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I finally made the purchase of the HD 46’ push-up fiberglass mast I referenced in my earlier post. This weekend I rigged things up in a temporary way to conduct tests with local (and not so local) repeaters, as well as do some local simplex work. The image below shows my antenna at full elevation (56’ AGL to tip of Antenna). Mast was installed in a temporary way just for testing. Eventually it will get moved next to the house. Amazing how plumb the mast was being guyed only at 7’3” (not good long term, but good enough for testing). The antenna is a Comet 712EFC Collinear 9dBi. https://www.dxengineering.com/parts/cma-ca-712ef Cable is TMW LMR400 Mast is from DX Engineering. https://www.dxengineering.com/parts/dxe-tfk46-hd All of my testing consisted of using two handheld 5w radios. One feeding the Comet antenna, one in the car using an MXTA-26 antenna. First, the high-point of the testing. I was able to communicate from my home southeast of Cincinnati to the Dayton 700 repeater located 50 miles north(straight line distance) using approx 3 watts of input power into the antenna. Signal report from a Dayton area resident was “very good” and “into the repeater solid”, perfectly suitable for a QSO. That alone made my weekend. On the local front I was able to get into three local repeaters located 20, 21 and 26 miles way. Got in with full quieting to the one 20 miles away (“just as though I was next door”), and with just a hint of noise on the ones 21 and 26 miles away. Getting the antenna up high obviously makes a huge difference. On the simplex front I found I could achieve pretty reliable coverage out 4 to 5 miles where things transitioned to hit and mis out to about 7-8 miles when all seemed to die completely. I expect the reliable range will decrease as foliage comes back. Not bad though for a couple of lower power HT and with good external antennas. It will be nice to experience the positive change to simplex coverage after I up the power of the base and mobile to legal limits. Michael WRHS965 KE8PLM

What does “duty cycle” mean? I bring up duty cycle every time I hear somebody talking about making a repeater out of cheap Chinese mobiles and worse any type of handhelds. Duty cycle is the maximum time an amplifier may transmit within a five minute interval, expressed as a percentage, to avoid overheating. Suppose a mobile amplifier is rated at 30% duty cycle. This means that it may transmit for no longer than 1.5 minutes and must remain off for not less than 3.5 minutes. Some people forget that a repeater is transmitting for 2 or more people, duty cycle will be reached quickly if you get into conversation. More people in the conversation just amplifies the issue. Once a radio reaches it's thermal design limits it will no longer be able to adequately cool the output transistors. Even if a radio is not hot to the touch the transistors are, in part because of the inefficient transfer of heat to the units housing or internal heat sink. The longer you exceed the duty cycle the more heat builds on the transistors, surrounding electronics and heat sink effecting it's ability to remain on frequency without spurious emissions. Exceed duty cycle long enough and you will need a new transmitter or radio. I have tested a few Baofang and TYT radios on my service monitor without great results. All of the radios started deviating outside of the allotted channel bandwidth after simulated conversation at 50% duty cycle, the longer I allowed this the worse if got. Testing was done using an Aeroflex 2975 IFR recently back from the calibration lab. GMRS is a tiny sliver of spectrum surrounded by the commercial land mobile part 90 service. It is important that any repeaters that are built or re-purposed are held to the highest standards and operated as to not cause any interference inside or outside of our allocated spectrum. I wont get into the part 90/95 debate but i do stand firm that non certified import equipment has no place on GMRS.

Ok; so ran into another interesting development on this today: I ordered a Retevis RT29 last week; seemed like a durable radio, although I expect the internals to be less than great. The IP67 rating, 2-year warranty, and 3200mah battery appealed to me - for $50, again, a cheap beater radio to throw around the woods that supposedly lasts almost a week on a single charge per some of the reviews (curious to verify that) and is supposedly submersible (also curious to verify that) This model is listed on FCC ID 2ASNRT76, which uses the RT76 as the primary radio, declaring the RT1, RT26, and RT29 as identical models. Retevis didn't answer my email I sent them before I ordered to see what the FCC ID's were on this radio (they stated they forwarded it onto engineering but never heard back). This showed up in the mail today; this radio is indeed badged compliant with the 2ASNRT76 FCC ID... so a legal Part 95E radio??? First impressions on the RT29: Again I don't expect great things from this radio performance wise and I literally got this in my hands with the sole intent of finding out what the manufacturer would send me, so take it with a pound of salt; the build quality feels excellent from a mechanical standpoint - very solid, not a creak to be heard, and feels similar to my TK380s and TK390s in terms of dead weight and general physical solidness. Feels a lot more sturdy than the KG805G which I'll say comes across as lightweight, although the bonus on that one is more so the memory channels and the receiver. I'm pretty sure you could knock someone out with it and still carry on a QSO. Perhaps a good radio for family use while you keep the high end gear for yourself... Firmware wise the RT29 is not locked to GMRS, and will do 400-480Mhz and will also do wideband and high power on the 467Mhz interstitial channels (I should note that dual part 90/95A surplus can do this too so that's probably not an actual deal-breaker and its up to the programmer to get it right). The radio I received is only listed for Part 95E, you could use it on the ham radio service but of course that's also not allowed per the FCC rules if you use it on GMRS as well.... so really just a legal GMRS or ham radio (not both), and even then you probably can only use it on medium power (5 watts) since that's what the 95E cert is limited to. First Impressions on the KG805G: now that i've had it for a few days with real-world use; it's indeed not a very selective receiver and does pick up and suffer from adjacent noise and interference fairly readily, it does do better than my UV82 (consider that a GMRS-V1 analogue) overall which is its competing market, but I will say that in low noise environments the receiver is very sensitive even with the stock antenna. In a clean environment, it seems to have a slightly easier time picking out signals than my Kenwood TK380, 390 and 3180 so its not without merit for a starter radio I'd say, and not a bad deal at all for a new radio with part 95 cert. Audio is generally very clear although lacking lows, but I'm also spoiled by Kenwood on this, transmit audio sounds excellent. The UV82 provided a richer sound due to the larger speaker, but it's also not as clear and easy to understand. Programming the channels beyond channel 30 works as advertised and is a big advantage over other panel-programmable GMRS radios in the current consumer market. I wish the radio felt more solid and had some more 'oomph' to it but honestly it's probably fine for most users. Havent thrown either of these on the spectrum analyser and power meter to see what they put out; but will get to that in time. If causing interference is indicative of transmitter cleanliness and used as an unscientific benchmark, the KG805G does readily knock my computer monitors offline, causes Lucifer himself to type random incantations on my keyboard, and also puts my computer in sleep mode as does the UV82. The RT29 also does, but less easily and only at 10W high power. The Kenwood commercial radios do not do this at all even though they put out the same amount of power as the 805 and 82.... things that make you go hmmmmmmm....

