Leaderboard

Assuming that you are not a Government Entity or a person and/or an entity involved in basic or advance life support services, you will need to meet the eligibility requirements of Part 90.35 of the FCC Rules and Regulations. The FCC filing fees for a Radio Station Authorization (License) is $205 and that application/filing must be filed on-line. Prior to filing, you will need to file a request to register for a FCC Registration Number (FRN), if you do not already have one. I assume that you already have a FRN because in order to be on this forum you need a GMRS license and that number will be on your license. If you are filing for a mobile itinerant frequency(ies) or an approved low-power allocated frequency you will not need to have your application/filing coordinated/approved by an appropriate authorized Frequency Coordinator. If you are filing for non-itinerant mobile and/or Base or Repeater Class Station Radio Station Authorization, you will need to have your filing/application coordinated by the appropriate Frequency Coordinator and approved. The Frequency Coordinator fees are separate and inaddition to any FCC filing fees. Some coordinators have posted their fees on their websites In most cases, if you are applying for a specific frequency or a pair of frequencies, you will need to submit a radio communication propagation study/coverage plot map with the required contour plot study. You will need to provide the technical data regarding your transmitter site location, tower height, antenna placement height at the tip, output power, antenna height above the average terrain, and maybe a radiation exposure study. Also, you may be requested to provided a frequency interference study depending on the requirements of transmitter site. It my be best to let the Frequency Coordinator select an usable Frequency for your requested coverage area. It is my understanding that the FCC will not longer approve any filings/applications for Statewide coverage. They (FCC) expects filers/applicants to apply for and use itinerant frequencies for statewide coverage. Filings/applications for a specific geographical area will only be granted with a specific radius from a center point and that point must be exactly identified. Don't forget to specify all the emissions types you intend to transmit with in your filing/application. You will be regulated to the listed allocated narrowband frequencies with their respective restrictions/conditions in the Part 90.35 radio service pool. Get your Visa/Mastercard ready.

Awesome, thank you for the kind words! Everyone is welcome to use the PowerPoint show and the video. If it's helpful, please feel free to share them.

Marc, Excellent presentation and PowerPoint. I was starting to create a GMRS PowerPoint when I found yours. What a great help. Thanks, Terry

Where more power really helps is in signal to noise ratio.

Exactly! I’m sorry, I didn’t get your call sign, can you repeat again? And you’re a 59 into Butte!

This is also true. And the same goes for mobile antennas too. A 9 dBd antenna will work better in a more wide open and flat area where a 4-6 dBd antenna will work better in hilly/mountainous areas. The higher the gain is, the flatter the radiation pattern is. The simplest way to explain the effects of gain is to use a beach ball. Lower dBd will have a more rounded radian pattern. The higher the gain is, the flatter the pattern will be. Yes you can get out farther with 9 dBd of gain but the pattern will be narrow compared to 4 - 6 dBd. The advantage of lower gain is the pattern is more spread out and has a chance to get around some obstacles. In my case, I was getting into that repeater 50-55 miles away with 20 watts. But other people had a hard time hearing me due to noise on my signal. Switching over to my 50 watt radio made the difference and everyone could hear me clearly. I have another repeater the same distance away in the opposite direction that I can hardly hear let alone get into. The difference is the height of the two repeater antennas and the terrain in-between us.

Does that Laird have phased collinear elements to cause it to propagate more powerfully below horizontal? HF operators frequently have an issue when they mount an antenna too near to the ground (the recommended height is greater than or equal to one half wavelength) and as a result their propagation pattern is deformed to mostly skyward. That’s especially common with longer wavelengths; it’s difficult to mount a 160 meter wire antenna 266 feet above the ground.

