CB and GMRS Install

[Radio Guy]

I took it as it works "great" for him.... I didn't take it as a disservice. I guess if a branch is going to take out the antenna, its probably going after the mirror too.... From what I've seen, that placement seems to be a very popular...

In your experience, what would you think the range of these ghost "pud" antennas achieve in a moderately wooded area ? Do you think they would suffice in a trail convoy or an open road trip.

I have the MXTA26 whip, but its mounted like @sharpsicle , but on the passenger side. I do not really have a good way to test real world performance and would rather not be testing and be "in the need" at the same time. Any suggestions on testing ?

I like to present facts and I don't have any documented data on the difference in performance between a UHF pud and other UHF antennas at the moment. I have tried them and have noticed the reduction in performance and its not subtle. Most of my use is mobile to repeaters and not much if any simplex use on UHF.

I did pay more attention to the VHF pud antennas where I compared one to a basic 1/4 wave whip noting signal strength from several 2m repeaters and multiple NOAA weather transmitters and there was a very noticeable degradation going from the pud to the whip. Driving around I noticed lots of flutter and dead spots on the pud where the whip was virtually noise free. This was with a roof mount on a different vehicle and both antennas tested on the same mount.

I can say for close range convoy or down the highway up to a few miles line of sight on GMRS a pud antenna mounted below hood level should be heard for the most part. Thick foliage and dense trees attenuate UHF signals so in a hilly area with dense trees there will be a point where the pud antenna will fade out and other types will still be heard. This will also depend on vehicle orientation if the pud antenna is mounted below the hood where the vehicle body will block or attenuate the signal in some directions.

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[SargeDiesel]

I like to present facts and I don't have any documented data on the difference in performance between a UHF pud and other UHF antennas at the moment. I have tried them and have noticed the reduction in performance and its not subtle. Most of my use is mobile to repeaters and not much if any simplex use on UHF.

I did pay more attention to the VHF pud antennas where I compared one to a basic 1/4 wave whip noting signal strength from several 2m repeaters and multiple NOAA weather transmitters and there was a very noticeable degradation going from the pud to the whip. Driving around I noticed lots of flutter and dead spots on the pud where the whip was virtually noise free. This was with a roof mount on a different vehicle and both antennas tested on the same mount.

I can say for close range convoy or down the highway up to a few miles line of sight on GMRS a pud antenna mounted below hood level should be heard for the most part. Thick foliage and dense trees attenuate UHF signals so in a hilly area with dense trees there will be a point where the pud antenna will fade out and other types will still be heard. This will also depend on vehicle orientation if the pud antenna is mounted below the hood where the vehicle body will block or attenuate the signal in some directions.

Thank you. How would one go about without sufisticated equipment (if possible) testing the different between mounting locations. As discussed before, the below the hood, cowl mount vs on the hood lip mount ? I have the Midland ghost and MXTA26 and both mounts.

 

[Radio Guy]

Thank you. How would one go about without sufisticated equipment (if possible) testing the different between mounting locations. As discussed before, the below the hood, cowl mount vs on the hood lip mount ? I have the small pud and a midland MXTA26 and both mounts.

You would need a way to receive GMRS signals and display precise signal levels. A cheap dongle SDR receiver can do that and you set up the receiver a distance from the vehicle, test the level with one antenna then swap to another and so on. Then move the vehicle or the receiver/pickup antenna and test again. A spectrum analyzer is typically used for antenna measurements.

The way I would do it is make or come up with a rotating platter you can park the vehicle on. Then rotate the platter with vehicle at 1RPM while transmitting and taking data on the screen of a spectrum analyzer with pickup antenna about 50ft away in zero span mode with the sweep speed matched to the platter speed. Then swap antennas and repeat. You would have a wiggly line that represents 360 degrees of transmission and you can overlay plots from different antennas to see the gain or loss in any direction.

I will be doing a version of this without rotating the vehicle to simply measure gain between a bunch of different antennas. Many of these antennas will be in the GMRS range so I can post the info in a week or two when I get it.

