Jones

Greg,
 
I fully agree with this, and I'll admit that I was trying to simplify something that just isn't so simple.  If the antenna has a high SWR, a wattmeter may not read correctly anyway, due to the reflected voltage not necessarily being at a half-wave point in the return path.
 
The main problem is that many consumer-grade RF power meters do not actually measure power.  They measure a sample voltage at a given point in the transmission line, and estimate power based on a low-voltage/high-current place on the line.  Reflected power, depending on the phase and time of arrival at the metering point will either add to, or subtract from, that representative voltage, giving a false reading.  For example, if your input jumper is too long, and falls at a voltage high point in the overall line length, and the reflected power from a mismatched antenna also falls at a voltage high at that same point in the line, your voltage-driven power meter may show 45 Watts output from a 25 Watt transmitter.  With a half-wave input jumper, you will start out with a known voltage low point. A mismatched load will still cause a false reading, but usually not as severe. - Your reading will be "less wrong".
 
I guess in summary, if you want to measure output power of your transmitter, use a known good terminating resistor - A.K.A. Dummy Load. I've seen good 50 Ohm terminators selling for less than $40.

Info for those not familiar...
The popular "DB" line of antennas is/was made by Decibel Products, but due to various corporate buyouts and mergers became Andrew, and now CommScope.
 
Decibel Products DB-420
Andrew DB-420
CommScope DB-420
 
They are all one and the same.
 
...and they are my first choice.  The whole DB series, not just the 420.

The reading on a power meter will vary a LOT depending on where the meter sits in the overall total-length of coax cable.  To get an accurate reading, the meter MUST sit at an interval of 1/2 wavelength along the transmission line.  The only way to easily do this is by insuring that you are using a half-wave input jumper cable on your meter.
 
Cable electrical wavelength is figured by the Speed of Light (299,792,458 meters per second) divided by the frequency in Hertz, the dividend of which is multiplied by the velocity factor of the cable (look at the specs for the cable you are using).
 
For instance, if my meter's input jumper was made from RG-213u, I would see that the velocity factor for that cable is 0.66. (sometimes shown as 66%)
 
(NOTE: In this example, I have used 462.600 in the GMRS band as my desired frequency. 462,600,000 Hz)
 
Let's do the math: 299792458 / 462600000 = 0.6480597881539127 * Velocity factor of 0.66 = 0.4277194601815824 Meters.  That is a full-wavelength of cable, and we need a half wavelength, so cut it in half. So, your jumper cable into the meter should be about 21.5 centimeters long, or about 8.5 inches.
 
If you were using a smaller cable, like RG-58u with a foam dielectric, which has a velocity factor of 0.535, then you would need  .1734 Meter jumper, or about 6.8 inch jumper to correctly match the input of your meter.
 
If you are using just some random-length input jumper, particularly if it is over a full wavelength long, then you may not be even close to the half-wave point, depending on the length of the rest of the cable going to the antenna, and the meter will not read right.  If you use this calculated length of input jumper, accounting for its velocity factor, then whatever is on the output side makes no difference to the reading accuracy.
 
By the way, this rule goes for SWR meters as well as power meters.  If you set up your UHF antenna with a 3-foot truck-stop CB jumper going into your meter, then you are likely WAY out of 'whack'. These rules still apply at HF also.  It isn't as critical below 30 MHz since the wavelength is so long, but if you use a 4 or 5 foot long meter jumper at CB frequencies, it WILL be wrong. At 27.205 MHz, use a 6 inch jumper, or else a 9.6 foot one for accuracy.
 
Tech hint: I keep several different lengths of pre-made jumpers in my Bird watt meter case for different frequency bands that I normally work with, and have them all tagged as to what band range they are for.  The higher you go in frequency, the more critical this gets, and the SHORTER they get... sometimes TOO short, thus for 950 MHz, I keep a 15.6 inch jumper of LMR-400, which is 1.5 Wavelengths, but still on a calculated half-wavelength point in the line.  A 5.2 inch long LMR-400 jumper is too short to work with.
 
Long winded, sorry, but I hope this helps.
 
-Jones

The reading on a power meter will vary a LOT depending on where the meter sits in the overall total-length of coax cable.  To get an accurate reading, the meter MUST sit at an interval of 1/2 wavelength along the transmission line.  The only way to easily do this is by insuring that you are using a half-wave input jumper cable on your meter.
 
