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Well, no, narrowband FM is typically only 6.25 kHz and the few AM transmitters I’ve used do 6 kHz (up to 4 kHz per sideband on SSB on my ham radio). I would believe data sheets on modern am/fm CB radios if you want to do some research.

You are correct, the signal doesn't travel any farther. It is the inverse, an FM receiver will reject a stronger signal until it is strong enough to "lock on".

When I was at Ft Devens learning the whys and wherefores of ECM/ECCM, we had a window of time to Jam the FM Audio on a local TV station. Using a Dummy Load running 1500w, we would still jam TV sets within a 1 mile radius of the Transmitter (AN/TLQ-17). Lotsa of fun changing the dialog on the Soaps. That and SERE Training were the most fun I had before my PCS.

Authorized, yes. But FM requires all of that bandwidth and AM doesn't.

We got in trouble with the local TV station in Rolla, MO when I was stationed at Ft Leonardwood. We would have the basic trainees tune the PRC77 radios to the TV station and one trainee keyed up the mic. It didn't take long for the TV station to call the post commander's office to complain. We would occasionally upset some sad ham within the 6m band. But as you stated, once we told them whoever we were and that we were the primary users, complaints stopped. The PRC25 and PRC77, along with vehicle mounted radios have a low band (30 - 50 MHz) and a high band (51 - 70 MHZ). The SINCGARS frequency hopping radios use 30 - 88 MHz. The state of Missouri still uses 42, 44, and 46 MHZ for public safety and emergency management. Granted these frequencies are more as a backup system now days. And other states still use the VHF low band also. So that will need to be taken into consideration with the propels to add VHF Low to GMRS or even to amateur radio.

AM is easier to decode when it's all scrambled up from the atmosphere. You can hear the voice even with lots of static. In FM if the signal is garbled the decoding doesn't work well at all.

On CB, FM and AM are authorized to use exactly the same bandwidth: 95.973 CBRS authorized bandwidth. Each CBRS transmitter type must be designed such that the occupied bandwidth does not exceed the authorized bandwidth for the emission type under test. (a) AM and FM. The authorized bandwidth for emission types A3E and F3E is 8 kHz. (b) SSB. The authorized bandwidth for emission types J3E, R3E, and H3E is 4 kHz.

i think AM is going to be the winner in shooting skip over FM just because AM uses much less bandwidth which lessens the effects of the atmosphere and other conditions.. FM will be more clear in audio in shorter range but also be more acceptable to degradation over range because of its bandwidth characteristics... AM transmission is defianlty better for longer distance transmission

For $25 you won't get the performance you expect. There are other things you should look at such as RX sensitivity, de-sense, channel isolation, spectrum free from harmonics, spur response, frequency accuracy and stability etc. Most people don't have the equipment to do these kinds of tests. If you know somebody with a good quality commercial radio grade service monitor I would stick the radio on it and run some tests. Some decent used ones run around $1K plus used. I believe one of the members of this forum got a used one in this price range a while back specifically for testing his radios and repeaters. A few that can do auto tune up, radio calibration, and digital mode testing can run over $10K to $20K plus used. For example the cheap, $25, Baofeng UV-5R early version had dirty transmitters. They were multi-band radios. You could talk on several all at the same time! I'm not knocking your desire to do a video on the radio. But remember you give people the idea the radio is the best thing since sliced bread, people buy them because they're cheap, and now the local bands have issues with crappy signals on the air. UV-5R VHF Harmonics Test.pdf

I don't see why not. I talk on 10m FM simplex all over the states when the band is open, especially to the West Coast from MN, and have had a few contacts into Europe as well.

Don't recall the Group name, but recently I did see some photos and a posting on a FB CB page with some very much massive set ups, with congrats to the "Key Down" winners, etc.

So, FM CB should be able to "shoot skip" about as effectively as AM? That's a new thought to me.

So, FM CB should be able to "shoot skip" about as effectively as AM? That's a new thought to me.

