Manufacturers power and range claims exposed!

FRS / GMRS Radios
1

I’m a GMRS licensee and amateur radio operator. I’ve been involved with FRS and GMRS for several years. A lot of folks get confused… hopefully I can help.

The best way to determine output power is to get the FCC ID number on the back of the radio. From there, you can go to the FCC website and get the actual power output off the type-acceptance grant.

Many manufacturers, Midland is the biggest perpetrator… like to give incorrect power output claims. Midland’s “5-watt” radio is actually a 1.6 watt radio. They advertise “full legal power” This is wrong. GMRS regulations indicate full legal power at 50 watts ERP.

The Cobra LI6000 (FCC ID: BBOLI6000) is listed here with a 3 watt power output… in reality the power output is a dismal 0.372 watts… on High… on low it is a mere .006 watts! FAR below even the .5 watts allowed on FRS.

They advertise those as 18 mile radios… their best 2006 model!

At least their 2007 lineup actually has a greater power output… over a watt, so thwy may have decided to improve things a bit.

Most manufacturers rate their radios at Input power to the transmitter stages… NOT the power actually emitted by the radio. Since FRS/GMRS combo radios are not authorized an exernal antenns, power should be measured at Effective Radiated Power (ERP), which is the power actually transmitted over the air.

Here is where you can look up the FCC Data:
https://gullfoss2.fcc.gov/oetcf/eas/reports/GenericSearch.cfm

You just need to input information in the first boxes… Grantee code and product code. You’ll be brought to a page with tons of information.

A common trend is to actually lower the output power while increasing the range claims of radios.

All they want to do is sell radios. They want to slap them together cheaply and sell them quickly.

You want quality… get a GMRS license then buy commercial-grade equipment.

NO radio will get you over 2 miles under average conditions. 25 miles only over the ocean or in space.

I have a website that may provide useful.

http://www.geocities.com/gmrspage/

BTW: Oners of this site… I appreciate your honesty in addressing questions… especially the licensing questions. Many businesses omit the licensing requirements or lie and say there are none. You answered the license questions honestly… I appreciate that. The GMRS community appreciates that…

2

the fcc link does not work, actually it seems like it is really tough to find the truth out.

3

I noticed the link doesn’t work. I’ll get another one here… they changed it.

Try this one:

https://gullfoss2.fcc.gov/oetcf/eas/reports/GenericSearch.cfm

If I can edit my original message, I’ll change it there. too

4

do you have the fcc id for the Midland GXT-850-VP4 and Motorola T9550XLR?

5

jwilkers,

Thank you very much for the informative post. The FCC web site is a great way for consumers to get an idea of the true capabilities of their radios, and is a great way to compare models for those willing to do the research.

We want our customers to be as informed as possible and think it is sad the way these manufacturers have gotten into this game with their crazy range claims. We speak to customers every day who are confused by this, or are disappointed in a product because it isn’t giving them the 18 miles it advertises. I think educating consumers is the best answer for this, and hope this forum helps accomplish that.

For those looking to research products on the FCC site, I am going to provide a list below of the 3 digit “Grantee codes” for the manufacturers whose products we carry. With the grantee code, you can get a list of all products approved by the FCC for that manufacturer. The “product code” is usually the same or similar to the model number.

K7G - Motorola Talkabout radios (manufactured by Giant International)
AX4, ABZ - Motorola business radios
MMA - Midland
BBO - Cobra
AMW - Uniden
R74 - BlackBox radios (manufactured by Shenzhen HYT)

If anyone looks up specific models, please post the wattage to this thread. Once we get a few products listed here I will sticky this post so that it always shows up on top in the list.

Danny

6

MMAGXT850 on the midland… No clue on the motorola.

The midland has a power output of 1.63 watts.

FAR below their outrageous claims.

7

You’ve been very honest and informative too. I see so many people all the time getting confused. Manufacturers all want to sell radios… they don’t care about truth (or the whole truth).

Each year brings new models with greater and greater claims of enhanced range, whaile actually lowering power output in some cases. My communications to these folks go unanswered.

Even my amateur equipment which has REAL power outputs of 5 watts and over can’t attain these ranges… unless I go through a repeater or connect to an external antenna.

Until the public is educated and understands these games, the manufactueres will continue to get away with it.

8

The thing is, the radios that they are producing definitely fill a need and are quite popular. The better products do really well for groups needing short range communications between around 1 (and sometimes up to 2) miles. They are perfect for many situations and they save people hundreds of dollars over commercial equipment.