Cable electrical wavelength is figured by the Speed of Light (299,792,458 meters per second) divided by the frequency in Hertz, the dividend of which is multiplied by the velocity factor of the cable (look at the specs for the cable you are using).
 
For instance, if my meter's input jumper was made from RG-213u, I would see that the velocity factor for that cable is 0.66. (sometimes shown as 66%)
 
(NOTE: In this example, I have used 462.600 in the GMRS band as my desired frequency. 462,600,000 Hz)
 
Let's do the math: 299792458 / 462600000 = 0.6480597881539127 * Velocity factor of 0.66 = 0.4277194601815824 Meters.  That is a full-wavelength of cable, and we need a half wavelength, so cut it in half. So, your jumper cable into the meter should be about 21.5 centimeters long, or about 8.5 inches.
 
If you were using a smaller cable, like RG-58u with a foam dielectric, which has a velocity factor of 0.535, then you would need  .1734 Meter jumper, or about 6.8 inch jumper to correctly match the input of your meter.
 
If you are using just some random-length input jumper, particularly if it is over a full wavelength long, then you may not be even close to the half-wave point, depending on the length of the rest of the cable going to the antenna, and the meter will not read right.  If you use this calculated length of input jumper, accounting for its velocity factor, then whatever is on the output side makes no difference to the reading accuracy.
 
By the way, this rule goes for SWR meters as well as power meters.  If you set up your UHF antenna with a 3-foot truck-stop CB jumper going into your meter, then you are likely WAY out of 'whack'. These rules still apply at HF also.  It isn't as critical below 30 MHz since the wavelength is so long, but if you use a 4 or 5 foot long meter jumper at CB frequencies, it WILL be wrong. At 27.205 MHz, use a 6 inch jumper, or else a 9.6 foot one for accuracy.
 
Tech hint: I keep several different lengths of pre-made jumpers in my Bird watt meter case for different frequency bands that I normally work with, and have them all tagged as to what band range they are for.  The higher you go in frequency, the more critical this gets, and the SHORTER they get... sometimes TOO short, thus for 950 MHz, I keep a 15.6 inch jumper of LMR-400, which is 1.5 Wavelengths, but still on a calculated half-wavelength point in the line.  A 5.2 inch long LMR-400 jumper is too short to work with.
 
Long winded, sorry, but I hope this helps.
 
-Jones

Glad to help.  If you have any kind of jumper close to 7.5 inches or so, it will likely be close enough at 460MHz.  It may still show a difference in power levels between your different antennas, but not as drastic of a difference as your 2 foot jumper will show.  If you happen to hit it right on the half-wavelength mark, then there should be no noticeable difference between forward power level readings on any of your antennas, unless one of your antennas is bad -  then the transmitter might "fold back", or shut down for protection.
 
ALSO: If you want a true representation of the output power of your radio, don't measure it into an antenna, use a half-wave jumper into your meter, with a 50 Ohm dummy load connected directly to the output of your meter.
 
While I'm here, as long as reflected power is very low compared to forward, or if your SWR is less than 2:1, then it's close enough to work. If it's less than 1.7:1 then it's good. At 1.5:1, it's GREAT! Tweak it if you must, but the difference between 1.5:1 SWR and 1.1:1 SWR is not worth fighting for. In most cases, just follow the manufacturer's cutting chart.  ...and trying to fine-tune a quarter-wave stub at 460MHz is absolutely foolish.

The reading on a power meter will vary a LOT depending on where the meter sits in the overall total-length of coax cable.  To get an accurate reading, the meter MUST sit at an interval of 1/2 wavelength along the transmission line.  The only way to easily do this is by insuring that you are using a half-wave input jumper cable on your meter.
 
Cable electrical wavelength is figured by the Speed of Light (299,792,458 meters per second) divided by the frequency in Hertz, the dividend of which is multiplied by the velocity factor of the cable (look at the specs for the cable you are using).
 