At the end of the day, more power does help. Thank-you

Power is probably the most over emphasized part of VHF or UHF radio comms. There isn't much practical difference between say 20 and 50 watts assuming that the coax feeds and antennas were the same. VHF and UHF being mainly line of sight bands, terrain becomes your limiting factor long before power does. 50 or 500 watts will not defeat the mound of terrain between you and the receiving station. Only getting your antenna physically higher will. But once you've accomplished getting your antenna up into the clear, again, it doesn't matter if you're running 20 or 50 watts. It'll get out and sound essentially the same. Heck, even 5 watts if you're getting it through your coax feed enough to have a reasonable amount of it left to squirt out of the antenna. Consider this. Voyager, that is now hurdling through interstellar space, is equipped with a 33 watt radio. And is currently still in touch with Earth. When you conceptualize that an antenna in the clear, is an antenna in the clear, you'll understand that it doesn't even matter if you're running a 15 watt GMRS radio or a 50 watt one. I see a lot of people wasting a lot of money and energy buying 50 watt GMRS radios and dealing with the hardwire install needed for the amp draw needed to run it at 50 watts. It's largely a waste.. Concentrate on your antenna, geography, and coax. The actual radio part of radios (generally speaking) are interchangable appliances. The science of success in radio is entirely done at the antenna level..

Switching to lower power and not getting in to a station that receives you on high power is most likely because their squelch was turned up too high. The signal is most likely still there, just below the squelch level setting. As Steve said, in the fringes, more power brings you up out of the noise. 1 thru 10 notches in software is harder to change than the old analog knobs we had on our CB's. Some radios have a preprogrammed button to turn off squelch (I think many of them are labeled "monitor"). Other radios will require you to assign the function to a button. You should always use this function when doing tests as described in my first sentence.

I gave-away my DB-25G a long time ago, but when you do a factory-reset, does that not return it to the factory original image?

First of all, I can't really give you a straight answer, because the General Mobile Radio Service has through a lot of changes over the 30 plus years. You really shouldn't assume that GMRS Ch-19 will sound like the CB Radio Ch-19, because it doesn't.

No doubt. Especially when the receiver has a good processor in it, it won't take much.

HF is definitely odd. Sometimes I will increase my power from 100w to 750w-800w before signal reports improve. Then again, depending on who I am talking to, everyone is a 5 9 anyway. LOL

Yes the general rule of thumb is to quadruple your power in order to make a noticeable difference. But just doubling the power output can sometimes make a difference. For the OP, he would be quadrupling his power output going from a 5 watt radio to a 20 watt radio the using a base antenna with both radios. He will definitely notice a difference going from 5 watts to 50 watts. I know HF is a different animal compared to UHF. With HF you really don't notice a difference until you quadruple your power say going from 100 watts to 400 watts. Most won't notice a difference on SSB going from 100 watts to 200 watts.

Sure... that makes sense. The propagation was already working in your favor. Increasing your transmit power should help. Just keep in mind that you need to increase your power 4x (6 dB gain) to get a noticeable improvement at the receiver.

I'll somewhat agree with Marc, antenna is the most import piece of in arsenal to get out. But not every antenna is treated equal. Power does help. After testing/playing with four different antennas ranging from $25 bucks to nearly $400, i found the $400 antenna is the poor looser over distance (in my situation)... My little home brew copper j-pole seems to be the big winner.. My old Hustler was a winner as well.. After studying some (very little) antenna theory i'm finding that antenna take off angle has a lot do do with how far and how well it can transmit/receive. The current Laird i use for base has a sharp low angle take off angle and I learned is meant for mountain top applications not 40' above your home. Most of the signal is basically hitting dirt, not elevated air. The J-Pole has a wider pattern where it works better at lower elevations. I think Power helps more with a J-Pole over a higher gain narrower patter antenna. I'm by far not expert in Antenna theory but i am trying to learn more with it..

Things to consider if going from an ht like a KG935G to a 50W base. A dual conversion receiver such as a KG1000G will often give less noise and interference from a variety of sources. A KG1000G offers simultaneous monitoring of two channels. That way, you can monitor a repeater and a simplex channel, two repeaters, or two simplex channels, at once. Weird as it is, propagation and parts of the antenna received and transmitted from on a given antenna or antennas, can change drastically with a frequency change as small as 30 or 45 KHz. I know I am comparing apples and oranges, but a couple of friends and myself used to rag chew on 2m (VHF) simplex. We were using different gain type antennas and brands. We might hear each other "okay" on 146.550 MHz. We could switch 146.580 MHz and hear each other way better, with stronger signals all the way around. There was no interference from adjacent channels, intermod, etc; just noticeably stronger signals. You could monitor say 462.550 on one side of your base. If, for some reason, your ht or mobile went into a null, it is possible that they could switch to a secondary monitored channel, say 462.725, and get in good enough for you to hear them. Also, with a good power supply like an Astron or similar, leaving your base turned on and monitoring at all times has advantages. Another thing, if worn "on-body", there will be significant attenuation of transmitted and received signals with an ht. A 50W base has a better chance of being heard on the belt-worn radio. Of course, once the wearer takes the ht off of their belt, its signal improves both xmit and receive, when in-hand as opposed to against your body. For this reason, I do not recommend using a speaker/mic for an ht on the belt unless operation will be at very close range.