I think these range claims are hurting them more than helping. If they were only more honest about the actual range of the radios, I think they would get even more customers in the long run. When people look at product reviews on sites like Amazon, where there are many negative reviews that all seem to be range related, they get turned off on these products in general. Also, it has to be costly to handle calls dealing with customer complaints and returns from unhappy customers.

Maybe Motorola is on the right track. On their new products they advertise the maximum range on the front of the packaging, but on the back is a diagram that shows the maximum range in three types of settings: mountain to valley, open water, and urban.

Danny

9

This is true. Their packages are more honest. The “Mountain to valley” was humorous, since how many people would do that. Still, this is true. Also, over water, you can expect greater range. In town the 2 mile range is realistic. I’ve still yet to do the person-to-person outside tests; but it does seem possible to get 2 miles.

10

Power vs Range
I have been playing with a pair of COBRA model PR3850-2 WX EVP units rated at 12 mile range and have found this much to date.

The power consumption from the batteries with the loaded voltage at 5.68 volts is 275 MA in the low power mode and 733 MA in the high power mode. Using this information as a starting point the following assumptions are made concerning the output power.

Using Ohms law, P=E X I, 5.68 X .275 = 1.562 watts. This is the total power required in order for all of the electronics to operate in the “LOW POWER” transmit mode. Assuming that this unit would be outputting 1/2 watt (500 mw) as specified for FRS maximum power one could approximate the relative RF power by subtracting the 1/2 watt assumed output power from the additional power consumed.

1.562 - .5 = 1.062 watts consumed by all of the electronics other then the actual RF power needed for the output stage.

Remembering that in the high power setting the current was 733 ma. 5.68 X .733 = 4.16344 watts minus the 1.062 = 3.10144 watts of approximate input power. Most class “C” R.F. output stages operate with an efficiency of 80% typically so by subtracting ~ 20% we have a remaining final output power of 2.48 watts.

To confirm this I modified the stock antenna with a BNC connecter and connected it to a watt meter with a 50 Ohm termination and on the 10 watt range I could see a reading of ~ 2.5 watts. This was confirmed on two other meters as well.

I hope to order from you this week a set of MIDLAND GXT710VP3 rated at 26 miles and do the same. Hopefully within a few weeks I should see how closely this emulation works.

One other assumption I am making on the mileage ratings within the same manufactures clams is that if the power rating given is the same 5 watts (regardless of the actual power) over another model the receiver sensitivity and or signal to noise ratio must be better, another specification never mentioned. --mike shearer–

11

This maybe a true statement! As the technology improves the receivers capture and signal to noise ratio also improves. It is far less expensive and more cost effective from a manufactures point to build a better receiver into the newer units employing higher gain and/or lower noise figures then to implement much more expensive power output devises that will suck up more power while lower the battery operating life attribute.

Why has no one on this board ask anything about the most important range factor? That is the receivers front end capability, sensitivity in µv., capture, image rejection and the like. Ignoring these issues will undoubtedly affect the mile range drastically more then the output power factor at 462 Mhz. I/E do not allow the manufactures to tell you what to look for in specifications.

Every manufacture must have the same most important feature no mater what the product is that they make, that selling feature is PROFIT!

In order to remain competing with the products that they manufacture, they must also be time proven with reliability otherwise they will soon file for bankruptcy protection.

As a former manufacture myself I understand the fine line they must walk everyday. --mike shearer–

12

Remember, these radios are rated at ERP… Effective Radiated power. This includes the antenna. The power ratings you come up with are TPO, transmitter power output. (Still useful and helpful information, as it leads to proving manufacturers are using the more or less useless figure of input power.) I get my power output data from the FCC database… I think the link is posted in this thread… that could prove your formulas by comparing your TPO readings, minus antenna loss.

13

Here is the info for the Motorola T9500XLR and T8500R. I tried looking for some of the other models but, they don’t show up. Must be under a different manufacturer. I am surprised at the low wattage of the T9500. I would have expected it to be higher.