For instance, if my meter's input jumper was made from RG-213u, I would see that the velocity factor for that cable is 0.66. (sometimes shown as 66%)
 
(NOTE: In this example, I have used 462.600 in the GMRS band as my desired frequency. 462,600,000 Hz)
 
Let's do the math: 299792458 / 462600000 = 0.6480597881539127 * Velocity factor of 0.66 = 0.4277194601815824 Meters.  That is a full-wavelength of cable, and we need a half wavelength, so cut it in half. So, your jumper cable into the meter should be about 21.5 centimeters long, or about 8.5 inches.
 
If you were using a smaller cable, like RG-58u with a foam dielectric, which has a velocity factor of 0.535, then you would need  .1734 Meter jumper, or about 6.8 inch jumper to correctly match the input of your meter.
 
If you are using just some random-length input jumper, particularly if it is over a full wavelength long, then you may not be even close to the half-wave point, depending on the length of the rest of the cable going to the antenna, and the meter will not read right.  If you use this calculated length of input jumper, accounting for its velocity factor, then whatever is on the output side makes no difference to the reading accuracy.
 
By the way, this rule goes for SWR meters as well as power meters.  If you set up your UHF antenna with a 3-foot truck-stop CB jumper going into your meter, then you are likely WAY out of 'whack'. These rules still apply at HF also.  It isn't as critical below 30 MHz since the wavelength is so long, but if you use a 4 or 5 foot long meter jumper at CB frequencies, it WILL be wrong. At 27.205 MHz, use a 6 inch jumper, or else a 9.6 foot one for accuracy.
 
Tech hint: I keep several different lengths of pre-made jumpers in my Bird watt meter case for different frequency bands that I normally work with, and have them all tagged as to what band range they are for.  The higher you go in frequency, the more critical this gets, and the SHORTER they get... sometimes TOO short, thus for 950 MHz, I keep a 15.6 inch jumper of LMR-400, which is 1.5 Wavelengths, but still on a calculated half-wavelength point in the line.  A 5.2 inch long LMR-400 jumper is too short to work with.
 
Long winded, sorry, but I hope this helps.
 
-Jones

Is that rise between your town house and ranch? If so, that might be a problem, but likely not.
 
I can get 15 miles from base to mobile anytime in the flat lands of southern Nebraska, so I doubt it will be a problem for you.
 
Installing a repeater on the high ground at your ranch would be ideal, since the base in town would easily bounce off that, and so could your family members working out on the ranch with handhelds.  Even non-family workers could use it, as long as they have individual GRMS licenses.
 
MTX 400 is a good radio, but don't use the cheap antenna they come packaged with.  Use high-quality antennas and coax cable.  Also, don't use the cigar-lighter plugs they come with.  Wire them up correctly, permanent installation style, and use a suitably rated power supply for the base.
 
On the mobile, (I assume pickup truck) drill a hole, and use an NMO mount antenna on the roof, as close to center as practical.  Don't skimp with a mag mount, or try to use an antenna mounted on the front fender, or you will be disappointed.  In my professional experience, a quarter wave on the roof, (which at UHF is about 6 inches tall) will out-perform a high-gain co-linear antenna on the front fender any day.

My family uses unit numbers, but not very often. Names work just as good.
 
In my family; my wife and I, and our oldest son are all hams.  Our 2 younger sons are not hams. (yet)
 
What's funny is that our youngest son takes this GMRS identification business more seriously than any of the rest of us.  I will call him on GMRS as: "Hey Mike, it's Dad, copy?"  He will respond with: "This is WQYM-Five Four One, unit 5 to unit 1, go ahead Dad."

You can listen to, and record any open, in-the-clear radio transmissions you would like, (except cellular phone and encrypted comms) and you may forward the recordings along with other documentation as evidence of violations to authorities.
 
If you are a repeater owner or trustee, then record away, it is your system to control. 
...and keep very good logs and notes, including time and date of alleged violations, and any triangulation or location info you have.
 
Make sure you have facts. Just saying "I think Billy is kerchunking my machine." will get you no where.
 
Also... one thing I have done on one my Ham machines to eliminate kerchunkers is to have ZERO hang time, and no "courtesy tone" or "Roger Beep".  The repeater works, but if they chunk-chunk-chunk it and don't hear the "tail", they assume it isn't working, or that they do not have the correct tone, and they leave.  If they key up and ID themselves, then I will answer.  I inform them about the machine having no hang time, and no beeps and boops.  I tell them it is like a "religious" repeater: they just need to have faith that it is working.

