I would think it would work as you mentioned simply switching the coax cable and power and using the mount as the platform to mount the GRMC antenna, why wouldn't it work.
Do you guys still use CB radios?
- Thread starter JeepDew
- Start date
I was mostly wondering if I could keep the same style (or even the same altogether) antenna. All the ones I can find seem to be some sort of magnetic base I don't understand. Can I get a regular style CB antenna that works with the GRMS radio? I don't entirely understand the magnetic mounts and how I would go about easily switching between the two.
Maybe I'm being dumb, but how exactly does this thing work? You just stick it anywhere and it stays? I can't seem to find a normal antenna that says it is for a GRMS radio.
https://www.rightchannelradios.com/collections/gmrs/products/magnet-mount-antenna-kit-for-gmrs
I'm not a subject matter expert in that area but my communications experience from the Navy tells me your probably going to have to go with another antenna. I recommend you call a HAM radio outlet store, most of the folks who work there are geeks and know there radio's and antenna matching.
Ya, with that magnetic base just find a flat location that is metal and it should stay put.
Most of the good GMRS antennas I've looked at use an NMO mount, which is the same type of mount typically used for 70cm and 2m ham.
CB antennas, on the other hand, typically use a 3/8" stud mount.
Although I have seen 3/8" stud mount antennas for 2m ham, and I think there may also be an NMO CB antenna on the market, the short answer is that it will require more than one antenna to do CB+ham or CB+GMRS or CB+ham+GMRS.
Not only are the mounts for the two types of antennas completely different, the deal killer is that the frequency bands require entirely different length antennas. But that is a discussion for another thread.
CB antennas, on the other hand, typically use a 3/8" stud mount.
Although I have seen 3/8" stud mount antennas for 2m ham, and I think there may also be an NMO CB antenna on the market, the short answer is that it will require more than one antenna to do CB+ham or CB+GMRS or CB+ham+GMRS.
Not only are the mounts for the two types of antennas completely different, the deal killer is that the frequency bands require entirely different length antennas. But that is a discussion for another thread.
Concur, unless someone won't to design an antenna and slap together a device to electrically lengthen and shorten the antenna to match the wavelength to minimize resistance and zero reflection. Now, I'm digressing to my Navy Comms days.
Thanks for the help everyone. I was at the very least hoping to use the same antenna location and coax cable, but I don’t think that’ll work considering the mount type. I’ll have to find another place to throw the antenna and magnetic mount and run another cable. Thanks again.
A quick search found some GMRS antennas with UHF connectors (PL-259). My CB antenna mount has a UHF connector. So there you go, it can be done.
I’m working on installing a uniden 520xl since lots of folks and clubs still run CB’s.
But I’m going to get a Yaesu or a Baofeng handheld along with a ham license so I’ll have that base covered too.
The ham walkie talkies are so cheap, don’t see why you wouldn’t have both.
But I’m going to get a Yaesu or a Baofeng handheld along with a ham license so I’ll have that base covered too.
The ham walkie talkies are so cheap, don’t see why you wouldn’t have both.
Its not the coax that's the issue. NMO and 3/8 stud mounts both can use coax with PL-259/SO-239 connectors.
As noted above, CB and GMRS typically use different type antenna mounts, but even with the same mount the antenna lengths for different frequency bands would be entirely different which prevents a single antenna from being used for CB + GMRS, ham, etc.
Hi all. Reviving this thread to ask a closely related question: instead of looking for interchangeability between CB and GMRS or Ham, I'm just interested in interchangeability between GMRS and Ham. What antennas out there are good for both GMRS and dual-band Ham?
Someone on here (I'm forgetting at the moment) recently recommended the Comet CA-2x4SRNMO. Are any others known for being good at both dual-band Ham and GMRS?
Someone on here (I'm forgetting at the moment) recently recommended the Comet CA-2x4SRNMO. Are any others known for being good at both dual-band Ham and GMRS?
I'm running a Diamond on a magnet mount for my VHF/UHF rig, which covers the GMRS band. Nice antenna, blah, blah - very low SWR on both VHF and UHF with the ham radio - BUT - for whatever strange reason, SWR was horrid when connected to my Midland GMRS rig. *shrug* I have no explanation for it - perhaps the Midland isn't really a 50 ohm output? Its SWR is fine with the little "rubber ducky" antenna it came with!
Are you wanting to switch two radios to one antenna? I thought about that...
Are you wanting to switch two radios to one antenna? I thought about that...
abruzzi
Member
I use the Larsen 270. It’s what we use on all our police and fire vehicles. It is an NMO mount, and it lasts forever—mine I’ve had for ~15 years, and has moved from vehicle to vehicle. It’s on the longer side because it is not ground plane dependent. It’s not terribly cheap though.
https://www.dxengineering.com/parts/lsn-nmo2-70b
https://www.dxengineering.com/parts/lsn-nmo2-70b
The Larsen NMO 2/70SH pictured in Post #112 works quite well as a 2m/70cm antenna and surprisingly well in the GMRS frequencies although not tuned for them. It is 18" tall.
Another ham dual band antenna with decent performance in the GMRS frequencies although not tuned for them is the MFJ-1724B mag mount, also about 18" tall.
Sustained high power out of band Tx may cause heat issues, but brief transmissions should not be a problem. At lower power levels there isn't a problem Tx with either antenna. In theory, the quality of GMRS Tx on a ham dual band antenna should also be compromised, but I have not experienced any problems the few times I used these two antennas with a GMRS radio.
For a longer antenna, I would have no qualms using the 34.5" Larsen NMO 2/70 for 2m/70cm/GMRS Tx/Rx. It is linked in the post above. I have one that I often use in open country where there is little likelihood of whacking tree branches.
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Thanks, and yes, just wondering if I can avoid a new antenna if I do end up getting into GMRS. (You've probably seen in other threads that I'm a bit resistant to it!)
It's the black version vs the chrome one. It worked well out of the box for me.