AdmiralCochrane

For those who do not know the URL: https://wireless2.fcc.gov/UlsApp/UlsSearch/searchLicense.jsp

They don't and primarily it has to do with specific absorption rate.   https://en.wikipedia.org/wiki/Specific_absorption_rate
 
The labs that certify this gear must ensure that your body does not get heated above a certain level when RF device is operated nearby. You might see a 6 watt VHF radio, but that is pretty much the limit.
 
an example cert.
 
https://fccid.io/AZ489FT7087/RF-Exposure-Info/SAR-Report-1-of-2-3054950

BINGO!!!!! BINGO!!!!! BINGO!!!!!
 
It is not the FCC GMRS specifications (at least as currently written) that explicitly limits the output power of a hand-held transceiver across the board. Max overall power for the handheld is ultimately limited by the ability of the transceiver-antenna system to achieve SAR compliance on the frequencies of operation.
 
For those reading this post that do not already know this, amateur radio operators are required to know how to calculate or have the ability to measure this for equipment they own and operate. They are legally required to make sure that safe SAR levels are maintained, which applies to family and the public.
 
Kudos WPXM352!
 
Michael
WRHS965
KE8PLM
 
 
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Select, copy, paste.  
 
Thanks G! 

Yes, absolutely, Lscott.
 
Equipment needed.
-RSSI meter. (Motorola radios have RSSI meters built in, make sure its calibrated, all XPR radios I own are within 0.5 dB of each other, so they are good for the sake of this test)
-Signal Generator (use a calibrated RSSI meter to ensure the signal on the display is correct, used the XPR radios here to measure)
-50 Ohm dummy load, I use a 50W one, but for the receiver sens test only you don't need anything more than 1W. (for duplexer desense you need the large one)
-ISO-tee (directional coupler)
 
Procedure:
1) If you don't have a directional coupler and you don't want to buy one, you can build your own ISO-tee using an old SO-239/PL-259 T-adapter. You need a hacksaw and a file. Unbolt the PL-259 prong from the T-adapter first, cut it with a hacksaw so it barely touches, and then, if needed, gently file it until the measured isolation is around 20-30 dBm. Remember the T adapter already has a 3dBm isolation, and it doesn't take much to file it a bit too much, so, be careful: I ruined two T adapters before getting it right... To measure the ISO-tee isolation I used the XPR6550 RSSI meter with the Signal Generator. You can also install a 20 dB attenuator on one end too I've been told... or you can just go and buy one from eBay... 
 
2) Measure the site RSSI with no signal, this is the lowest signal the radio will be able to hear, for that I used the XPR6550/7550e RSSI meter. This is the best the radio can do, if the noise threshold is -107 dBm, it will never be able to hear a -115 dBm signal... no matter what. You want the radio to be as close to this figure. Perform the ISO-tee tests on several locations to see how different noise thresholds affect receiver. Useful for mobile application. Noise threshold is not receiver desense. Desense happens in addition to the noise threshold.
 
3) Measured absolute receiver sensivitty and squelch sensitivity on the radio. 
-Set SQL to threshold.
-Connect SG to radio directly with lowest possible signal. -130 is usually a good number to start.
-Increase signal dBm until SQL opens. Record this number.
-Reduce signal dBm until SQL closes completely. Record this number.
-Keep reducing signal dBm until RX led is no longer blinking. Record this number.
 
4) Connect ISO-tee as follows:
-The vertical part of the T-adapter to the signal generator (the one you cut/filed).
-The horizontal ends one goes to the radio, the other one to a 50ohm dummy load.
 
5) Measure dummy load sensitivity.
-Set SG signal strength to lowest possible dBm.
-Increase signal dBm until SQL opens. Record this number.
-Reduce signal dBm until SQL closes completely. Record this number.
-Keep reducing signal dBm until RX led is no longer blinking. Record this number.
 
6) Replace dummy load with the antenna the radio uses and measure sensitivity again.
-Set SG signal strength to lowest possible dBm.
-Increase signal dBm until SQL opens. Record this number.
-Reduce signal dBm until SQL closes completely. Record this number.
-Keep reducing signal dBm until RX led is no longer blinking. Record this number.
 
7) Subtract the RX led sensitivity figure recorded in step #5 minus the RX led sensitivity recorded in 6.
 
8) Subtract the result calculated in step #7 from the figure recorded in step #3. That is your "effective sensitivity" which can vary quite a bit depending on location.
 
