Logan5

Radioguy7268,
 
I'm in Brooklyn very south and east, no buildings just houses, by the water... Very little rf interference. The only uhf rf 70cm is the nypd / fire / ems repeaters on a couple of telephone poles and vhf from Airplanes, Kennedy Airport and marine channels.  People don't even have driveway door remotes.... Nearest cell tower is 1 mile. But lots of above the ground electrical wire on telephone poles.... We have about 3 gmrs repeaters and 5 ham 70cm repeaters. But Brooklyn is huge... We can fit 2 1/2 London's or Berlin and France together inside Brooklyn..The repeaters are all spaced far apart. It's not like Manhattan at all. We have a saying in Brooklyn - Keep Brooklyn low and local.... No tall buildings and no Wal-Mart.
My antenna is 45ft high. which is 20 ft over my house. Only a couple of drive thru about 3 miles away that broadcast on .5 watts murs. Just mom and pop stores that most don't even take debit card..... I'm in the sticks of Jamaica Bay...I'm by a 25 square mile national park made up of wetlands sparse trees.
I work in Manhattan and can hit my repeater 20 air miles from the 28 floor roof deck my friend is the super of...5 watt hand held. 

The repeater antenna I recommended, the DB404-B has a gain of 5.9dBi, with no beam tilt.  That is a great antenna to use if you have it high in the air, and height always out-performs antenna gain.
 
A 10dBi gain antenna at 30 feet will do well in a situation like this, but won't have the range of a 5dBi antenna at twice the height.
 
One must also keep in mind that antenna gain comes as a compromise.  To make gain, the antenna must have a narrow beam-width... as in the antenna system is designed to pull the energy up off the ground, and down out of the sky, focusing it into the horizon.  If you have a high-gain antenna on a tall tower, it will have great distance range, but will also provide very poor results up close to the tower site.  The signal will simply over-shoot the target radio.
 
Real world case:  I take care of a UHF Ham repeater in Campbell Nebraska on 444.475/449.475.  It is using a DB420, which has 11.3dBi gain, and it is mounted at about 290 feet on a commercial tower.  Other repeaters link into this site from well over 40 miles away.  I live 7 miles away from this site, and can use a 2-Watt handheld from my back yard just fine.  If I travel closer to the machine, I drop in and out, and can no longer hold the machine when I'm 1-3 miles away, due to no ground coverage, and signal overshoot.  I'm inside the shadow ring of the antenna system.
 
Summary: Use a higher elevation, and a not-quite-so-high gain antenna for a project like this ranch.  The lower gain antenna will have much better ground coverage near the tower site, without shadow rings around the site, and the height will make up the distance covered.

199.9  feet unless you are within an FAA flight pattern for a local airport. See 47 CFR 95.317 for details and current restrictions.

https://www.ecfr.gov/cgi-bin/text-idx?SID=72b61b708f0ce25ea78b21b0aed4e95b&node=47:5.0.1.1.5&rgn=div5

 

I've been trying to decide about GMRS for about a year now. I have two ranches in West Texas that are about 6 1/2 miles apart and in many areas cell phone is not reliable. I've had my ham license, but I can't legally use ham to conduct our family ranch activities.
 
I would also like to be able to communicate with my home in town which is about 9.5 miles.  I'm pretty sure I can't do this with just handhelds, but I plan to use the Midland MXT400 in by truck and set up a base at my home in town with another MXT400.  With my house being at least 20 ft high, I should be able to get an antennae around 40 ft. 
 
I've checked elevation on google earth, and my ranch has an elevation of approximately 80 ft higher than town (only 40 ft if the antenna is 40 ft), but there is a rise/hill about 10 feet higher that is about 1.5 miles from the ranch. Since I don't really have a lot of experience with UHF, I was wondering if it was likely that reliable communication would be possible between the mobile and base, with the base having a 40 ft antenna.
 
Ultimately, I'm thinking about putting a repeater at the ranch, which would allow a 40 ft antennae (20 ft. over existing structure) at that location. 
 
Any comments would be welcome.
 
