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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 Real-world receiver sensitivity (which may or may not be published accurately).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

Correct. Here is an example. If you are programming for what many would call a ‘550’ repeater. Your radio would be tuned to 462.5500 MHz (this is the the frequency you listen on). Your radio would be configured to transmit +5 MHz higher on 467.5500 MHz. This is called a 5 MHz positive offset. Michael WRHS965 KE8PLM Sent from my iPad using Tapatalk

"So if I got this right, if the number after output is say 462. that is the frequency my radio should be tuned to? I'm sorry I'm so dense. Science is my weakness." Yes and No, Yes, you should be tuned to the 462 frequency. Your radio should also be set with a +5.00 offset. This allows your radio to transmit on the 467 frequency. Thus, technically, you should be tuned to both frequencies at the same time.

Glad you figured it out, I was about to mention the off hook decode/scan. Basically with off hook decode is disabled, if the mic is in the hanger it'll require the correct DCS code to break the squelch however with it off the hanger it'll open up for everything. This is meant for companies running 2 or 3 user groups on the same frequency so you know the channel is clear before you transmit. I don't know of too many other applications its used for.

I think this topic has been sufficiently discussed. We are very near the point of running into Godwin's Law.

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.