9) Subtract the result from #7 from the noise level, that will give you the desense relative to noise floor.
 
10) Now repeat step 7 8 and 9 this for the figures calculated for SQL open and close if you operate in FM, remember to set SQL to threshold, or lowest setting possible. For FM operation Squelch Performance is critical, so you will determine using this test if the radio needs its squelch aligned, tuned... etc. 
 
--You can also use this procedure to evaluate duplexer performance and see if you need additional isolation on the RX side if its desensed b/c the transmitter...etc.
 
Once I performed this test on enough of my radios I started to see an emerging pattern, a trend. After all radios were measured, most commercial gear radios I own measured a typical 3-4 dBm "desense" over the noise floor in nearly all my use case conditions, whereas nearly all CCR stuff had an average of -13 dBm desense, in VHF, and about -17 dBm desense average in UHF, again under typical use case conditions.
 
EDIT: Another trend I noticed was that for nearly all CCRs, the higher the antenna gain, the higher the desense above noise threshold, or a decrease in effective sensitivity. Using my base antenna as the ISO-tee antenna, a triple 5/8 collinear at 40 feet up, the desense measured on several CCRs was pretty bad, but honorable supersuck mention goes to all the TYT and Retevis CCR radios tested (GD77, RT52, RT82, TYT MD760) The desense over the noise floor (which was measured at -119 dBm) was on the order of -38 dBm in VHF, and -43 in UHF... so all that gain that my base antenna, all 4.5 dBb, were demolished by the massive -43 dB desense coming from the CCR landfill of garbage... A total winner in my book to buy these pieces of garbage. With the GD77/RT52/RT82/MD760 the base antenna I couldn't hear a 50W mobile beyond 2 miles. With an EVX-539 portable mated to the same antenna I could hear the same mobile, on 25W, talking from 17 miles away. Again, same antenna.
 
 
G.
 
 

The 5.5 dB claim is, simply put, not true. (also, if you don't see dBd or dBi its probably fake as well) That TRAM1173 (or MXT26) antenna probably has less gain than a simple 1/4 wave NMO, given the cheap coils used, and being only 2 elements, with insufficient phasing element separation between them (gain in collinear antennas is achieved by increasing the distance between the phased elements) not a chance in he11 it has 5.5 dBd... well, unless decibels dBs overseas are measured differently than in the rest of the world... that is.
 
For comparison, a real world 5.5dBd gain is what a 4-bay folded dipole has, which is a massive antenna, and coincidentally, it costs a lot of $$$$$...  too.
 
IMO, and in my experience, for a car install, a simple 6" inch NMO antenna cut to GMRS frequency will work absolutely great, as measured.
 
G.

I currently think the sweet spot for memories on a GMRS-specific radio is somewhere between 64-128 for the power user; one that travels regularly to different cities and uses the radio in each. Perhaps 32-48 is probably more than sufficient for the average GMRS user. 30 is too few.
 
Michael
WHRS965
KE8PLM

It is the limited number of channels on GMRS that makes multiple places to put the same frequency with different PL/DPLs even more important. 
 
I find it very frustrating to have to manually re-program my radio just to change PLs.  If the channel I use at home uses GRMS 7 with PL 162.2 but a jeep group I sometimes ride with uses GMRS 7 with another PL then I have to stop on my trip up north to re-program the different PL.  
 
I think it is the thousands of channels (frequency plus PL/DPL) available on GMRS that gives GMRS such a  powerful potential.
 
Kirk 
WRHS673

Messaged you about the Kenwood TH-F6a

GMRS would probably do what you want - and might be a really good fit, especially if you want to use hand held portables. GMRS runs on UHF frequencies - and you would not re-use your old VHF antenna(s) for GMRS.
 
If you're more interested in just having mounted radios in your vehicles, then VHF might still be a good option. Pricing for VHF vs UHF/GMRS radios would be comparable. The cost of a Repeater for UHF/GMRS would probably double the overall cost of your system.
 
I think that you should probably try to get some local help - someone who knows radios and could take a look at what you've got, and ask the right questions about what you want to accomplish, and give you some ideas of what might fit your budget.
 
Someone else will probably bring it up - but GMRS licenses run "per family" - ie: One license covers one set of relatives. If it's a family farm, it's pretty simple. If you've got unrelated employees, then potentially you would need to license each of them individually.  A VHF or UHF commercial/business License would not have those limitations, but it is more expensive to set up a License for that type of operation with the FCC.
 
