip it on, and the noise goes away.

The other way would be to put a noise filter on the power leads. I used to get them from Radio Shack, but as we all know, they went bye-bye. Maybe check around at truck stops... they might have one in their accessories.

 

[Michael D Heit]

I want to install a power works 40 amp distribution block and put in my Icom 7000 radio. Also the AH4 antenna tuner for the HF, and a 2 meter mag mount for the VHF/UHF side. You mention tapping off the passenger side for power, which power block could I use to get a 40 amp power line. My jeep wiring diagram shows a max 30 amp block.

I plan to use a long 110 inch whip antenna for NVIS type emmissions.

HF transmit on the IC7000 can be up to 30 amps. Vhf/uh much less. I do a lot of digital so I only run 5 to 15 watts TV in HF mode so much less amps draw. Vhf / uh I keep it down to less than 50 watts and usually 5 watts into the local repeater net.
Also do limited CW but not while driving ...

Thanks for your post and any reply you may send. Mike AD7VV

 

[Jerry Bransford]

Hello,
Did you still through the firewall? I need to run power from the battery direct but cannot find an opening in my 1999 TJ

If you have an automatic, you can pass the power lead through the firewall hole the clutch pedal rod would have passed through, up near the master brake cylinder. If you have a manual transmission, there's a hole with a rubber plug in it just above and to the right of the accelerator pedal. Don't remove the plug, just drill a small hole in it and pass the wiring through.

I want to install a power works 40 amp distribution block and put in my Icom 7000 radio. Also the AH4 antenna tuner for the HF, and a 2 meter mag mount for the VHF/UHF side. You mention tapping off the passenger side for power, which power block could I use to get a 40 amp power line. My jeep wiring diagram shows a max 30 amp block.

I plan to use a long 110 inch whip antenna for NVIS type emmissions.

Connect that level of fuse block directly to the battery connector. But for that, I'd replace the OE battery connector with a more suitable aftermarket battery connector that is connected to the battery cable by being swaged onto it. A 10 gauge wire would be adequate, an 8 gauge would be even better.

 

[Michael D Heit]

Thank you Jerry, I'll look for the point you mention, my TJ is a manual 5 speed so the opening by the master brake cylinder would be the spot I could use. I have the original wiring from Icom for my radio, and plan to use that as my power line. That would then feed the distribution block. The battery mod you mention sounds like a very good idea and as I recall an earlier thread in this debate had a link to one on Amazon or Ebay .. either way I will use that.

Mike AD7VV

 

[Jerry Bransford]

Thank you Jerry, I'll look for the point you mention, my TJ is a manual 5 speed so the opening by the master brake cylinder would be the spot I could use.

No, I said that spot is used by the clutch pedal's rod that goes to the clutch system master cylinder. Since you have a manual transmission that would use that hole, you would need to run your wiring through the hole just above and to the right of where the automatic's shifter cable would have run through. Drill a small hole through its rubber plug, just large enough for the wiring to pass through tightly.

 

[Bill Clark]

I am putting my Kenwood in for 2 M / 70 cm. But another reason I am using the on battery fuse block and Anderson Power Pole connectors is if I buy a replacement for my ICOM 7000 that I use at my desk. If I do I want to
Be able to move the 7000 out and increase the fuse in the block. All of the wiring will handle the increase. WB7NPE


Sent from my iPhone using Tapatalk

 

[Grote]

I haven't seen any pictures of drilling holes in the TJ firewall to run power and antenna cable for a CB or Ham radio. I wanted to keep my power wires as short as possible. Running accross the firewall to the drivers side from the battery added about 5 FT to the run so I drilled holes in the firewall behind the battery instead. I only needed one hole but drilled an extra one while I was at it. I used a rubber weather proofing seal from a surveillance camera as that's what I had on hand. Now the wire run is short enough that I don't have to worrry about voltage drop on a Ham radio.

 

[Jerry Bransford]

Run a slightly larger gauge of wiring and voltage drop for that length of run isn't an issue for your ham or CB radios.

 

[fuse]

I haven't seen any pictures of drilling holes in the TJ firewall to run power and antenna cable for a CB or Ham radio. I wanted to keep my power wires as short as possible. Running accross the firewall to the drivers side from the battery added about 5 FT to the run so I drilled holes in the firewall behind the battery instead. I only needed one hole but drilled an extra one while I was at it. I used a rubber weather proofing seal from a surveillance camera as that's what I had on hand. Now the wire run is short enough that I don't have to worrry about voltage drop on a Ham radio.

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Nice job! I drilled through the same spot for the wiring just because it was convenient.

 

[qslim]

Nice job! I drilled through the same spot for the wiring just because it was convenient.

I did the same, found it to be much easier. That way it comes in right behind the glovebox which can be popped off and it's all right there, you don't have to contort yourself up in the driver well. I don't do great work upside down.

 

[Ray]

I'm with you Jerry,use 10 and 8ga wire on all my radio gear.AG5OU

 

[Grote]

Thanks for all the input. I ran AWG 10 and it's about 18 FT for power round trip to the mounting location above the rearview mirror. The planned radio is a Kenwood TM-V71a. Needs about 13 amps max. Right or wrong, better or worse, it's just what I did.....

KK4EJH