Off Roading

[gortex2]

Dixie Run at Windrock this weekend if anyone is looking for something to do. We have repairs from Uhwarrier JJ last weekend so can't make it to this one. Fun weekend in Uhwarrie again even with a little breakage..litterly lost the brake line on left rear (steel line near frame) on Dicki Bell and limped to Troy for parts. Then the other half backed into a tree on sunday and we broke a ujoint. Pile of parts at home so busy weekend. next trip is Cumberlands in October. 

 

[nokones]

About a month or two ago, there was a discussion on that the CB Radio FM Mode may be something that should be looked at to consider bringing back the use of the CB radio for uses such as Off-Road Trail Comms.  I stated that the CB FM Mode would probably propagate or provide better communications than the CB with AM modulation, and even better than FRS.

Some Forum members disagreed but no one could cite any facts or back up their statements.  I related that I think the CB FM modulation would have a better signal-to-noise ratio thus, better communication Farz.

I also stated that as time permits, I would conduct a radio comparison test.  Well, that day came, and I conducted the subject test comparing the communications with FRS, CB AM, and CB FM.  I kept the test simple, and I did not record any RSSI (Radio Signal Strength Indicator) readings.  I just did the ol’ hoot & howler type test to see if you can hear the communication and determine the usable distance and audio quality between the three subject radio transmissions.

The test was conducted essentially in a desert environment on flat terrain, with a slight dip in elevation for a dry creek bed and a test point was conducted in that dip, consisting a few cacti, pucker bushes, and giggly weeds, with no other obstacles.

A 2007 Chevrolet Avalanche was the Stationary Transmitting Point using a Cobra 29 LTD Classic Nightwatch AM/FM CB Radio with a Firestik II 4 Ft. Antenna in the center of the roof.  CB Ch. 16 was used for both the AM & FM modes and the antenna was tuned at less than 1.1:1 VSWR.  The CB Radio operated in the AM Mode with a Dead Carrier, no modulation, at 3.5 RF watts and was drawing 14.01 DC volts at 1.12 amps; and 3.9 RF watts with modulation, at 14.00 DC Volts and was drawing 1.46 amps.  In FM mode, the radio was emitting 3.7 RF watts with essentially no difference in power draw.

The data collection vehicle was a 2023 Jeep Wrangler Rubicon using a Cobra 25 LTD Classic CB AM/FM radio with a Firestik II 5 Ft. Antenna tuned to less than 1.1:1 VSWR and the antenna located on the rear Spare Tire Carrier Bracket near the passenger side of the vehicle.

The data collection consisted of collecting test data every ¼ mile driving away from the stationary vehicle.  The test concluded at the 3.25 mile checkpoint.  The data collection vehicle operated the radio squelch level at the threshold of squelching out the noise.

The FRS radios were two Midland LXT radios with fully charged batteries.  The stationary vehicle transmitted on the FRS radio from inside the vehicle as a user would be doing on an actual off-road trail run and the test collection vehicle was receiving the communication transmission from inside the vehicle as an user would be doing on an off-road trail run.

The RF output power was not checked due to the inability to measure.

The FRS became non-existent passed the ¾ mile mark.

The CB AM signal was good and quiet up to the 1 mile mark.  The next ½ mile, the signal was readable but RF noisy.  At the 2 & 2 ¼ mile marks the signal was barely readable.  At the 2 ½ mile mark the signal was non-existent and covered by possible skip interference.

In the FM mode, the signal was very good essentially full quieting for the first 1 ½ miles.  From the 1 ¾ mile mark to the 2 ¾ mile mark, the signal was readable with some RF noise.  At the 3-mile mark, the signal was very noisy but readable.  At the 3 ¼ mile mark, the signal was very noisy and unreadable.

In conclusion, the FM signal transmissions outperformed the AM signal transmissions.

Based on these results on what would be the best Off-Road Trail Comm., I think the FM CB transmission has a good chance of being a very good trail comm.  I think a test on an actual off-road trail with trees/foliage would be warranted to see what would be best under trail conditions. 

There is no doubt that any VHF or UHF mobile radio with RF output power higher than an FRS would perform better.  I think that I just may conduct that test once I get my XTL VHF radio installed in my Jeep which will occur in the near future so I can conduct a comparison radio test between the VHF & UHF radios on the trail.

