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We have all asked or heard the questions before; “What kind of coverage can I expect” and “how far will those radios reach?” And we have all also heard the exact same text book answers; things like “It depends” and “that is not an easy question to answer.” You’re asking valid questions, and you’re getting valid answers. The only absolute way to know what your coverage is going to be, and how far you can reach is to test it yourself using your actual equipment in the exact area you intend to use it in. That said, technology being what is, there is a better way to get a more realistic estimate. Professionals RF engineers use software to assist them; software that will get them close. An RF Engineer in Quebec (whom is also an amateur radio operator) has a website with a free online calculator that will help the knowledgeable radio user visualize an estimate of what there coverage would be based on many of the fundamental factors that affect radio coverage. Having now contrasted its calculated results with my personal radio experiments, I am gaining confidence in its ability to “get me close.” better than any other way. For example, in some of my tests of base to HT and base to mobile coverage, the software predictions correlate with many of the spots, even along mostly level ground, where I experience complete radio dropouts, where I experience marginal reception, and where I experience highly reliable communications. Here are some of the user supplied factors that go into estimating one’s coverage: Location of Tx antenna. Transmit Frequency. Tx antenna height. Tx antenna gain, tilt, azimuth. Tx output power. Signal loss in Tx cable Rx antenna height. Signal loss in Rx cable. Real-world receiver sensitivity (which may or may not be published accurately). The calculator can be found here: https://www.ve2dbe.com The software takes into account the actual terrain around the antenna. It appears as though it may be adding factors related to ground coverage, which I assume is based on some statistical information. More detail about what goes into the calculations can be found here: https://www.ve2dbe.com/rmonlineinfoeng.html I have been wresting with determining whether there would be real-world benefit to me adding another 20-40 feet of height to my proposed GMRS antenna mast/tower. What I really wanted to know is if I would experience tangible or zero benefit from increased height when it comes to simplex coverage around my property. I feel much better informed now. I would be most curious to hear from those of you strong technical types regarding how predictions from the software align with your real-world conditions when it is configured accurately. Here is an intro to the software from a user of it: Moderators, I think this would be a useful sticky post. Happy Calculating! Michael WRHS965 KE8PLM Sent from my iPad using Tapatalk

What caused the burned paint? I don't rightly know. Bubbles appeared between the clearcoat and base paint while shortly transmitting over a two day period at 40 watts. I am a newbie to all the technical aspects antenna efficiency. I used the antenna isolator to prevent scratches in the paint as it is a new vehicle. Maybe the isolator has reduced my reception and TX when it was on the hood. After manufacturing a separate plate to set of to the side of the hood (with a ground strap) it seems to TX slightly better. I have no way to officially measure that tho. I did use the antenna to speak to a friend while he was on a HT in his hotel room and I on the mountain. Yes I would recommend the antenna for your use. 11/1/2020 Midland contacted me today to see about getting to the cause and a resolution.

I have both. The thing about the BTech I like is the screen layout. Dont know if that is possible on the QYT.

I have been using this for yrs. some things to keep in mind. gain is in dBi subtract 2.1 dB if antenna is rated in dBd. line loss , don't forget the insertion loss of your duplexer typically .5dB-1.5 dB on average. now the "required reliability" can change the map dramatically. I find that 85% works well in most applications. JE

Radio Mobile is one of the best available online coverage calculators available - especially when you consider that it's Free to use (for amateurs). My only comments would be that you need to bump up the "Required Reliability" % to something North of 95% to better reflect actual coverage. Also, realize that it's mapping Talk Out coverage for the most part - not taking into account the difference between a mobile mounted radio or a portable (other than antenna gain & height). I usually set antenna gain at Zero for a portable, with a 1 meter antenna height. I find that gives me a more accurate representation of Real World talk back conditions with a decent portable.

Well, 75' to 100' is a large difference, remember that crimping heliax is not easy without the right tools... I know this b/c I botched it before... with the tool is a lot easier. Use a string to find out the exact length, then find the next cable in size. For a 100' run I think its probably better to ask here, pretty certain others can sell you a 100' FSJ4-50B with crimped N connectors on both ends, and even a sweep of such cable. G.

Well there are really two issues here. One is cheap labor. Second is cheap design. You can still move manufacturing back to the US and still produce garbage because the design was cheap. The CCR's are the way they are because of both of the above factors. Cheap labor keeps cost down. A cheap design that takes maximum advantage of highly integrated chips which very often results in a compromise somewhere in performance with a trade off in reduced cost. Now you have a really cheap radio with so-so performance. There is a reason why the higher end radios perform better, cost more, than many CCR's is because more effort was made during the design and testing phase with less corners in performance cut. To design high performance hardware requires very careful evaluation of nearly every component used. For a $25 Baofeng just how much R and D money do you think they are going to spend on such a cheap radio? For the CCR's they use a "datasheet" reference design, tweak it a bit. Then try some "can you hear me now tests" and then it goes to marketing.

... or ANY non-GMRS certified radio for that matter. None, zero, zilch, zip, nada, rien, никто. Nobody should buy or operate any radio they are not comfortable with. Whether it is for technical or regulatory reasons. But, this board is made up of adults who, like you, are, presumably, capable of deciding for themselves what equipment they wish to own, operate, and discuss.