 

[FKN Slayer]

You guys that mounted radios overhead, is there an easy way to snake the wiring to get it underhood to the battery? I'm assuming on either side of the windshield.

 

[Artsifrtsi]

You guys that mounted radios overhead, is there an easy way to snake the wiring to get it underhood to the battery? I'm assuming on either side of the windshield.

Do you have the AUX switches? There is a constant on lead behind the glove compartment if you have it... then just run the wires behind the windshield frame plastic.

 

[FKN Slayer]

Do you have the AUX switches? There is a constant on lead behind the glove compartment if you have it... then just run the wires behind the windshield frame plastic.

I do have the aux switches. Can you run a 50 watt radio off them, safely? I have a kg1000g. I had it wired direct to the battery when I had my Ram. I was going to do the same with the Gladiator.

 

[Artsifrtsi]

I do have the aux switches. Can you run a 50 watt radio off them, safely? I have a kg1000g. I had it wired direct to the battery when I had my Ram. I was going to do the same with the Gladiator.

I would think so, it's 12 volt, even using the max power of the RF, it should only eat about 4 amps of current. Easiest way to check, is if you have a bench power supply, set to 12v, and crank the current to full... power the radio, and transmit at full power and see what the PS indicates as the current load.

Usually the reason most people are connecting to the battery directly is to avoid noise on the power side.

 

[Radio Guy]

I would think so, it's 12 volt, even using the max power of the RF, it should only eat about 4 amps of current. Easiest way to check, is if you have a bench power supply, set to 12v, and crank the current to full... power the radio, and transmit at full power and see what the PS indicates as the current load.

Usually the reason most people are connecting to the battery directly is to avoid noise on the power side.

A 50 watt UHF radio will draw closer to 8 amps. Maybe a little more but not less.

 

[Artsifrtsi]

A 50 watt UHF radio will draw closer to 8 amps. Maybe a little more but not less.

I was just taking a WAG...

If concerned with noise, could wrap a ferrite into the power lead.

 

[Gvsukids]

Here is an under hood night time pic and its difficult to get a camera up in there. The mount has two set screws that dig into the folded over underside of the hood. It doesn't damage the top side which has a rubber pad and I've probably put on around 200 of these mounts in my time.

Is it okay if I have the hood mount is tilted? It's the Midland version and the tighter I make the Allen head screws, the more the front lifts up off the hood.

 

[Radio Guy]

Is it okay if I have the hood mount is tilted? It's the Midland version and the tighter I make the Allen head screws, the more the front lifts up off the hood.

It should sit flat. I see a gap between the back edge of the hood lip and the inside edge of the mount so try to seat the mount right up against the hood lip. That might tilt the mount down flat or the rubber on the bottom of the mount could be causing a problem and maybe trimming a little off the lip side will lay it down.

 

[Gvsukids]

It should sit flat. I see a gap between the back edge of the hood lip and the inside edge of the mount so try to seat the mount right up against the hood lip. That might tilt the mount down flat or the rubber on the bottom of the mount could be causing a problem and maybe trimming a little off the lip side will lay it down.

As a tighten the Allen screws, the mount slides towards the rear of the hood; causing the gap

 

[Radio Guy]

As a tighten the Allen screws, the mount slides towards the rear of the hood; causing the gap

Hmm, I’ve never used a Midland mount and usually go for Laird or Larsen or Maxrad. It could be the set screws on those sit further back on the bottom ridge. Check out my post #10 in this thread showing my current Laird mount I got off eBay for about $20. It sits very flat.

 

[donmontalvo]

Fast forward a few years…

https://donmontalvo.com/2023/06/20/ham-gmrs-and-cb-relocation/

 

[Glad Jeeper]

You guys that mounted radios overhead, is there an easy way to snake the wiring to get it underhood to the battery? I'm assuming on either side of the windshield.

Look at my post dated Mar 27, 2022 I ran the power wire direct to battery. Easy to run behind the pillar trim, there is a channel that the power cords fits perfectly.

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