[marcspaz]

@nokones i have said many times that there is a huge advantage with CB over FRS or GMRS, because HF has LOS propagation, like GMRS, but also has the advantage of Ground Wave and Sky Wave propagation as well. However, very few people I have met in my entire life, have a properly installed CB. Even fewer have SSB to take advantage of the extra power and sideband performance characteristics. I only know one person (personally) that has an FM CB.  Bad performance of poorly installed factory stock AM radios that only put out 1 or 2 watts and 75%-80% modulation on a good day, and the lack of operators with compatible gear for SSB led me to recommend the much more powerful and installation forgiving GMRS.

 

I have an AM / FM CB. Ive done a test similar to what you mentioned, comparing AM CB to FM VHF and UHF. While I didn't compare CB AM to CB FM, my results showed a dramatic range improvement with a 50w GMRS radio compared to my well performing AM CB. Living here in VA, I should try to find some time to duplicate your test, to see how terrain and woods impact performance. I'll have to see if I can get the one person I know with an FM CB to run some tests with me.

[WRQC527]

50 minutes ago, marcspaz said:

there is a huge advantage with CB over FRS or GMRS

CB has better slang, too. In fact, I think that's one thing missing from GMRS. 

[nokones]

1 hour ago, marcspaz said:

@nokones i have said many times that there is a huge advantage with CB over FRS or GMRS, because HF has LOS propagation, like GMRS, but also has the advantage of Ground Wave and Sky Wave propagation as well. However, very few people I have met in my entire life, have a properly installed CB. Even fewer have SSB to take advantage of the extra power and sideband performance characteristics. I only know one person (personally) that has an FM CB.  Bad performance of poorly installed factory stock AM radios that only put out 1 or 2 watts and 75%-80% modulation on a good day, and the lack of operators with compatible gear for SSB led me to recommend the much more powerful and installation forgiving GMRS.

 

I have an AM / FM CB. Ive done a test similar to what you mentioned, comparing AM CB to FM VHF and UHF. While I didn't compare CB AM to CB FM, my results showed a dramatic range improvement with a 50w GMRS radio compared to my well performing AM CB. Living here in VA, I should try to find some time to duplicate your test, to see how terrain and woods impact performance. I'll have to see if I can get the one person I know with an FM CB to run some tests with me.

Today was my first opportunity to try out the CB FM mode. I had a friend help me with my own CB radio, I took out of my Dually Diesel, and put it in his Avalanche. He was the transmitting source. I actually like the audio quality of the CB FM radio mode.

If I remember correctly, my modulation peaked at 85% and my CB radios are not modified.

[nokones]

@Marcspaz Too bad we live many States apart. I would love to join you in your test.

[marcspaz]

 

Since several of you are somewhat local to Uwharrie, I figured I would share this little gem with you.  Its a video of the gatekeeper and v-notch of 390 / Daniel.  There are some fairly funny parts; especially the last 2 minutes.

 

 

[AdmiralCochrane]

Marc, I am going to get an FM CB sometime in the next year or two, but haven't decided how or where to mount it in my Jeep.  Pretty sure we are only an hour or so apart (depending on traffic). We can probably both hit some of the same repeaters that are between us.  I actually haven't tried them in a while

[marcspaz]

29 minutes ago, AdmiralCochrane said:

Marc, I am going to get an FM CB sometime in the next year or two, but haven't decided how or where to mount it in my Jeep.  Pretty sure we are only an hour or so apart (depending on traffic). We can probably both hit some of the same repeaters that are between us.  I actually haven't tried them in a while

 

I would be happy to lend a hand. Most of my mobile radio use has been in various Jeeps over the decades. I can definitely help you get a great performing antenna setup. 

 

I have a Cobra 75 All Road, but if you can find one, the President McKinley 2 is probably the best one I have ever seen. I wish I bought one, but missed the short window to buy a new one.

[AdmiralCochrane]

Yeah I was looking at that radio when it came out

[nokones]

16 hours ago, marcspaz said:

 

Since several of you are somewhat local to Uwharrie, I figured I would share this little gem with you.  Its a video of the gatekeeper and v-notch of 390 / Daniel.  There are some fairly funny parts; especially the last 2 minutes.

 

 

I may want to forego this trail so I can keep my fenders on.