I've got a nephew with a family farm out in Indiana. He's running GMRS with a repeater up in the barn, and he gets a good 3-5 miles with portables - even further with his mobiles.

Up for your consideration...
 
Pictures upon request... Prices are all negotiable, you can PM me for programming for the Motorola/Vertex radios.
 
Please, ask if you don't see something listed on the descriptions. If you feel something should've been included, or its missing then PM me, please.
 
Also, radios are listed locally and other internet sites as well, but I'll try my best to keep this list updated.
 
Two options:
->Local pickup, cash only. I live in the Madison, WI area.
->Shipping to CONUS only, PayPal gift.
 
Inventory for sale.
x1 - Motorola XPR6550 portable, VHF only (136-174)(GPS) Excellent condition. Battery, antenna and M charger.  $195 local pickup. $205 shipped.
x1 - Motorola XPR6550 portable, VHF only (136-174)(GPS) Excellent condition. Battery, antenna and VS charger.  $185 local pickup. $195 shipped.
x1 - Motorola XPR6550 portable, VHF only (136-174)(GPS) Excellent condition. Battery, antenna and VS charger.  $185 local pickup. $195 shipped.
 
x1 - Anytone AT-578U/V mobile, tri-band: 140-220-440, DMR/FM (GPS), upgraded with trimetal N connector. Excellent condition. Microphone, GPS antenna, mounting bracket. $350 local pickup, $360 shipped. AES encryption capable.
 
x1 - TYT UV-8000E portable, UV, FM w/crossband repeat. Excellent condition. Same as new items included. Box, charger, cable, antenna, etc. $50 local pickup,  $55 shipped 
 
x1 - Alinco DJ-MD5TGP portable, UV, DMR/FM (GPS), Excellent condition. Comes with everything as new. PLUS a shoulder microphone. $140 local. pickup, $150 shipped. 
 
x1 - Alinco DJ-MD5TGP portable, UV, DMR/FM (GPS), Excellent condition. Comes everything as new PLUS a spare battery and a shoulder microphone. $170 local. pickup, $180 shipped. 
 
SOLD  x1 - Vertex Standard EVX-531 portable, V only, DMR/FM no display. Excellent condition. $80 local pickup, $85 shipped. AES encryption capable
SOLD x1 - Kenwood TH-F6a portable. all band all mode w/SSB receive, 144-220-440 transmit. Mars-cap enabled, in Good condition, missing the PTT paddle and the microphone rubber cover, clean screen. Comes w/antenna and battery.  $150 local pickup, $160 shipped.
SOLD x2 - Radioditty GD77 portable, UV, DMR/FM. $80 local pickup, $85 shipped. Excellent condition. Chargers, UHF Vertex Standard antenna, 1 programming cable.
SOLD x1 - Motorola XPR6550 portable, UHF only (400-470)(GPS) Excellent condition. Battery and antenna only. $130 local pickup. $140 shipped.
SOLD x1 - Motorola XPR6550 portable, UHF only (450-512)(GPS) Excellent condition. Battery and antenna only. $130 local pickup. $140 shipped.
 
G.

I'm In, thanks!

The KG-805G is certified for transmit on GMRS only. It is receive capable on a notable chunk of 400MHz band.
 
Michael
WRHS965
KE8PLM
 
 
Sent from my iPad using Tapatalk

Well there's a new mobile coming out. Reviews on the model its based on are very good.
https://www.buytwowayradios.com/wouxun-kg-1000g.html?___SID=U
I also read some talk about an MXT400 II. Nothing solid.
 
 
I returned my MXT400 and MXT275 before the return policy expired. Really wish that the MXT275 was WB, everyone noticed the lower RX audio.
I also have the BTECH GMRS-v1. I missed the return date. Oh well, its the loner , if needed.
Due to the fact that you can only RX on teh first 30, I didn't even want to try the GMRS-50x1.
 
I have and mainly travel with the Wouxun KG-805G.
I have about 20-25 saved channels.  3 or so the same Freq, and 2 with split tones.
With the Wouxun having a SuperHet, you can hear the difference side by side on the cleaner received signal.
Trying out the 805G with a KVG VR-P25, 20-30 Watt Digital Amp.  I'm getting the full 30Watts.
Just need to see what kind of receive I get when traveling.
 
Also waiting for the to be released/certified:
https://bettersaferadio.com/bsr-wouxun-kg-uv9g-gmrs-two-way-radio-scanner/
I played with my buddy's KG-UV9P, feels and operates very solidly.
 