Thanks - Karl

Found this... http://www.opg.org/wp-content/uploads/2016/08/IMG_20160826_115553.jpg
 
on this site... http://www.opg.org/2016/08/26/wln-kd-c1-the-programmable-toy-radio/

How can you just leave us all hanging, what was the outcome?

I bought a pair of the TR-505s to give to my (grown up) children. I put in the 'mid power' GMRS channels, and our local NOAA weather channels. If you tab into the TX frequency column and hit the delete key to erase the numbers, transmit is disabled.

How high is the antenna? Is the antenna resonant on the freq? What type of cable, how long is the cable run to the antenna, did you hook the duplexer up backwards?
 
I am guessing TX and RX on duplexer us backwards, try swapping your cables.
 
Corey

I have one of the new Bridgecom VHF repeaters, 2 of the older Bridgecom VHF repeaters, and 2 of the older UHF repeaters on the W0WWV Link System in Nebraska.  It is a Ham system, but the repeaters are the same, and I have had good service from them for years.  On the oldest ones, I did have to replace the power supply capacitors after about 5 years of 24/7 service. 
 
No, I don't have any financial interest in Bridgecom, but I do use them, and can recommend them.  They aren't Motorola, but you're not paying for that name either.  As near as I can tell, they use Maxon commercial internal components.
 
The company does have outstanding service, and the techs answer their own phone calls when you have questions.
 
I do not know who makes their duplexers.  I use Sinclair, dB Systems, and Phelps-Dodge duplexers.
 
-Bart

Happy Birthday shout out to Logan5

This is an old post, but we solved our problem like this:
It took days using Kenwood TM-V71a radios on reverse but we finally caught our offender. Looking in his car he had an old Maxtrac. We obtained his name from a neighbor. After that, anytime the crap would start, we would reply something nice and thank John Doe at 123 Cedar Street and say nothing more. He was furious and went into cuss fits, but after only 2 days we never heard him again.

My personal view is that there should be NO automatic data bursts for GPS tracking. I really don't see what constantly transmitting your location would be useful for. I would think that if you do want your GPS location to be transmitted, it could be sent like an ID burst upon pressing the PTT. I believe that by doing this it would not only keep the air clear from constant data chunks being sent, but also extend battery life as the radio wont be auto transmitting for two and a half minutes or receiving & decoding two and a half minutes per radio in use every hour. This allows users to update their location either through check-in or through general conversation and could even be used on a repeater as it only sends the data burst when the user is talking.

Here's my letter acknowledging the meeting with the FCC, per their request, to keep a record of the communication:
 
https://ecfsapi.fcc.gov/file/1060628686973/FCC-Letter-2018-06-06.pdf
 
We'll be drafting a reply to the petition shortly.

For checking antennas, I use a Bird 43 THRULINE directional Watt meter with the frequency-correct insert slug for whatever band I am testing.  But then, I do this kind of work professionally.  These meters are very nice, but a bit out of price range for the typical radio enthusiast. a new Bird 43 will set you back about $350, and the slugs run from $100 to $300 a piece, depending on power level and frequency range.
 
...and they don't read SWR.  They read forward, and reflected power in Watts.  You then have to do the math to figure out the Standing Wave Ratio (SWR). (There's an APP for that)

To all GMRS licensees:
 
I have just spoken with the FCC regarding a Petition for Reconsideration filed by Motorola regarding automatic GPS and data transmissions on the GMRS band.
 
Motorola would like to allow automatic transmissions on the 462 MHz frequencies which includes repeater outputs (Channel 15-22) and the interstitial 462 MHz channels (Channels 1-7). The repeater inputs are not presently mentioned, however we will articulate our position to the Commission that these input frequencies should be prohibited due to the potential of interference to repeaters.
 
myGMRS.com (and it's parent company RepeaterFinder, LLC) will be filing an ex parte response in the docket with the following requests:
 
A Busy Channel Lockout (BCL) feature be mandated for any radios which are to operate in an automatic fashion. The devices must inhibit transmission if there is co-channel activity to prevent interference to other users of the shared frequencies. Blind periodic transmissions are going to be very problematic and will almost certainly cause interference.
  Limit automatic transmission to the 462 MHz GMRS channels only. Repeater inputs must be excluded to mitigate potential interference.
  Duty cycle limits of the bursts must be set by the FCC. I believe Uniden America proposed no more than once every 2 minutes and no more than 5 seconds per transmission. This sounds reasonable to cover longer text messages and location updates without constantly trashing the band.  
The FCC plans to respond to Motorola and issue a decision in the next couple of weeks, so anyone who would like to submit comments to the record is encouraged to do so as soon as possible. No exact deadline was given, but they expressed a desire to have this hammered out within the next week or two.
 