[nokones]

11 hours ago, AdmiralCochrane said:

Marc, I am going to get an FM CB sometime in the next year or two, but haven't decided how or where to mount it in my Jeep.  Pretty sure we are only an hour or so apart (depending on traffic). We can probably both hit some of the same repeaters that are between us.  I actually haven't tried them in a while

This is where I mounted my Cobra 25 LTD Classic AM/FM CB Radio in my 23 Wrangler Rubi 2 Dr.

[marcspaz]

That is typically where I mount my full-body radios, too. The tricky part is the antenna. Many people make the mistake of using a 3/4 mount and the nylon washer is trash in days... maybe weeks. But if you install a UHF mount with a UHF to 3/4 adapter, you get an incredibly strong mount. From there, it's just a matter of grounding. 

[nokones]

I'm just finishing up with a third radio in my 23 Wrangler Rubi 2 Dr. to complement my Motorola XTL5000 High Powered Remote Mount UHF radio and my Cobra 25 LTD Classic AM/FM CB Radio. My third radio is a Motorola XTL2500 Remote Mount 840 Channel VHF radio. I 'm going to use a Laird TE Connectivity B1442 Base Load Non-Groundplane antenna hanging on the driver's side at the cowl with a Rugged Radio mount.

I have the radio installed and the electrical connected however, I am waiting on a Powerwerx Anderson Power Pole Distribution Block. I had to remove my CB, Garmin Navigation Systems from the existing distribution block in order to power the newly installed radio.

Essentially, all I have left to do, is finished up on the antenna mount grounding system, running the NMO antenna mount cable, install the Mini UHF connector on the cable, and tune the antenna.

I intend to do that tomorrow. I called it a day at 3PM Arizona time. I've been out in the garage since 8AM and it was 113 degrees.

Then, I will need to program the radio.

 

[marcspaz]

Very nice!!!

[nokones]

6 minutes ago, marcspaz said:

Very nice!!!

Thank you.

I just had to feed my addiction. I won't have many freqs program except for the Part 90 Business Radio Service freqs I'm licensed for, and the MURS channels for receive only since I can't get radio powered down to 2 watts so I can listen in my travels. The CPS will only allow me to take it to 10 watts.

[nokones]

Well, tuning my Laird/ TE Connectively B1442 Non-Groundplane antenna was very eventful and educational and I wasted a perfect and my last spare mini-UHF connector for nothing. I guess I got sorta impatient and less-than-confident with myself regarding installing the connector on the antenna coax.

My VSWR reading was buried in the infinity zone and my 50-watt radio was measured with 10 watts forward with a bunch of reflected power according to my recently calibrated Bird 43 meter and slug. Humm, I may have a short or open circuit somewhere in the coax or at the mount.

So, just be on the safe side, I get my Telewave In-Line RF Watt meter and check the readings again and they were the same. Also, I disconnected the antenna lead and connected a dummy load and I was transmitting 50 watts.

So, thinking that I may have screwed up the installation of the mini-UHF connector on the coax, I decided to whack off the mini-UHF connector and install a PL 259 connector. The VSWR reading was no different than the mini-UHF connector at that point, I thought that I may have whacked off and wasted a perfectly installed mini-UHF connector unnecessarily.

I decided to use a magmount to check the antenna and the VSWR was 8 or so but, I haven't cut the antenna yet. So, I cut the antenna based on the cut-chart for my targeted center resonance of 154 Megs which I whacked off 6 inches of the antenna element. The VSWR was 4+. Ok, at least the antenna is good and heading in the right direction and no doubt that the antenna element at full length was contributing to the infinity reading.

So, I decided to start checking the antenna grounding system. My newly installed ground strap definitely had ground continuity to the mounting bolt, but not to the mounting bracket. I removed the bracket and wire-wheeled the paint off the bracket and reinstalled the bracket, and I had ground continuity at the bracket for the antenna coax mount to make a bonded ground.

I reinstalled the antenna and mounting bracket to the vehicle, and I decided to start tuning the antenna with a Rig-Expert AA-650 Antenna Analyzer. I got to 1.4:1 VSWR at 154 Megs by cutting off 4 more inches of the antenna element to make a total of 10 inches that were cut-off and 4 inches less than what the cut chart specified.

I decided to check the forward and reflected power with the Bird and my readings were a tad 50+ forward and what I estimate something way less than a watt reflected and the needle movement came pretting close of representing a VSWR of 1.3:1. That made me very happy.

