my experience with GMRS so far

dreadlocks

Well-known member
there's only 8 GMRS frequencies that require a license, and those are the Repeater Inputs.. shouldn't really be working those on simplex, they should be free so repeaters can be sensitive to handhelds.. I heard someone last time I was out camping working it simplex, they were offroading w/a drone following em apparently.. sigh.

everything else you share with FRS, which should be power limited so feel free to stomp on those freeloaders if you must :p
 

Billoftt

Active member
...they were offroading w/a drone following em apparently.. sigh.
But did you really go off-roading if you didn't share a video on social media? It's just like working out, you can't make any serious gains unless you Instagram it and your steps won't matter unless it's on Facebook.
 

BigDaveZJ

Adventurer
Gotcha, a lot of the info on the web seems to be prior to the 2017 changes. I thought there were dedicated GMRS only channels, but its really just that we can use more power on the FRS channels with our GMRS.

I need to look into the repeaters a bit more too. There's only a couple I can hit from where I usually am and they don't appear to work with the Midland stuff I have.
 

DaveInDenver

Expedition Leader
Gotcha, a lot of the info on the web seems to be prior to the 2017 changes. I thought there were dedicated GMRS only channels, but its really just that we can use more power on the FRS channels with our GMRS.

I need to look into the repeaters a bit more too. There's only a couple I can hit from where I usually am and they don't appear to work with the Midland stuff I have.
After the 2017 revisions GMRS and FRS share most channels except for the repeater inputs, which are GMRS-only. The stipulation is FRS must use lower power, have a fixed antenna and is the secondary user to the primary user (e.g. the one who bought the license).

It's likely the hooligans dreadlock came across were using a non-Type approved radio since a properly made GMRS radio wouldn't transmit on the repeater inputs without using an offset (if it's repeater capable at all, most only work simplex on the repeater output frequency) and an FRS radio wouldn't transmit at all on GMRS input frequencies. But don't ask, don't tell w.r.t. non-GMRS radios, eh?
 

BigDaveZJ

Adventurer
Also, I think rather than just stomping on the guys at Ace with my 15w radio I think I'll just use it to page them to come out and refill my propane tanks rather than using the buzzer they have out there, lol.
 

dreadlocks

Well-known member
They were toned up, I announced my callsign and said I was listening and they didnt hear me, or respond anyhow.. honestly, using em for simplex if your licensed and need some space would not be end of the world, using it is better than letting it sit and rot because repeater network is so sparse.. I actually have my radios programed to do that as a failover simplex (low power) channel just incase.. BUT, they are not tone squelched so I can hear any other traffic on em, if you tone up then you cant monitor it for traffic, or worse you could use the same tone that keys up a repeater inadvertently.

The only time I think I remember needing to use em simplex was at races/events when everyone and grandma has a FRS.. dunno why you'd even need it in BFE, not like you dont have your pick of frequencies.. I also keep it programmed as a backup in case someone strays outside of repeater range, can still hear em on that channel if you get within simplex range.. but haven't needed to use it for that purpose.

All my handheld are programed to just a few select channels and tones, then a couple of backup channels and then an emergency frequency (National Call).. all of it's unique to my setup, but its idiot proof and cheap as hell to get 6 good durable mini radios and a 6 gang charger.. nobody but the kids liked my old 5lb police radios you could beat someone to death with, honestly I didnt either.. My vehicle is scanning when its parked at camp.

Now that you can buy off the shelf mobile radios that support repeaters, I'm really debating spending about ~$1500 for a legit licensed repeater here soon (then another $400 in antenna) instead of my hackeyshack one, it'd be capable of repeating all the tones.. really any tone could activate it, I'd be a bit annoyed if someone was working it simplex accidently because they were too dense to know any better.. the idea of having call groups would be nice, especially if I open it up to public use.

My program is:
  • #1 My Repeater Duplex (Tone/Primary)
  • #2 My Repeater Output Simplex (Tone/Primary Simplex)
  • #3-#6 Repeater Output Simplex (Tone/Secondary Simplex)
  • #9 - National Emergency Simplex (Tone/Wide)
  • #15 - Repeater Talkabout (Duplex Rx/Tx Switched)
  • #20-#50 - Backup Frequencies - All Frequencies Sequentially Simplex (No Tone)
99.999% of the time I'm using the top 2 channels, and it just depends if I have the repeater with me and setup or not.. the only channels scanned by handhelds are #2-#9, and I lock all the buttons but xmit when I hand em out to most people.
 