I will provide further details later today.
 
Original Petition for Reconsideration from September 2017:  https://ecfsapi.fcc.gov/file/10928247080350/Ready%20For%20Filing_Motorola%20Part%2095%20Petition%20for%20Recon.pdf
Further Comments from Motorola from January 2018: https://ecfsapi.fcc.gov/file/101081822912433/Motorola_Part%2095%20Recon_Further%20Comments.pdf
Letter from Motorola Detailing their Discussion with Members of the FCC from April 2018: https://ecfsapi.fcc.gov/file/10420845023222/April%202018_GMRS_FRS_ex%20parte%20notification.docx
 

Any tunable antenna should have come with a cutting chart that shows how long the whip should be for a given frequency.  Check the chart, measure it, and cut it off to the correct length.  If you do not plan on using repeaters, then set the antenna length for 462.600 MHz.  If you plan on using repeaters also, then you might want to split the difference, and set the antenna tuning for 465.000 MHz.  That should give you good coverage for the GMRS band.
 
If you want to get picky, and actually check and set the SWR, then the first thing you need is an SWR meter that will work on UHF frequencies. The typical cheap CB type SWR meter will not work at UHF.  To get an accurate reading, you must also use a 1/2 wavelength cable going into your SWR meter.  This is frequency dependent, will vary depending a cable velocity factor, and IS critical.
 
NOW... All that being said, With your UT-72, I believe you have a fixed, non-tunable antenna.  It doesn't look like you can set the SWR on it.  It is just a quarter-wave whip on 2 Meters, and will function as a 3/4 or 5/8 wave on 440.  Either way you look at it, it isn't going to be much good on GMRS, as from what I can see, it is a Ham-band antenna.

A few days after I returned from my annual visit to the "Holy Shrine of Hamdom" (Dayton Hamvention) I received a mysterious email notifying that a package was being sent from Ohio via FedEx. I was a bit suspicious since I knew I hadn't ordered anything. Then I thought maybe DARA (Dayton Amateur Radio Club) was sending me a polo or tee-shirt as a thank you for my weekend of volunteer work as a shuttle driver.
 
But then, I noticed that the package weighed 2.5 pounds, and a signature was required, so just what was it?
 
When it was delivered a few days later, I briefly noticed that the edge of the box had "JCVKenwood" printed. Now my curiosity was truly aroused!
 
It turns out that unbeknownst to me, I had won one of the major show prizes in the hourly ticket drawing! It was a brand new, shiny Kenwood TH-D74 Tri-Band HT!  Shoot, the thing will also receive AM, FM, SSB and CW. Every thing pretty much from DC to Daylight no less. MSRP for this HT is $585 USD, and the currently lowest price is $506 at Amazon.com
 
While it was indeed a very pleasant surprise, having played with it a bit, read the manual, and watched quite a few YouHooTube videos, I'm come to the conclusion that it has several drawbacks, at least from my point of view.
It's way too complicated with nearly 1,000 menu options. Its programming software is more complex than any DMR radio I've ever seen, and that includes Motorola. It's digital mode is D-Star, not DMR. As there are only two D-Stars in Chicago, they are way out of range of an HT in Northwest Indiana. It is completely useless for GMRS since it will only Rx on those frequencies, Tx is inhibit and cannot be modified, except for the traditional MARS/CAP expansion! I first thought I'd sell it, but by the time PayPal and eBay extorted their share of the proceeds, I would probably only net around $400 or so...
 
For these reasons I've decided to donate this to my local ham radio club to be used as a Grand Prize in a future raffle. At least this way the club will benefit, and we can use the proceeds for our STEM projects to encourage youth in their education, and perhaps gain a few new youngsters into becoming amateur operators.
 