FCC IDENTIFIER: K7GT9500
95A 462.55 - 462.725 1.03 Watts
95B 467.5625 - 467.7125 0.11 Watts

FCC IDENTIFIER: K7GT8500
95A 462.55 - 462.725 0.676 Watts
95B 467.5625 - 467.7125 0.26 Watts

Harry

14

I just bought 3 sets (6 total) of T9500 for use on hunting trips in Africa. (Not opened or tested yet.)These radios will be used for communications between hunters in fairly flat savanna and bushveld areas, more than 50 miles from the nearest town. What range can be expected and is there any way of extending the range as this will not interfere with any other radio signals (there are no others in the visinity).
Louis

15

Bear in mind you may be interfering with official users of these frequencies in Africa. Those frequencies are only approved for use in the USA (and Canada if the radios are IC approved). Other nations use these frequencies for public safety, military, and other non-personal uses.

I know in South Africa, FRS/GMRS radios are illegal even to own. If caught in some countries, you are guilty until proven innocent with much more harsh legal systems than here in the USA.

Just because you don’t hear anyone, doesn’t mean the frequencies aren’t in use.

16

Compared to some radios out there, these aren’t too bad. (the 9500s) It seems one of the current trands is to reduce power output. It’s rare indeed to see a radio made with a power output exceeding 1 watt. The Midland GXT850 is about 1.6 watts. This is actually a reduction. The old GXT 325s had a power output over 2 watts. When I did a review on those years back I had a communications range over 3 miles. Back then they were advertised as “18 mile” radios. The new 850s have a lower power output but have a greater advertised range.

17

Are you 100% sure that no improvements and or changes were made to the newer receiver circuity?

Are you assuming that both receivers are IDENTICAL?

We can not assume that range between any two units is based only on the transmitters effective power output unless receive circuits ARE identical.

How much range could one expect with a 50 watt transmitter and a crystal set type receive circuit?

The most important point about UHF radio range is that ANTENNA HEIGHT is more important than the output power of the device.

–mike shearer–

18

I have no information either way. Why would an older model perform better? If there were “improvements”, then you’d think the newer model would perform better. I reviewed the older models as having at least twice the effective range of the newer models.

19

Very good point you make :eek:

The point that I was trying to convey to the other members is that many more factors then transmitter power will have a greater impact on any range tests.

If you have the time you may want to employ your most realistic (no pun intended) testing one step farther. Pick the best transmitter with the most output power that you have and use it as the reference base unit, then take both the newer and the older units remote as far as you can until one receiver can no longer capture the base transmitter and this test should determine the best receive range.

It is extremely important to remember all squelch functions must be DEFEATED while conducting any range tests, otherwise any range tests will not be valid!

The older and the newer units were more then likely not tested the same way at the same locations, who is to say what the manufactures testing configurations were or currently is. Field testing on transmitters and some other signal generated standard maybe how they do it. I/E theoretical lab testing only

The testing that you are doing and reporting on are much more “Real World” then any biased manufacturing calculated standard(s). Thank you for all the information that you are suppling the other members with;)

20

I no longer have any of the older units.

A lot of my stressing power output has to deal with the fact manufacturers in some cases advertise their power output as one figure, and the “real” power output is another figure entirely. (They conveniently use a different measurement to make their radios appear more powerful). Since antennas to be rules compliant for FRS cannot have gain; antenna design shouldn’t be too much of a factor, although “unity gain” and “negative gain” can certainly play a factor :slight_smile:

I do all my tests a “real world” as possible. I use each radio with its mate. I don’t mix brands for two reasons: One, it is more likely for a family to use the same radios, and two, I want a “pure” test result.

I keep squelch enabled. one, for realism… most folks keep their squelch enabled, and two, because the ranges I report are effective (useable)ranges. These ranges are where reliable contacts are possible.

My reviews are designed for the average consumer. I keep them simple and as easy to understand as possible, where maintaining accuracy. I’m not concerned about technical aspects of the equipment, since that is over most people’s heads. People don’t want to know receiver sensitivity, they just want to know how far they can talk, and how easy the radio is to operate. As such, receiver sensitivity is “built-into” the review, as it is a factor in determining range. Further comparisons or more detailed evaluations would deviate from my whole point. I use no test equipment, other than Google Earth, to draw a point-to-point line to determine distance between test points.

Simplicity is the name of the game. The average consumer just wants to know the bottom line. Your suggestions certainly do have merit, and dig more into the whole picture; but they are above and beyond the scope of what I try to accomplish. I also try to break the advertising hype of manufacturers, with hopes that getting the word out will motivate a bit more accurate advertising in the future. I am not saying the manufacturers are lying, I’m saying that statistics are being calculated to bring products into a more positive light than my tests may prove.