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I have also had great luck using this method. I also found that in the cases where the metal spring core of the antenna has become visible, squirting some silicon glue into the tube first can be quite helpful. One advantage of using shrink tubing is you can change the color of the antenna, should you so desire. BTW, I have never used them, but there is now shrink tubing available with an adhesive sealant . There are also some types with one sealed end, so they cover the entire antenna.

So curiosity got the better of me while I was doing some shopping online for Black Friday and I found a Kenwood TK-360G for $40 on eBay with a new battery and extra antenna. I know the TK-360G is older, but I hoped it would give me that third data point to see which radio has issues. I also wanted to try setting up a crosslink to Zello to include some non-radio friends/family so I needed another radio As an aside the Zello crosslink is amazing and super helpful for testing. Since I can leave one radio linked to Zello at home and take the other radios with me, I can do all of this testing solo using Zello as an echo device back to my phone (bonus, it records everything for later review). Testing was at low power/narrow since I was only in my neighborhood. With the GMRS-V1 at home connected to Zello, I started walking with the UV-5R and TK-360G. Initially both sounded just fine, but as I reached my normal neighborhood limit where the UV-5R starts to hiss a bit, the TK-360G still sounded fine. Farther out the UV-5R dropped out completely, but the TK-360G went another 1/4 mile before it became unintelligible. Returned home, connected the UV-5R to Zello and did the same test. This time both the GMRS-V1 and TK-360G went about to the point where the UV-5R dropped out before. Seems like the UV-5R was the limiting factor on this test. Third time I connected the TK-360G to Zello, UV-5R went as far as last time before dropping out, GMRS-V1 went 1/4 mile farther. Again, UV-5R seems to have reduced range. I wasn't sure if that was enough data to draw any conclusions, so I set up the GMRS-V1 at Point A (from the original test) on high power/wide with Zello crosslink, then drove over to Point B with the other two radios. With the UV-5R I couldn't hit Point A, but the TK-360G was clear (though a bit choppy at times). Talking through Zello (so GMRS-V1 at Point A was transmitting) I could hear pretty well on the TK-360G with a little static, couldn't hear anything at all on the UV-5R. I drove back to Point A and put the UV-5R on Zello, drove back to Point B and tried again. I couldn't hear either the GMRS-V1 or the TK-360G, nor could either of them hear the UV-5R when I transmitted through Zello. Based on that I think its fair to say the UV-5R is the "issue" here, why specifically I don't know. Some other odd issues I noticed with the TK-360G was that it emits a high-pitched whine (almost like feedback, but it's a constant tone and volume) whenever the UV-5R is transmitting, but not when the GMRS-V1 transmits. Likewise the reception on the UV-5R sounds noisy, almost choppy when the TK-360G is transmitting while the GMRS-V1 receives just fine. Reception on the GMRS-V1 sounds fine when either the UV-5R or the TK-360G are transmitting. I'm not sure what's causing that, but as of right now the UV-5R and TK-360G don't like each other. I'll have to test with my friend's UV-5R to see if it's just my UV-5R. Anyway, sorry about the massive wall of text. It's about as long as my Baofeng wild goose chase

I have seen a few posts talking about getting more distance out of UHF gear, such as the GMRS equipment we use. It looks like the common theme is, many immediately want to go for more power, assuming they can brute-force their way through issues. I am hoping myself and some of the other people who have some training and practical experience can use this thread to help new users understand how to make life better without more power. I want to start with handheld transceivers. HT antennas use your body as a counterpoise. Depending on how you are dressed, how tall you are, how you are holding the radio, the radio position, the distance of the radio from your body, what direction you are facing, all impact performance. Even how much fat, salt and water your body is retaining at the moment impacts how an HT antenna works, because those things vary the conductivity of the human body. In all seriousness, forget about more power... or even more range from a typical HT. If you want more range out of your HT, your best bet is to find higher ground, figure out where the best place to stand is, and what general direction to be facing when compared to the receiving station provides the best communications path. Mobile antennas are often several wavelengths+ in overall height and the body of the vehicle is typically a much better reflective counterpoise. There is a lot that can be done in the mobile and base antenna world that can help, but for now, lets continue to focus on why 'more power' likely isn't the right answer. There is a standard in radio communications about intelligibility of radio communications. It is called the 5/9 scale. 0 to 5 for voice clarity and 0 to 9+ for signal strength in s-units. It is said that while a 2/1 signal provides partially usable comms, the lowest "reliable" communications happens at a 3/2 (or 32) and the best is a 5/9+ (often called 599, 59+20, 59+40). With that in mind, you have to quadruple your power to impact a receiver 1 s-unit. So, if the other party is receiving a signal at 1/2 s-unit while you are using 4 watts, you need 16 watts to go to 1 s-unit. You then need to jump to 64 watts for 2 s-units. Finally a third jump in power of 256 watts to get to 3 s-units and possibly getting a reliable communications signal (a 2/3 or 3/3). Depending on the modulation of the carrier signal and bandwidth, you may need to jump to 4 s-units, requiring well over 1,000 watts. Now, lets say the same receive condition exists, but now you are already using 20 watts for that 1/2 s-unit. Now your power jumps are 80 watts, 320 watts, 1,280 watts for 3 s-units and possibly needing 5,120 watts for 4 s-units. Well, the first bump you made already seriously violates power restrictions in GMRS. AND, this is under hypothetical perfect conditions, assuming nothing else changed in the environment. Which almost never exists. Chasing better performance by boosting power typically doesn't give you any truly desirable results. The top 3 items that will help improve comms in almost every band is elevation, elevation, and elevation. From there its antenna tuning (and beams) filters to reduce interference and lowering the noise floor, as some examples. So, for our technically skill folks... Would anyone like to contribute some general advice for new users to benefit from? General advice on what to do or not to do?