 
 

I have been lurking in background for a while, finally joined today. I have read that my family can use my liscence. Does this mean household or son that has his own home.
 
I enjoy reading the info

My name is Pat, callsign WRAR990. I became a licensed GMRS Operator on February 13th, 2018. I am part of a local auto recovery team, all volunteers, who pull vehicles out of snowbanks & ditches for free of charge, and some of us are licensed GMRS operators. I'm also a volunteer firefighter here in Western NY.

always good to have a reference
cable sweep of the SCOP antenna after the March storm.
distance to fault. distance vs SWR
http://i65.tinypic.com/258mmwg.jpg
return loss
http://i67.tinypic.com/wi50lu.jpg
distance to fault return loss
http://i65.tinypic.com/t9ytyo.jpg
 
 

Hey everyone,
 
So, I recently picked up a Kenwood TK880. I've heard quite a few good things about these radios, however when I powered it up for the first time, it displayed Ver: 1.5209, beeped, then showed yyyyyyy

From research, I learned this is likely a firmware issue in that it should be Ver2.xxxx as per the sticker, but was flashed to Ver 1.5xxx for passport use. Does anyone know how to obtain the FPro software and Ver2 firmware?

I have to say, the Tera is possible to be programmed to Emergency services too. I currently have one channel on my Tera 505 programmed to receive my local police radio. I programmed the transmit to a GMRS frequency to be safe though. 

It's Part 90 certified (somehow), which is better than no certification. CHIRP is the programming software to use. Regardless of whatever service you're operating on, you will want to turn off STE, RP-STE, and ROGER, and leave PTT-ID disabled, AL-MOD on SITE, and RPT-RL on OFF. Within CHIRP, you can disable transmit on a memory channel by setting its offset to "off", and that should be done for anything you don't have authorization to use (such as out-of-band frequencies and private repeaters).
 
All GMRS repeater channels have an offset of +5.0000 MHz, and a receive frequency between 462.550 and 462.725 MHz. Any other offset other than 0.0000 (simplex) or +5.0000 (repeater) can take you out-of-band, so it's important that you double-check your frequency entries on Part 90 radios.
 
Once you know which repeaters you want to add, check both their transmit and receive CTCSS/DCS settings. If transmit CTCSS/DCS is wrong, the repeater won't hear you; if receive CTCSS/DCS is wrong, you may be hitting the repeater but you won't hear it (the green light on top will still light up, but audio won't play unless you hit the monitor button).
 
If you've got it all loaded and you want to check if it's working, you can hop on a repeater, give your callsign, and ask for a radio check. Anyone else out listening will usually tell you how well they can hear you, and at a minimum you should hear the repeater's tail.

Using a properly mounted NMO places the antenna over a ground plane surface at a proper resonant distance and has a DC ground.  If a mag mount is used, the bottom of the antenna itself is above the ground plane surface by at least an inch and the resonant length of the antenna may be off.   It also has no DC ground connected to the vehicle body at that point because of paint layers, etc.

From personal experience - If an NMO body mounted antenna is cut to a resonant length for lowest possible SWR, and that same cut antenna is then placed on a mag mount, the SWR will be a bit higher.  If the antenna on a mag mount is then re-cut to compensate for the additional height of the mag mount above the vehicle body, the antenna will then be non resonant if placed back on a body mount NMO.

I have also found that most (but not all) NMO mag mounts have factory supplied coaxial cable and PL259 that are somewhat inferior to what might be used with an NMO body mount from a frequency sensitive and loss per foot aspect.  

I was looking online to see what I needed to listen to my local police. I use an Android scanner app that has some area police, but not mine. So I wanted to see what equipment I would need.
 
I found they are using 155.43. I realized that should be in the TR-505 range.   I decided to see if I could program that frequency into the Tera, and it accepted it along with the PL code. It picked up traffic just fine. I then went back and programed the transmit on that channel to a GMRS frequency to be safe in case someone keyed the mic. It is working great. Not the intended use for it, but it is nice to having to buy new equipment.