Very valuable lesson learned and I have extra mini-UHF connectors on order, but, I'll leave the PL 259 on the cable.

[StogieVol]

@marcspaz I am new to the video editing and took the time to make one on CapCut, but when I went to download it said I didn't have enough space to do it. It wanted me to pay.... So, I have not gotten a full video done yet. Not sure I want to pay for editing yet. If that makes sense. 

[Socalgmrs]

On 9/30/2024 at 7:49 AM, nokones said:

Well, tuning my Laird/ TE Connectively B1442 Non-Groundplane antenna was very eventful and educational and I wasted a perfect and my last spare mini-UHF connector for nothing. I guess I got sorta impatient and less-than-confident with myself regarding installing the connector on the antenna coax.

My VSWR reading was buried in the infinity zone and my 50-watt radio was measured with 10 watts forward with a bunch of reflected power according to my recently calibrated Bird 43 meter and slug. Humm, I may have a short or open circuit somewhere in the coax or at the mount.

So, just be on the safe side, I get my Telewave In-Line RF Watt meter and check the readings again and they were the same. Also, I disconnected the antenna lead and connected a dummy load and I was transmitting 50 watts.

So, thinking that I may have screwed up the installation of the mini-UHF connector on the coax, I decided to whack off the mini-UHF connector and install a PL 259 connector. The VSWR reading was no different than the mini-UHF connector at that point, I thought that I may have whacked off and wasted a perfectly installed mini-UHF connector unnecessarily.

I decided to use a magmount to check the antenna and the VSWR was 8 or so but, I haven't cut the antenna yet. So, I cut the antenna based on the cut-chart for my targeted center resonance of 154 Megs which I whacked off 6 inches of the antenna element. The VSWR was 4+. Ok, at least the antenna is good and heading in the right direction and no doubt that the antenna element at full length was contributing to the infinity reading.

So, I decided to start checking the antenna grounding system. My newly installed ground strap definitely had ground continuity to the mounting bolt, but not to the mounting bracket. I removed the bracket and wire-wheeled the paint off the bracket and reinstalled the bracket, and I had ground continuity at the bracket for the antenna coax mount to make a bonded ground.

I reinstalled the antenna and mounting bracket to the vehicle, and I decided to start tuning the antenna with a Rig-Expert AA-650 Antenna Analyzer. I got to 1.4:1 VSWR at 154 Megs by cutting off 4 more inches of the antenna element to make a total of 10 inches that were cut-off and 4 inches less than what the cut chart specified.

I decided to check the forward and reflected power with the Bird and my readings were a tad 50+ forward and what I estimate something way less than a watt reflected and the needle movement came pretting close of representing a VSWR of 1.3:1. That made me very happy.

Very valuable lesson learned and I have extra mini-UHF connectors on order, but, I'll leave the PL 259 on the cable.

Gotta ask why a ground strap.  I haven’t used a ground strap since the cb days.  Never once on an gmrs set up.
Also gonna be the worst possible location to mount an antenna.  

[marcspaz]

4 hours ago, StogieVol said:

@marcspaz I am new to the video editing and took the time to make one on CapCut, but when I went to download it said I didn't have enough space to do it. It wanted me to pay.... So, I have not gotten a full video done yet. Not sure I want to pay for editing yet. If that makes sense. 

 

Use DaVinci Resolve.  It's the same software many commercial movie production companies use, and is the top rated software used in Hollywood.  The best part is, its free for folks like us.  Commercial licenses don't give us anything we need.

 

https://www.blackmagicdesign.com/products/davinciresolve

 

 

I use Corel VideoStudio also, which is $80 to buy, but is way easier to use when I am doing something quick.

https://www.videostudiopro.com/en/

 

 

[nokones]

2 hours ago, WRXP381 said:

Gotta ask why a ground strap.  I haven’t used a ground strap since the cb days.  Never once on an gmrs set up.
Also gonna be the worst possible location to mount an antenna.  

Because they make a good ground and I have had this for centuries so I decided to use it. There was no ground at the antenna bracket except through the coax. With all the electronics and if the antenna mount isn't grounded you are subject to transmitting noise to other electrical components. This antenna was not GMRS or UHF. It is a VHF Highband 150 Meg antenna.

[RayDiddio]

4 hours ago, marcspaz said:

 

Use DaVinci Resolve.  It's the same software many commercial movie production companies use, and is the top rated software used in Hollywood.  The best part is, its free for folks like us.  Commercial licenses don't give us anything we need.