Just my limited experience and .02 cents.
 
 
Maybe sometime int he future move to an Icom or Kenwood.
I don't know much about which models are OK for GMRS.
8-)

Another option I've found to be a good compromise is to remove the sharkfin/oem antenna on the roof and install the NMO mount there. I've relocated the sharkfin internal components to the spoiler or to the third tail light on my cars. Saves the hole drilling dilemma, its easily reversible and no more scratching paint magmount shenanigans, or any other magmount issues. Works sufficiently well, although its a little less optimal than drilling the hole in the dead center of the roof... but my cars/vans have large panoramic sunroofs so makes it quite impossible to drill holes on a glass roof... so, the only place left is the OEM sharkfin location. UHF is not as bad as VHF, a 6 inch antenna is not even noticeable on a minivan.
 
G.

(ii) is the one you're thinking of related to ham equipment. the closed to ARRL i see is (iii) under a definition of "teaching"
 
§97.113   Prohibited transmissions. 
 
(3) Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer, with the following exceptions:
(i) A station licensee or station control operator may participate on behalf of an employer in an emergency preparedness or disaster readiness test or drill, limited to the duration and scope of such test or drill, and operational testing immediately prior to such test or drill. Tests or drills that are not government-sponsored are limited to a total time of one hour per week; except that no more than twice in any calendar year, they may be conducted for a period not to exceed 72 hours.
(ii) An amateur operator may notify other amateur operators of the availability for sale or trade of apparatus normally used in an amateur station, provided that such activity is not conducted on a regular basis.
(iii) A control operator may accept compensation as an incident of a teaching position during periods of time when an amateur station is used by that teacher as a part of classroom instruction at an educational institution.
(iv) The control operator of a club station may accept compensation for the periods of time when the station is transmitting telegraphy practice or information bulletins, provided that the station transmits such telegraphy practice and bulletins for at least 40 hours per week; schedules operations on at least six amateur service MF and HF bands using reasonable measures to maximize coverage; where the schedule of normal operating times and frequencies is published at least 30 days in advance of the actual transmissions; and where the control operator does not accept any direct or indirect compensation for any other service as a control operator.

20kHz per 95.1773.a
 
Michael
WRHS965
KE8PLM
 
 
Sent from my iPad using Tapatalk

I think it would be an excellent sticky to have at the top of the equipment review section

I see that I've many replies and should say thank you ALL for help and insight...
 
I got it to work on both of my test settings this afternoon with the repeater operator.  Family so happy on this family hobby.  Since BTWR was closed for the holiday.  I had to import radio factory setting using CHRIP software to see what was going on.  In doing so I saw via the programing software which showed it was not setup for +5 on duplexing.   Just a side note, being a newbie, I asked BTWR before purchasing if they would set up this first repeater channel for me.... BTWR reply NO.  I will say BTWR was helpful in getting me to pick this KG-805G and very help with it.  Now I'm open for any other HT I should be looking at as I only have this one plus an old FRS unit.
 
I hope I did not offend anyone with my repeated questions.  It is one of those things, where you have to ask enough folks as everyone see things from different points of view.  Sure I did not ask the right questions as I did not know what they where.  So asking gave me many answers to the puzzle piece I was missing.  You all played a part getting me to be successful in front of family and kids during the first radio check with repeater.  Must thankful for the PM answers these guys gave just the right on out of the view of others.  Be patience and helpful to us newbie as we are the future of GMRS...  
 
You guys have been a good witness to me and my kids of caring, helpful teachers, that what make you so great in my eyes... 
 
P.S. Now for any Newbie with Wouxun KG-805G GMRS Radio, feel free to call on me... I can be one of those puzzle piece you need for the question you have no clue how to ask it.  We will PM several times until we get it right thus not boring others on the forum.

When the radios were physically limited and you had to take them apart and physically remove a blocking diode it was clear that the manufacturer had actually manufactured the radio in compliance.  Compliant firmware is a major shortcut and shortcoming.