You can listen to, and record any open, in-the-clear radio transmissions you would like, (except cellular phone and encrypted comms) and you may forward the recordings along with other documentation as evidence of violations to authorities.
 
If you are a repeater owner or trustee, then record away, it is your system to control. 
...and keep very good logs and notes, including time and date of alleged violations, and any triangulation or location info you have.
 
Make sure you have facts. Just saying "I think Billy is kerchunking my machine." will get you no where.
 
Also... one thing I have done on one my Ham machines to eliminate kerchunkers is to have ZERO hang time, and no "courtesy tone" or "Roger Beep".  The repeater works, but if they chunk-chunk-chunk it and don't hear the "tail", they assume it isn't working, or that they do not have the correct tone, and they leave.  If they key up and ID themselves, then I will answer.  I inform them about the machine having no hang time, and no beeps and boops.  I tell them it is like a "religious" repeater: they just need to have faith that it is working.

You can listen to, and record any open, in-the-clear radio transmissions you would like, (except cellular phone and encrypted comms) and you may forward the recordings along with other documentation as evidence of violations to authorities.
 
If you are a repeater owner or trustee, then record away, it is your system to control. 
...and keep very good logs and notes, including time and date of alleged violations, and any triangulation or location info you have.
 
Make sure you have facts. Just saying "I think Billy is kerchunking my machine." will get you no where.
 
Also... one thing I have done on one my Ham machines to eliminate kerchunkers is to have ZERO hang time, and no "courtesy tone" or "Roger Beep".  The repeater works, but if they chunk-chunk-chunk it and don't hear the "tail", they assume it isn't working, or that they do not have the correct tone, and they leave.  If they key up and ID themselves, then I will answer.  I inform them about the machine having no hang time, and no beeps and boops.  I tell them it is like a "religious" repeater: they just need to have faith that it is working.

Note for clarity...
 
Vertex is NOT Motorola.  The EVX line is (was) Motorola TRBO compatible, but Vertex is a Yaesu product, along with Standard.... ie, Vertex/Standard.
 
Also note: Any form of digital modulation such as TRBO or P-25 is not allowed on GMRS.  These radios will have to be programmed in analog-only mode for use here.
 
-EDIT:
WOOPS, I stand corrected:
 
December 28, 2011 -
Motorola Solutions is taking full ownership of the Vertex Standard LMR business. The effective date for the reorganization will be Jan. 1, 2012.
Jun Hasegawa, president and CEO of Vertex Standard, announced the corporate reorganization. “After four years of joint venture with Motorola, we have decided to transfer the Vertex Standard LMR business to Motorola and focus on Amateur, Marine and Air-band business,” he said in a letter to customers.
 
 
October 16, 2017 -
Motorola Solutions said it will combine the best of Vertex Standard's portfolio with its two-way radio product lines beginning Jan. 1, and all products will carry the Motorola Solutions brand.
Specifically, Motorola will rebrand the Vertex Standard entry-level radios as Motorola products. The radios, most of which are analog or Digital Mobile Radio (DMR), will keep their current model numbers.
Vertex DMR radios will not be rebranded as MOTOTRBO, Motorola’s DMR product line. The Vertex DMR radios are compatible with MOTOTRBO, but it is a higher tier portfolio, said Mike Petersen, Vertex Standard director and general manager.
“We’ve worked to have closer alignment over recent years,” Petersen said. “It’s a natural progression that stemmed from a lot of internal collaboration. Both businesses are doing well, but this just allowed us to better align and serve our customers.”
Vertex will continue to offer a few select models in specific markets under the Vertex Standard brand. Petersen said the VX1700, an analog single sideband radio, is one example.
 
--
 
I guess I was a bit behind the times in this area.

PB30X, I cant say I have ever heard a message go over 30 seconds where I am. I believe the W2NJR system will even reset if the message is over 45 as a default because it ties up repeaters across the state of NJ. I did laugh at the use of judgement comment lol. Seems like the world is lacking in common sense and logic. Quite scary when one thinks about it.
 
Jones, thanks for the added info, and I hope my post didn't scare you about using EAS on the repeater, I was more curious and I cant think of any repeaters or systems that use them locally for GMRS. Now that I learned the EAS alert tone is FSK data I am curious what info FLDigi would spit out when decoding it. Off I go to do more research!