SMR's were the original business band analog trunking systems in the 1980's. You probably need to do a deep dive if you plan to try to build out something using 800/900 MHz freq's. Most of those original SMR's were bought out by Nextel (which implemented a digital cellular-like technology known as iDEN, and operated under an FCC waiver as an eSMR - enhanced SMR). Almost all of those old SMR freq's now belong to Tmobile. There's some limited Licensing opportunities in 800 MHz for smaller businesses, but it's a pretty steep learning curve to figure out what's available in your area, and what it might cost you to get up and running.

Increasing the transmit power of a UHF radio signal does not directly affect its ability to refract, diffract or scatter beyond the horizon. Though, it increases the PPM of photons that are refracted, diffracted or scattered, increasing the ability for receivers to pull the signal. Again, transmit power does not fundamentally change the propagation mechanics of UHF waves, but it can improve the reception of signals that are already being refracted, scattered, or diffracted.

i have both versions of the J-Pole, both home brew and favor the Copper J-Pole over the Twin Wire J-Pole.. I use the copper j-pole for a portable repeater while camping. Getting the SWR's to perfection on the Copper J-Pole is a major PITA so i came up with a method for adjustability (see pics). Not shown in the attached picture, i had to grind down 1/2 inch on one side on each of the adjusters. The adjusters are made from a modified crimp on copper splice (Home Depot) and removing the internal rubber gaskets, cutting the splice in half then tapping for the set screws. It works great, i'm able to get 1:2 - 1:3 on my repeater channels (18)... The Copper J-Pole has talked roughly 90 miles, I've gotten about 60 with the Twin Lead version.. Both better than my home Base Laird FG-4607 and i can't figure out why on that one..

i run a copper J-Pole (Home Brew) on my portable Maxon repeater (40W), in my RV mostly up in the Sierras near and around Crawley Lake and Mammoth. The last weekend of last Sept i talked with Terry on his base station in Tonapah while relaxing at my RV , about a 90 mile hop. When i switched to medium power he lost my contact. On high power he hears me loud and clear. So im gong to debunk those that say power does not mater. Yes it does!! And BTW,, the copper J-Pole is a nice antenna, they perform well.. KB9VBR gave me some tips on getting one to work aside from what the calculations tell you..

And they were purchased from a huge warehouse operation that doesn't specialize in the sales of quality two-way radio products.

This is true. We see people go cheap with Amazon chinesium coax or the wrong type of coax. Or they buy the cheapest (and lowest quality) antenna they can find on Amazon. No amount of power out of the radio will overcome lossy cable and/or a craptastic antenna. I had to say something to a guy that lives 300 yard down the street one time about this subject. He accidentally swapped his coax cable on his HF and VHF antennas. He had the RG58 hooked up to his VHF radio and wondered why it wasn't working like ti use to. So his answer was to hook up a 160 watt amplifier. All the amplifier did was cause me grief since we are so close to each other. I told hm that ne needed to swap the coax cables back around. But I have no idea if he did it or not. At least he isn't running the amplifier anymore.

Unfortunately a lot of people spend their money on RF output power at the radio and then waste it by using lossy coax and cheap antennas.

It's a bug or perhaps a feature of the firmware. This radio is a clone of the Radioddity GM-30. Radioddity did a firmware update back in 2021 or 2022 that opened up DIY repeater channels on Channels 31-55 as I recall. The remaining channels are still Receive only. See NOTE below* I believe the Baofeng UV-15 Pro is the same, but I do not have one to test. I purchased the Baofeng UV-13Pro from AliExpress some time ago ($20) and it is the Ham Radio version of the 15, already open so as to allow transmission on GMRS and MURS on ALL channels. I also recently picked up its baby brother: the UV-12, which is the Ham Radio version of their FRS radio, again open on all channels: * Here is a link to the Radioddity firmware update page. Attempting to update the Baofeng GM-15 with Radioddity firmware may BRICK your radio; so do it at your own risk! https://www.radioddity.com/blogs/all/how-to-update-radioddity-gm-30-firmware