Your comment caused me to go back and re-read the rules to see if I could reach your conclusion. Instead I ended up again concluding that a part 95e radio cannot, under any circumstances, feature the ability to transmit on any frequency that is not a GMRS frequency and that said responsibility for this lies with the internals of the radio transmitter. In simple terms, nothing that the user can do from the exterior of the radio (via its control panel or via external software) shall enable to radio to transmit on any frequency that is not a GMRS frequency. I did not conclude that a VFO could not exist, but I do conclude the absence of a VFO in combination with the complete absence of external programming capability is a means to achieve compliance. 
Now, the reason that I do not conclude that the presence of a VFO button alone makes the radio ineligible for part 95e compliance is basically this. In order for a multi-channel GMRS radio to be useful there needs to be a means to switch between authorized frequencies. Channels are one means of doing this. A channel is however, at its essence, a radio preset that maps one or more big numbers (frequencies and settings) to a short, more-easy-to-remember, number. This equates to a radio memory. A VFO at its essence can do the same thing, but instead it enables the user to choose the frequency and other settings through direct entry.
 
The VFO violates FCC intent if (in my opinion), by means of using the VFO, the radio suddenly has the ability to transmit on frequencies that are not allowed. But, this is where the radio internals come in. While the user may be able to tune to and receive signals from many different frequencies, it is the internals of the radio that are responsible ensuring transmissions occur only on authorized frequencies (frequencies for which it is certified).
 
By case and point. I own a particular amateur HT. The radio is only permitted to transmit on amateur frequencies, yet is is capable of receive on 10s of thousands of frequencies. The radio features both VFO and channel selectors. However, any attempt to Tx on a frequency outside the amateur radio allocations, whether by VFO or by channel selector, is blocked and both a tone and message are presented to the user.
 
My conclusion therefore is that VFO can exist on a part 95e radio, but the radio shall not have the ability to transmit on any frequency that is not a GMRS frequency.
 
For those that wish to read more, refer to Part 95.1761. And here is an excerpt from paragraph 2 with is speaks to “GMRS transmitters”:
“...All frequency determining circuitry (including crystals) and programming controls in each GMRS transmitter must be internal to the transmitter and must not be accessible from the exterior of the transmitter operating panel or from the exterior of the transmitter enclosure...”
 
Michael
WRHS965
KE8PLM
 
Edited to resolve text errors.
 
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For GMRS use, be sure to get one that handles the UHF band - some SWR meters only handle HF.

Try looking up MFJ or Diamond Antenna -  they make several models of analog SWR/Power meters.

Get your self a Daiwa VHF/UHF cross needle SWR/Power meter.
https://static.dxengineering.com/global/images/prod/xlarge/dwa-cn-501vn_wu_xl.jpg?rep=False
 
dxengineering.com

When the radios were physically limited and you had to take them apart and physically remove a blocking diode it was clear that the manufacturer had actually manufactured the radio in compliance.  Compliant firmware is a major shortcut and shortcoming.

According the US importer (BuyTwoWayRadios), they have confirmed that this radio will enforce FCC compliance by way of the firmware. This is a good liability reducing move on their part. This should mean that regardless of the means used by the owner to configure the radio (VFO, front panel, factory software or Chirp) the radio should function per the FCC technical requirements.
 
https://www.buytwowayradios.com/blog/2020/11/wouxun-kg-1000g-mobile-gmrs-radio.html
 
Prospective owners should also know immediately that the radio IS NOT (I say IS NOT) capable of transmitting and receiving on all GMRS frequencies like its hand held sibling the Wouxun KG-805G. Whereas the handheld can legally transmit on all 30 allotted GMRS frequencies this mobile radio can transmit only on only 23 of them. In this regard, this puts it in the same camp as the Midland GMRS mobile radios. This seems logical due to the fact that minimum power of this radio exceeds the allowed power for the GMRS/FRS interstitial channels 8-14 (those in the 467 MHz range). This is a non-issue for those that already understand the FCC rules but for the neophyte this may be met with anger and surprise should this be their first GMRS mobile rodeo (pun intended). The use of the term “30 Channel” in the ads is sadly misleading in this context. In some radio circles a channel refers to a specific frequency and the number of channels refers to the number of frequencies you can operate on. In other circles a channel merely refers to a memory location (preset) for storing a Rx and Tx frequency, squelch codes and other associated values which the user can conveniently recall.
 
So, in summary, this radio can only Tx on 23 GMRS frequencies but can receive on 30 GMRS frequencies according to current public information.
 
Edit 1: I re-reviewed the language in the FCC Regulations and found 95.1763 (d) “467 MHz interstitial channels. Only hand-held portable units may transmit on these 7 channels.” So here there is no gray area. Mobile, base and repeaters are not permitted to transmit on the 467 interstitial channels.
 
Michael
WRHS965
KE8PLM
 
 
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