The cards are just fine. You've got a good eye for design. I used CheapQSLs.com for mine. They do very good work. They've got some very basic styles that are about $10 per 100, not counting shipping. By the time you do the shipping, you might as well get a couple of other features, so I got their basic style #110, but with the report on the back. Paid about $20 with the back report and shipping for 100 cards. I think I've used 3 so far. I tend to use eqsl.cc for most of my QSL reports, or the logbook on QRZ.com. At one time I put a lot more effort into them. Way back when, I got a case of sprocket-feed, micro-perforated pre-cut cards for my printer, and I printed a custom card for every QSL. It was a ton of work and not really worth the effort. About 3/4 of the case of card stock is in a closet in my old shack upstairs, untouched in about 18 years. And yes, it's QSL card. Not QSO card. A QSL acknowledges a QSO. 73, Gwen, NG3P

Nevermind, it was a mechanical issue. One of the wires in the remote cable came out of the connector and didn't make contact with the pin. Inserted it into the connector and I'm in business.

neither option is a good choice. I started out with a cheap e-bay duplexer (Around $125 if I recall) and it never worked. I was lucky to get two blocks range. Turns out the TX side wasn't being blocked by the duplexer, and instead, the RX side was loaded with desense, causing the repeater to not "See" the incoming traffic. You'r better off researching Band Pass / Band Reject (BP/BR) duplexers and purchasing one when it becomes available within your price range. I spent about $300 for mine and it drastically improved the range of the repeater. Now my only obstacle is height! You can run two antennas however you will need enough vertical separation, about 30-40 feet worth, to avoid desense and damage to the RX radio.

For anyone looking in the future, I found this.

It takes a KPG-46. Here is the one I bought, and the seller I bought it from: https://www.ebay.com/itm/USB-Kenwood-Programming-Cable-TK-780-TK-880-KPG-46p/152618254912?hash=item2388c1c240:g:JnkAAOSwytJaBd~n I've programmed TK-880s, TK-780 and TK-981s with it. Works perfectly. BlueMax49ers stands behind his cables, too. If you ever decide to get a TK-981 (which I recommend because there are some on ebay now for about the same price as TK-880s) and avail yourself of the 900 MHz repeaters that are in your area, that software and cable will program them too. There is also a really good network of GMRS repeaters in your area, which I'm sure you are already aware.

link to software https://hamfiles.co.uk/index.php?page=downloads&type=entry&id=radio-programming%2Fkenwood-programming%2Fkenwood-kpg-49d-rss_2 the TK-880 s are great radios welcome to the forum

I believe the KTC 19 was designed for external I/O triggers (Horn alert and computer hookup for text and data traffic) However, I have just built a portable repeater using 2 TK880's so its an easy question to answer. I used a surecom 629 repeater controller which is lightweight and designed for portable repeater use. It even has an internal battery to power itself with if you don't have a way to power it directly. The real selling point for the surecom was that they make a plug and play kit for the 880 series radios. the RX end plugs into the speaker port, the TX plugs into the mic port of the TX radio. The entire set-up including a USB charger for the surecom and duplexer all fit into a box the size of an ammo can. Equipment used: 2 TK880 radios (one RX, one TX and note the TX radio should be run at low power to increase the PA's life during continuous operations) 1 surecom 629 repeater controller 2 surecom 48-k1 cables (one for RX one for TX) 1 Celwave UHF duplexer (flat pack) 1 GDS tech USB charger 3A (For keeping the surecom powered during long term operations) 1 6 post fuse block from Autozone 1 Zjelen XHP20 2 pole power connector (to pass power into the box while keeping it waterproof) various jumpers and wires for running power and connecting the duplexer. 1 waterproof box from walmart about the size of an ammo can wireing up the unit is straight forward. I used the fuse block to supply +12V to each radio (each radio has its own fuse) and one post to power the USB charger. I mounted the celwave duplexer first, then using dual lock velcro (the heavy duty stuff) mounted each radio, then the surecom controller. The cellwave used BNC inputs so I snipped off the SO259 ends from the TK880's and soldered on BNC males so the radios plug directly into the duplexer, less connectors and wire = less loss. I then ran a short length of low loss jumper wire to add in a bulkhead "N connector for the antenna. This allows me to operate the repeater with the box closed, thus keeping the unit waterproof. I just ran all the connections, did a little cable management, and I was set. I get about 9.5W out on low power, and about 23.8W out on high power (high power can be used but should be intermittent to prevent PA failure or overheat, remember these radios have a 20-80 duty cycle, thats 20% or 12 minutes TX and 80% or 48 minutes resting per hour on high.) Outside of the build, you will need an antenna, coax, and a good deep cycle battery. I tried an 18Ah battery I use as a backup but I found I only got about 14 hours use if that. So I upgraded to a trolling motor battery which I think was 150Ah, I plan to test that out this week. NEVER USE YOUR CARS MAIN STARTING BATTERY!!! It'll drain it quick and you'll be stuck with a dead car. I know its a lot of info but I hope this all helps. **edit** For some reason MyGMRS says I do not have permission to post pictures here, not sure why. If you would like to see what the finished product looks like feel free to message me and Ill see if I can send em that way!