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I appreciate the flowers... but there are two problems. 1.) I spent 3 years studying electronic technology and engineering. I can describe electron flow to a 5 year old kid at a level they understand. Right now I could start writing everything I know/think that could possibly help in any one given situation, and may finish in time to watch my 3 YO grandson graduate from high school. And I'm not even close to the smartest guy on this forum. There is WAY to much information in my head to share all of it, I don't want to write it all down, and I have no idea what is important to YOU until you ask. 2.) The issue isn't to know when to lead. The issue is for the user to know what direction they want to be led. Then, I can help you 'if' I am qualified to do so. Enter forums... a place were people can come with specific questions and experienced people will try to help. Yes... ^^^ This. We are all here to help, learn and rag-chew about the tech. However, goals, limiting factors and aptitude of the person needing help, makes possibilities endless.

I've been thinking a lot about antenna grounding. I don't live in an area with a lot of lightning but it does happen from time to time. I've been reading on the interwebs about some that say it is absolutely critical but others say that they never ground their antennas because grounding them acts as a bullseye for lightning strikes. I would love to hear from those that are for and against, if possible. If I decide to ground it then what are the best ways to do so and how to keep it budget friendly. My antenna is an Ed Fong encsased in PVC and mounted directly to the side of my house at the roof line with 2 metal U-straps. Thank you in advance.

And... as of today that 'ad' is 404'd...

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.

So, I started my personal GMRS and ham journey in January of this year for reasons that are not relevant here. Among my goals was to be able to have simplex RF comms with my wife at her office. (2.1 miles as the crow flies, through suburban northern Virginia. Small rolling hills, but plenty of RF interference along the way.) Frankly, I was disappointed by the limitations of HT<-->HT around here. I was lucky to make it 3/4 - 1 mile. Clearly, line of sight matters enormously. I got a simple j-pole antenna and tried that at home from my attic. (HOA issues.) Still HT to HT, but no luck. I got permission from the HOA to put up two 5 foot j-pole antennas and got them up yesterday. (See attached photo. Both are Ed Fong designs. One ham and one GMRS tuned.) Simultaneously, I got a 50 Watt (UHF) / 40 Watt (VHF) mobile radio. This morning, I ran a quick and informal series of quick tests with the mobile radio set up in the ham bands (70 cm and 2 m) as a cross-band repeater. (I use a 70 cm simplex channel to my home mobile, which then repeats it on 2 m out to my local repeater (W4AVA).) In short, VICTORY! The repeater connections had several flat spots for me. They're 99% gone now. I can trivially tx/rx to my wife's office location with 5 by 5 audio signal on a simplex connection. I know many folks here dismiss the Ed Fongs, but I have to say those reviews are not consistent with my experiences. In particular, the Warrenton GMRS repeater that is some 40 miles from here was completely out of range for me in the past. With the Fongs on the roof, I'm getting 5x5 signal reports consistently on that repeater -- which serves a vast footprint of NoVA and MD. YMMV. So, yeah, I'm pretty happy with where I am on my personal journey. Cheers, Ken van Wyk WRFC318 / K0RVW

If you wish to put up a repeater, keep in mind that location and height is king. Getting the height (180' minimum for decent coverage) isn't cheap - even if you can find such a unicorn at all... Several years ago I had invested in an off-the-shelf repeater (Bridgecom). I should have checked out possible locations first though. The least expensive I could find was a 332' tower about fifteen miles across the Indiana/Illinois border at "only" $1/foot. The only spot open was at the very top for a bargain cost of $332/month. Ouch! On the other hand a friend of mine has a lovely setup at his mobile home park (he's the owner!) on a 185' tower he erected himself. His repeater has about a 30 mile footprint for mobiles, about 15 miles for HTs.

And there is the problem. There is usually no clear answer as to what the best, or even at times, a good, decision is. There are far too many variables involved. It might be that one excellent solution requires someone with a service monitor to configure, or the ability (and courage) to climb a tower, or deep pockets, a machine shop, and so on. Some users here are computer gurus while others can’t even connect a cable between a radio and their computer. Etc, etc, etc. I for one, have no interest in becoming a leader in this field. On the one hand, the more I know the more I realize what I don’t know. On the other hand, I am completely uninterested is accepting responsibility for someone who blindly trusts in whatever I might opine. At best, I am willing to be a guide or counselor to someone else’s journey into self discovery. YMMV. And that is a good thing.

Aaaaaand speak of the devil... Sunday's Wall Street Journal article, which affirms everything I'm saying! ‘Ready for Lunch? Over.’ Walkie-Talkies Make Comeback With Folks Stuck at Home. Coronavirus lockdowns give the World War II-era device new life

The conceptual idea is sound in that professionals do have the knowledge to design a system for a user or even a class of user however, we all know there are no real "cookie cutter" solutions. While it would be possible to specify some equipment from a single brand that would fit the three (or is it four) classes of user; mobile, base, repeater and possibly the fourth being handheld not every manufacturer of these radios build all the parts needed for a complete installation with the exception of handhelds. Lets look at a typical home or base station setup. First you need the transceiver and a DC power supply with it as very few are AC powered. Next you would need the coaxial cable feed to the antenna and its mount with the antenna being the final piece. Here is where the most customization takes place. You need to know the distance for you coax run and how you will mount your antenna. There is some help on the mounting of an external antenna as the FCC has ruled that building owners and associations cannot deny you the right to install your antenna however they may make and enforce rules about how it is placed. The biggest issues any combo or kit recommender runs into are meeting customer expectations. While some expectations can be mitigated through different mixes of equipment, the biggest hurdle for the consumer will be the price of the kit and the performance of the equipment. Better equipment means a higher end price to the purchaser. That's why the homebrew solutions often work best. Being able to mix and match pieces provides the best path for any user. As different equipment becomes available the user can upgrade different parts of the install. A better transceiver may be able to use the DC power supply from the older unit along with the coax and antenna. The coax could be replaced with one having lower loss for the same distance or the antenna changed, each providing some improvements. There are just too many variables for a system designer to overcome.

I re-read what I wrote, and I agree with you; it sounds really rude! I'm sorry @jonny, et al. Here's what I meant so I should have said this: I'm new to RF and trying to learn, and you guys clearly have vast knowledge on all this. Would you mind educating me without using esoteric terms as to what this is, what it is for, why one would need it, and what it looks like? In holding my feet to the fire, this prompted me to put my money where my mouth is.

Not sure about RF performance, but social distance features are clearly lacking. However, augmented by the death stare. The photographer probably get burns on her hands from her phone.

Jsouth. I would suggest you pick up a copy of the ARRL antenna handbook. It will give you a great insight to how your antenna works, and what you can do to improve both transmit and receive. It also will give you the knowledge you need to build your own antenna. Antenna for UHF 460-470Mhz can be easily made from material obtained at Homedepot, less a few small items you will need to purchase online. The high Dbgain of a directional antenna, it is amazing what can be accomplished. Always remember in most cases the higher you get your antenna the better.

Nice job on the install looks good.

If your antenna can “see” the repeater with an unobstructed line of sight, I don’t see why the 115 wouldn’t work. I have the 115 in my truck and can hit repeaters easily at 12-15 miles using the stock antenna. Amateur radio operators talk to the ISS with 5w Baofengs, so it’s not all about wattage. I would check your SWR first. Should be less than 1.5 if possible. Other than that, you could try a Yagi antenna and focus all the RF towards the repeater and see if that works. Best of luck and 73, WREX979 KO4CWG