 

https://www.blackmagicdesign.com/products/davinciresolve

 

 

I use Corel VideoStudio also, which is $80 to buy, but is way easier to use when I am doing something quick.

https://www.videostudiopro.com/en/

 

 

Yes. Resolve is amazing. It's got a small learning curve but once you get going it really just does what you need.

The other one I would recommend is Sony Vegas, but Resolve is polished and nice.

[nokones]

17 hours ago, WRXP381 said:

Also gonna be the worst possible location to mount an antenna.  

Is there a better location on a 23 Jeep Wrangler for a VHF Highband non-groundplane Laird B1442N antenna? There is no such thing as an adequate antenna mounting location on a Wrangler.

These three locations are the best there is for a Wrangler and are being used for my Motorola XTL5000 UHF, Motorola XTL2500 VHF Highband, and my Cobra 25 LTD Classic AM/FM CB Radios.

[Socalgmrs]

Haha .  The last one is the best option I’ve been jeeping for over 40years.  I’ve built jeeps and off road trucks as a living for over 30years. I’ve installed 1000s of cbs gmrs and hams.  The front fender in a line of sight frequency like 460 is the worst possible place to mount anytning.  I see by the paint and over all appearance of your jeep this really isn’t a problem, but the fender mount is also the most susceptible to major damage.  Any one I’ve ever off roaded with that had a fender mount anything has ripped it right off in the bushes.  You have over spent big on the jeep and midland radio and lair antenna but then it gets neutered but being mounted in a place that it won’t work very well.   When I off road I need my radios to transmit a good distance in all directions.  Not just forward to the next jeep.  

[nokones]

1 hour ago, WRXP381 said:

Haha .  The last one is the best option I’ve been jeeping for over 40years.  I’ve built jeeps and off road trucks as a living for over 30years. I’ve installed 1000s of cbs gmrs and hams.  The front fender in a line of sight frequency like 460 is the worst possible place to mount anytning.  I see by the paint and over all appearance of your jeep this really isn’t a problem, but the fender mount is also the most susceptible to major damage.  Any one I’ve ever off roaded with that had a fender mount anything has ripped it right off in the bushes.  You have over spent big on the jeep and midland radio and lair antenna but then it gets neutered but being mounted in a place that it won’t work very well.   When I off road I need my radios to transmit a good distance in all directions.  Not just forward to the next jeep.  

My UHF antenna is on the rear glass and I have no problem hitting repeaters that I need to hit 40 or so miles away, and have communicated a good 15 miles simplex car-to-car. Also, I am able to hear FRS traffic approx 5 miles away.  I can't complained about the performance of the glass-mount antenna, I am totally happy with it.

The left-front fender mount is my VHF Highband antenna and is essentially will be simplex (151, 154, & 158 Freqs) car-to-car operations. I'm not a Amateur Radio Operator thus no 2M freqs programmed. The CB Antenna is self explanatory and I get about 2 1/2 miles AM and 3 1/4 miles FM.

Oh by the way, there is no Midland radio in play in this vehicle. I need to have the ability of communicating on Part 90 UHF freqs. with both analog and P25 Digital emissions, so that means Motorola as noted. I also require the same emissions capabilities for the VHF Highband Motorola radio. 

Also, you did a great job negatively commenting on my antenna mounting locations and the fact I way over spent on my Jeep build but you never did provided/offer any expert opinion, if you even to happen to possess those expertises, on better antenna mounting locations for a 23 Wrangler.

Did I over spend? Well, I really didn't care what I spent on the overall build. I went top notch stuff on everything and essentially replaced just about every suspension, steering, and driveline components at about 4,000 miles on the odometer, for reliability and to reduce the probability of a breakdown on the trail. I also didn't hold back from getting the required/essential top-notch trail recovery gear and equipment.

Maybe I did spend more money then you or anyone else would have but, I don't deal or buy cheap inferior low grade POS junk. I only deal and buy quality products, stuff they would use in a public safety environment for the radio components, and as for the Jeep itself only race type quality components. I don't care if it cost more then what you would want to spend. I am totally happy with the total build and I immediately resolved and learned from the minor regrets of the early build stages.

If you ever see any of my racecar builds, you will never see any corners cut or cheap POS inferior parts on them either.