Strange this topic came up because I was wandering the same thing about a year ago and was never used. I have my Arcom programmed with DVR preprogrammed severe weather alert messages to seek shelter for incoming weather.. Through personal experience and Emergencies I would think they would turn a check as it is An emergency Alert (Grave Danger esp in the Tornado alley) As mentioned Rules are Rules, but I don’t think a DVR message is considered illegal broadcasting so long as you stay in Talk Guidlines parameters! Interesting!! I would think that allot and most alerts are long winded, and in most cases I believe over 2 minutes.. Either way, I would practice Good Judgement and flick the switch, it’s Not a live broadcast I do however have Garmin Rino radios with weather alert built right in, and came handy several times out and about. Especially in remote areas where cell coverage is NOT AVAILABLE!
 
Who Knows, May Save Lives, including AMBER ALERTS just an FYI, I am of Sound mind and use judgement when others FAIL TOO Someone has to, Good or Bad it’s called Responsible for Your own Actions.. Good Day!!

This is a very interesting topic.  I have disabled my EAS relay system until I get an answer.
 
As for the laws on use of EAS, it doesn't violate any of them.  It isn't a misuse of EAS tones, since these are real alerts, issued by authorities, broadcast for public consumption, and are simply being relayed as-is, without editing or modification.  I am not an authority, nor a PEP broadcaster, just an EAS participant; so I do not generate any of my own local alerts, just relay.
 
Obviously, if I were sending out EAS tones to tell the boys it's time for dinner, or sending zombie apocalypse messages, that would be a gross violation... but I do think weather warnings and AMBER alerts are important public information, and many times, the EAS relay message comes 5-20 minutes sooner than the same message from our cell phone providers.  Here in tornado alley, sooner is better.  We could get this same information using a NOAA weather alert radio, but that would be one more device for everyone to carry around.
 
Alerts from the National Weather Service are considered to be re-transmittable for public service.  All broadcast stations and cable systems are allowed to re-transmit NOAA weather radio audio, but many don't since it sounds bad on the air.... they have their own announcers/DJs read the weather.
 
As for identification: My call sign is embedded in the EAS tones as a participating relay, as required by the rules of EAS.  Immediately after an alert has been relayed, (and after ANY transmission has been over for 10 minutes) my controller has a synth voice that gives my station ID in English. (For those familiar, I run a CAT-400.)

So, the other day I was listening to the W2NJR ham radio network and heard an alert go out with an electronic statement "Thunder Storm Warning."
 
Basically, the W2NJR system uses the NOAA SAME code for the area to get weather alert and warnings. It then re-transmits the information following the coded signal, which is how the system knows what warning it is giving. This is legal on ham radio but what about GMRS? I am not planning on adding this feature to my repeater but if its legal I would think other systems could make use of it. The idea has just made me curious.

For those interested, the link to bluemax49ers' Ebay shop is https://www.ebay.com/usr/bluemax49ers

+1 for bluemax49ers on EBay. I've got a couple of his cables and they work flawlessly. His prices are very fair, too.
 
On the subject of cables, I purchased a CDM serial cable from RF Guys years ago. It has always worked well but knowing what I know now about the market, IMHO they are a tad overpriced. The one I have from bluemax49ers is of equal quality and performs just as well.

Since this discussion of used GMRS equipment is a topic drift from the original antenna topic of this thread. I have created a new topic to continue the equipment discussion... if there is interest.

The inability of Midland radios to do split tones is why I will never buy one At their current price point for the 40W mobile, they really ought to..