Since I'm newbie, I watch all the post... It looks like your Icom was replace with https://www.buytwowayradios.com/icom-ic-f4001-03-rc.html . Saying New version with Lithium-Ion Battery and Charger!. IMHO.. I got a two starter radios, KG-805G which is a CCP radio. Icom is Japanese. I am an old Motorola guy but they're not the same as they were years ago with all the gotcha. Did you see the posts on review of radios? https://forums.mygmrs.com/topic/2183-brand-name-radios-proscons-thread-usednew/?hl=icom https://forums.mygmrs.com/topic/2183-brand-name-radios-proscons-thread-usednew/page-2?hl=805g&do=findComment&comment=20996 Check it out... a lot of reviews so search the forum. I use more then 16 channels. I set my radio up to standard FRS and GMRS as well as the repeaters I can connect to plus a few GMRS channel low and high power with PL codes that we use as a family. Also a few travel repeaters... That added 6 more channel slots. So I scan all channels and go to any of the ones I want to connect with... The family is scanning as well and I tell them what channel to go to.... Works great. Happy investigating... Whatever you pick will be the best for you, so let us know what you did pick... My job done, to show you why 16 channel is a limit to how we use GMRS radio for our family needs. Jack

There are a few threads on this site with MXT 400 software and programming. Try this... https://forums.mygmrs.com/topic/1837-midland-gmrs-product-updates/?p=17118 I’ve used the software that’s available in that Dropbox and it works. Need a USB to 3.5 cable to program. This is the one I purchased... https://www.rtsystemsinc.com/USB-29A-Programming-Cable_p_748.html

I wouldn't say repeater owners are trying to keep people out, rather, trying to control abuse of their systems. Repeater owners easily put out nearly $1000 just to get a system running. That doesn't include time spent maintaining the system, cost for repeater sites, cost of internet use (for linked systems,) or cost of power use. Because of this, and because there are people who simply wish to be destructive for whatever reason, repeater owners don't always disclose their access codes to the general public. This prevents unlicensed access and also reduces intentional disruption of the system. I use to publish my input codes for the public, however after an unknown user jammed the repeater forcing me to take it off the air so it didn't suffer damage, I changed my input code and did not publish it. When a licensed GMRS operator contacts me requesting the info, and I can see that user is local to the repeater, I give them the access code. Simple as that. Ask and I think most operators will grant you access.

Sorry. But that is simply incorrect on 2 grounds. 1. Many ham repeaters are effectively private and do not publish their access requirements; and 2. Repeaters are not and have never been part of what you get rights to use with a GMRS license.

What is your repeater ? While they are close a distant radio should not open up both repeaters on the PL. I would look at both repeaters and do a full check with a monitor on them.

The FCC does not explicitly limit the power of the handheld to 5w across the board. The 5w limits in the GMRS rules apply to all radios permitted to use some of the itinerant frequencies. But while the rules do not expressly limit it, the power is implicitly limited because handheld radios must comply with RF radiation exposure limits called “Specific Absorption Rate” limits. If it were somehow possible to manufacturer a higher power unit and achieve SARs compliance I suspect you would see higher power units available. Don’t hold your breath. https://www.fcc.gov/general/radio-frequency-safety-0 Michael WRHS965 KE8PLM

Effective June 29, 2021. See the attached link to access the Report & Order. https://www.fcc.gov/document/fcc-adopts-electronic-licensing-report-and-order To add or update your email and/or other information log into the FCC ULS Manager with your FCC Registration Number (FRN). See the link below. https://wireless2.fcc.gov/UlsEntry/licManager/login.jsp