I can give one example where 50 watts helped compared to 20 watts. Otherwise I have to agree with everyone that antenna height and quality coax makes more of a difference. My shack setup as far as the antenna goes is; Comet CA712-EFC with the base at 22 feet above the ground, 30 foot of LMR400 from antenna to the wall pass through and a 15 foot LMR400 jumper inside. There is a repeater that is 50-55 miles away. I can get into it with my Wouxun KG-XS20G but there is quite a bit of noise in my transmission. I get in to that repeater and am heard clearly with the extra 30 watts from my WOuxun KG-1000G. Going from 20 watts to 50 watts did not change how far I can talk but it did make it so that I am heard better at the longer distances. Now getting my antenna up another 10-20 feet and away from all the trees in my yard would make a big difference over actual output power of my radios. To answer the original question. YES you will see an improvement when going from a 5 watt radio to a 20 or 50 watt radio. You are quadrupling the power going from 5 watts to 20 watts. This is when everything else is equal such as connecting both radios to the same antenna and coax.

Changing the subject a bit, what software are you using to program the GM-15 Pro? A friend recently got a pair and they don't seem to be supported by Chirp, but I know sometimes a related radio's profile will work. Are you using Chirp or the proprietary software?

Although I don’t have one, I would offer this advice. Waterproof the connection and have extra cable. The antenna appears to have a weirdly short UHF connector, rather than an N connector, and it’s not recessed as it would be in many professional designs. Thus, all water that runs down the body of the antenna will eventually end up at the UHF connector. Unless sealed it will eventually permeate the end of cable. Once moisture gets into the dielectric between the center conductor and the shield, you’ll need to replace the last several feet of coax and re-terminate it and then seal it. Other than that I know nothing about the antenna and the specs reveal nothing. It’s a piece of wire in a fiberglass radome (tube). The only things that matter are does it work for your particular situation and how long will it last? The answer to the first appears to be yes. You seem satisfied. As long as the fiberglass holds up against UV and the metal doesn’t corrode and the cable doesn’t fail due to moisture permeation, you might get years of satisfaction.

I personally wouldn't know, never been to Shreveport LA. Then again, I've only traveled the I-95 corridor between Florida and Massachusetts, not on the same trip. I sure hope someone is able to help you out there, because I wish I was able to Now, if you every venture in Southeastern Pennsylvania and Southern New Jersey I could help you out. May 2025 bring you and kin folk joy and good health!

Other aspects to consider about antenna gain A higher gain antenna does not create more power than the radio produces on its own. Antenna gain increases or decreases signal directionality. Looking at antenna charts demonstrates the signal pattern of an antenna. Notice, the higher the gain the more directional its signal pattern becomes; think Yagi antennae. Consider your location of use, then chose the appropriate antenna. Using an example of an adjustable lens flashlight (torch) such as the Maglite: Remove the adjustable end exposing the bulb only, notice the produced light may fill a dark room; think low gain antenna. This why a lower gain antenna is much better in an urban area, in areas with much more obstructions, in forests, and the like. That is why many folks in locations with buildings, many obstructions, forest, and the like, when switching to low gain antennae have better TX and Rx signal reports as well. Now connect the adjustable section and its lens to the flashlight, adjust it. Notice it is now concentrating the light in a much more directional beam. Now the light does not fill a room with light; it performs better pointing into the room; think high gain antenna. The higher gain antenna performs better in less obstructed areas, such as open roads without obstructions, mostly flat landscape and the like. Thus, in considerably more open unobstructed locations switching to a higher gain antenna will increase its reach. Keep in mind, the radio is outputting the same power to the high gain antenna as it does to a lower gain antenna. The difference is the high gain antenna is creating a more directional signal. Yes, the above is an odd example, however I hope it makes sense.

How about a way to cancel a repeater access request? I have a pending request that I no longer need.

The only thing I would add to what Steve mentioned is that 50 watts will help overcome antenna cable losses while transmitting. If you are barely receiving a signal from someone using 20w and you're feeding a coax that reduces your 4w-5w handheld signal down to 1.5w or less into the antenna... that other station isn't going to hear you. So, more power and a good antenna would be a good choice.