Last edited:

BigDaveZJ

Adventurer
Made it out to 22 miles over the weekend. Using the coverage map from a few posts back I tried to find a spot that was convenient for me to get to that would push the range further than I have so far. I was in my truck, MXT275 with the Midland 6db gain antenna in a stake pocket mount on my truck. My wife was back at camp with a GXT1000 handheld and the MXT115 with 6db gain antenna on the ladder of our 5th wheel that I've mentioned before. The handheld worked better than MXT115 for both TX and RX. Kind of strange. Wondering if this is related to ground plane?
 

Recommended books for Overlanding

prerunner1982

Adventurer
I would think the ladder should be more than enough metal on it's own. You could always try making some ground radials for the antenna, see if that changes anything.
 

BigDaveZJ

Adventurer
I think I need to spend some time studying up on ground planes as well. I might be having a bit of a mental block on how they work too. If I envision the antenna as an upside down T, the antenna itself is the vertical part and the ground plane is the horizontal piece. If radio waves come from above in a RX the ground plane reflects it back to the antenna, but if it comes from below my brain tells me it would reflect the waves away from the antenna and hinder performance.

I am sure this is wrong as I admittedly know nothing about ground plane other than you're supposed to have some, just how my brain imagines it working. Time to fire up the googles and learn some more about it.
 

DaveInDenver

Expedition Leader
I think I need to spend some time studying up on ground planes as well. I might be having a bit of a mental block on how they work too. If I envision the antenna as an upside down T, the antenna itself is the vertical part and the ground plane is the horizontal piece. If radio waves come from above in a RX the ground plane reflects it back to the antenna, but if it comes from below my brain tells me it would reflect the waves away from the antenna and hinder performance.

I am sure this is wrong as I admittedly know nothing about ground plane other than you're supposed to have some, just how my brain imagines it working. Time to fire up the googles and learn some more about it.
Ground planes and counterpoises are used interchangeably in casual conversion but none the less your intuition that having an artificial ground plane will impact the radiation pattern is correct.

This was taken from Antenna Theory (2nd Edition) by Constantine Balanis, originally in the chapter on antenna apertures and specifically page 641 within chapter 12.10, Ground Plane Edge Effects: The Geometrical Theory of Diffraction when discussing a 2 wavelength sized ground plane under a monopole.

Being down nearly 20dB is very significant (magnitude of 100) but not completely deaf.


08231901.jpg
 
Last edited:

MidlandUSA

Supporting Sponsor
What is "Picket Fencing"?

I, like many hams (K4WGA) also have a GMRS license (WRCY713). I view GMRS basically as CB's with less noise, and they are good for family and vehicle communications. Plus I can get a phantom antenna on my wife's minivan without her getting pissed at me.

I do own a Midland MXT115 and an MXT275. Both have pretty bad "Picket Fencing" issues above 15 mph though.
Hey Bill, this is the 2nd post we have seen of you telling people that the Midland MicroMobiles have bad "Picket Fencing" which is the first time we have heard of this on any forum online. If you are having issues with your particular radios please give customer service a call at 816-241-8500 M-F 8am-4:3pm CT and a customer service representative will be happy to troubleshoot the issue for you. Thanks!
 

BigDaveZJ

Adventurer
So I'm trying to get a little more permanent mounting solution for the radio in my truck. It's currently just stashed in the center console. I'd like to remote mount them behind the back seat or something and have a better place to connect the mic to. It looks like connector is just a regular Cat 5 style. Is there any reason I couldn't just run a Cat 5 cable up to the dash somewhere from the back and plug the mic in to the Cat 5 cable?
 

dreadlocks

Well-known member
might need to add some chokes to it, I did to get rid of some noise.. I ran cat6 all the way to the back, crimped on that end and punchdown box under the dash and it works just fine... chokes are right before the radio.
 
Top