i do have an update on the antenna, but it's not a "final" configuration yet! i got my hands on a Laird no-ground plane antenna and did some comparison testing. in my opinion, it's slightly better than the Midland - but not by very much. i'll explain...
 the midland is sold as "pre-tuned to 462 mhz". the laird is ufh 450-470 - it's tuned to 450, and to better tune to 462 i should cut it a bit shorter. i've been afraid to do that - fearing that if i cut too much off, i could make things worse. right now my SWR is exactly 1:1 - i'm assuming because the anteanna is slightly longer than ideal for this frequency. but before cuting / tuning, i wanted to test it as-is. so i road tested the laird and compared to the midland. the first thing i noticed was the laird no-ground plane definitely had more "reach" than the midland, by a few blocks. maybe about half a mile to a mile farther. so i drove in and out of where i thought the range would end, and noted on a map where coverage was good, bad (meaning no receieve either direction), or staticy (receive but with static).where the range ended wasn't a hard cut-off. i found spotty areas just a bit father away that worked pretty decent. but overall, i was happy with the no-ground plane antenna being that it might have little better "reach" plus the spotty areas.i then retested with the midland anteanna, driving the same route. this time the midland performed better than my test a few weeks ago, and i also noticed more spotty areas where i had signal but didn't expect to. so the midland was better this time than last time, but still not as good as the no-ground plane. i think the different results with the midland were just more thorough testing and different topography / weather.in my test results, there were some spots that the laird worked and the midland didn't, and others that the midland worked and the laird didn't... but overall it seemed the laird worked better. i probably need a few more days to know for sure... but i guess that indicates there's not a huge difference. the mxt275 also came with a mag-mount antenna. i road-tested that one also, having it sit on the very top of my tire carrier (where i'm thinking to move my mount to). it performed better than i expected. within a mile it sounded crystal clear, but after about 1 - 1.25 miles it cut out pretty hard. really makes me wonder how a 1/4 wave would perform mounted at that point - one day i will try that, but might take a few weeks for me to find all the parts i need and to make sure i have enough coax. i found something else interesting with the two midland (mxt275 versus handheld gxt1000).if i configure a PL tone on a channel (which is applied to tx and rx) and run channel-scan, it stops at a channel that has signal, and operates as carrier squelch. if i change to that channel manually, with PL set, I don't hear anything. but as soon as i scan, it'll stop and that channel and i hear the transmission. i was surprised at this - and tested it again using my handheld with no PL configured. the mobile 275 stopped and i could hear it (only in scan, not when just sitting on that channel).i did the same test using the handheld as the receiver, with a PL set on the handheld, using the mobile to transmit with no PL. when the handheld is in scan mode and i transmit with no tone, the handheld stops at that channel, but i still hear no audio. so it more "pauses" the scan until there's no signal, then it moves on.i just thought that was odd, especially on the mobile.... but admittedly, i probably should check the manual, but it was more fun to just try it.

berkinet - thanks for your intense googling. i searched also, but didn't find anything.
 
Hans - i agree (to ask Midland for this). i've seen their post on their product site saying they're considering it... i'll try to contant them as well, at least to show there's more interest.
 
Jones - the monitor function on the mxt275 basically turns off squelch completely, outputting (very loud) static until someone transmits.

Just for clarification, the FCC didn't cite the Baofeng company or any manufacturer of Baofeng radios.  This action applies to one specific distributor, Amcrest Industries LLC d.b.a. Baofengradio.us.  All they have to do is stop selling this radio within 30 days of the notice and they will face no monetary fine.  I think this matter will unfortunately not have an appreciable impact on the availability of Baofeng and other related radios here in the US, but I am glad to see any action taken at all around this issue.  It's definitely a step in the right direction.

I came across the North Shore Emergency Association's website recently and found their club history page interesting:
 
nsea.com/nseainfo.htm
 
This link briefly discusses how the "travel tone" of 141.3 Hz and the national calling/emergency frequency of 462.675 MHz came to be. NSEA was one of the very first adopters of GMRS in the early 1970s, then the Class "A" Citizens Band. Here's a quick snippet from the link:
 
NSEA members were instrumental in bringing UHF technology to other public service groups in CB, especially R.E.A.C.T. (Radio Emergency Associated Citizens Teams). Beginning in 1976 key NSEA members spent extensive time meeting with REACT teams in more than a dozen-and-a-half different states, bringing a portable repeater, together with a number of mobile and portable units for field demonstrations...As a result, over 200 personal use repeater systems (all on the same frequency [462.675 MHz]) were set up throughout the United States. In recognition of this trend of explosive growth the Federal Communications Commission formally recognized our frequency [462.675 MHz] as the national emergency and traveler's assistance channel in the Part 95A Rules and Regulations.
 
Pretty cool slice of radio history!

Roof vs headache rack will make a difference.  For a 1/4 wave antenna to work properly, you need sufficient ground plane; the center of the roof is where you would want to mount this antenna.  If you prefer to mount an antenna on the headache rack, use a 1/2 wave antenna which does not require a ground plane.