I wrote the FCC in favor of this petition and also suggested in my letter if the FCC favored this proposal they should also use this opportunity to clean up the exisitng GMRS rules and clarify existting rules. I.e. Limit GMRS repeater ownership to 3 or less, do not permit cross state GMRS Repeater ownership, clarify rules related to 'charging for use of a repeater". Rewrite current rules on Linking so that it is clear the practice is simply illegal and take the confusion of other networks out of the rules. .. This wold be a great opportunity for the FCC to clean up all the gray areas with the rules.. One of my buddies in Riverside (FCC) office says this proposal actulliy has some traction.. The more we write in favor of this the better chance it has.

https://ised-isde.canada.ca/site/spectrum-management-telecommunications/en/official-publications/policies/spectrum-utilization-policies-sp/sp-462467-mhz-spectrum-utilization-policy-permit-licence-exempt-devices-land-mobile-frequency-sub

Back in my ASA/INSCOM days we used to mess with the poor hams on 6m when we were practicing ECM. Most were pretty cool once we explained that A, we weren't governed by any FCC regulations and B, we were the primary users of the band. Some got a bit "Sad Hammy" on us, but 1500 watts does wonders on VHF.

It looks like GMRS is limited to 0.5 watts on some channels and 2 watts on others and they aren't allowed to use repeaters. GMRS shares some channels with FRS and it's limited to 0.5 watts on those channels. FRS has 6 channels shared with GMRS and 9 that are FRS only and FRS is limited to 0.5 watts. It makes me wonder why they have two separate services. It seems they could just lump them all together with designated power limits on each channel.

its got a way better chance of happening then Linking on GMRS.. You might be wrong on this one.. I woild give it a better chance though. maybe in 2 years.. Lets Bookmark that comment... Looser buys the other a ice cold tall beer

I agree..

The Talk Around Feature is selected from the menu and you have to follow the procedure to enable the feature. I don't recall if you select and enable the feature if it is global to the radio on the RP channels or just channel specific on the selected channel.

I think it would be a good idea to have some lowband VHF channels allocated for the Personal Radio Service with repeater operation like GMRS. Finding vault and tower space and services for a lowband VHF remote repeater will be challenging and may discourage such a project. The geographical lowband plan still exist and requires frequency coordination, pursuant to Part 90 rules and regs. At this time, it doesn't appear there are any lowband VHF spectrum allocated/available for the Personal and/or Amateur Radio Services. 30 - Business Radio 31 - Forestry Conservation and Business Radio 33 - Fire 35 - Business Radio 37 - Police 39 - Police 42 - State Police Only 43 - Business Radio 44 - Some Police and Some Business Radio 45 -Police 46 - Fire 47 - Highways & Roads 48 - Utilities 49 - Business Radio 32, 34, 36, 38, 40, and 41 - These freqs are not regulated by Part 90 and the FCC. They may be allocated to and regulated by NTIA.

I kinda recall that Canada allows GMRS, but not with repeaters and I don't remember what the RF power limitations were.

My Surecom will only test up to 525MHz so I can't get a power reading at 900MHz but I did test all the other frequencies. There's plenty of videos on YouTube about the RT-900 you can watch and I plan on doing one tomorrow to post to my channel. I'm also getting some properly tuned antennas for 900MHz to use because nothing I currently have is tuned for that frequency. Also, without actually getting one you can't just presume that it's junk. It's actually worked very well at 2M, 1.25M and 70cm hitting repeaters over 20 miles away with the Nagoya 320a antenna I have on it. I'd say pick one up and give it a try, what have you got to loose? At the most you've dropped $25 bucks on something that will work on several different bands and would be a good beater radio to keep in the truck or as a back up to your other radios.

I was trying to reach a repeater that should have been nearby (in reference to it's mapped location) but not in sight by any means on my an older model MXT-400 (NOT programmable). I had spoken on another repeater (different frequency) that overlaps the signal of the one I was looking for and see if anyone could hear my transmission after changing frequencies. They could see my signal (Repeater busy) but could not heard any output from the repeater. I did some research on my unit and was reminded of the "Talk Around Function" allows one to talk to a group of other radios in case the repeater is temporarily out of range or no longer activated. This function allows "you to continue" using the RX/TX frequencies, PL, code to communicate with the group. That is how I understand it. I checked my Operations Manual and went thru the motions to insure this was not set for Talk Around on the frequency I was using and it wasn't. Could this function be set on another frequency and affectioning all the other frequencies? I wouldn't think so but.... Maybe I just need to reboot the whole kit & caboodle.

If you can put it on a scope and frequency counter to verify that. Then the next test is output power. That I expect to suck. Trying to design a tuned power amp stage to have that kind of bandwidth is going to cost a lot more than $25. I know many people thought their D878’s could do 1.25M since they could program in the frequencies. However the real results at the antenna port just wasn’t there to make it worth the trouble.