simple and effective

has any one used the id o matic controlers? radio dan has them for about 80.00

While you could do this. For example a sectorized array of antennas. However, I think the theoretical diversity gain would be better letting all antennas see the subscriber. A lot would depend on the topography being served and where portable and mobiles are expected to travel. As I said, this is an experimental idea that I have. In fact the parts are in my lab right now, looking for an appropriate site to test from. I might try three corner reflectors approximating 120 degree sectors to compare. One important thing I want to try is a fourth omni antenna in horizontal polarization. I need some funding and a rooftop!

To replace the lost or broken rubber tip on your portable antenna, go to your local auto parts store, and ask for the appropriate sized "Vacuum line cap" available from carberator parts companies. They're cheap, and do the job of looking nice while keeping the rain out. Silicone sealer makes them rather permanent.

I've used the marine heat shrink with sealant in it, and it's great. When I want a sealed end, whether with or without the sealant I just pinch the end with pliers while the tube is nice and hot. That welds it closed.

have repaired a few antennas using heat shrink tubing worked great and cheap

No need for apology. Like an epic novel, you have us hooked. We are waiting for the next installment of this series. Please continue this experiment, and keep us posted using charts, walls of text, epic novels, whatever. Thanks. Which radios work well? Which don't play nice with others? Where are the weak-links in antennas? You are getting down to what works best for your application, which may apply to others of us as well. This is interesting stuff.

Going from 1 watt to 4-5 watts makes a fairly substantial difference (about 10dB more quieting; I'll test it later) when 1 watt is barely understandable, because the signal gets about 6-8dB stronger. Going from 25 to 40 watts is only a 2dB increase, the same as going from 1 watt to 1.6 watts. There are times when that 2dB advantage makes a difference, but it's so rare that it's not really worth it. FM sees a pretty strong rate of SNR improvement with carrier strength increase when it's close to or just above demodulation threshold, but once the signal reaches a good level of quieting there's almost no improvement that can be made using higher transmitter power. [edit] Here's actual, on-air performance between low and high power near threshold.

FB2 is Single User Repeater FB4 is Multiple User, "Community Repeater", Each user group (Ex: Bob's heating and cooling) is licensed for the repeater pair and their mobiles/portables. FB6 is Multiple User, Common Carrier, Only the system (Repeater) is licensed, users are licensed as part of the system when they become users. FB7 Same as FB6 but non-profit FB8 is a trunking repeater (centralized)

Unfortunately for the old stuff, Vocoder tech does indeed make a huge difference.... enough difference to make DMR sound better at even (arguably) half the bitrate. So it is not about the theoretical max bitrate being transmitted, its about how much those bits are actually encoding useful information, and a better compression algorithm will provide, like MP3, better audio quality at lower bitrates. I like to compare Vocoders to the Fraunhoffer MPEG Layer-3 audio (MP3) which can store audio at 1/10 the bitrate of an uncompressed PCM 16-bit WAV file and deliver near identical quality to that. Sure, an MP3 is still not as good as a 16-bit PCM uncompressed, which in theory is not as good as a true analog LP vinyl 33 RPM, but it takes 1/10th (at 128 kbps rate) the space of a PCM to send nearly identical information to the analog LP signal, and because the brain knows how to put it back together (ECC is in your brain, filling all the missing FFT analysis gaps, etc) you get a pretty much near perfect song. The MP3 codec was far superior to pretty much all of the pre-MP3 era audio codecs that preceded it. and the bitrates needed for an Mp3 to sound great were almost unheard of at the time (1:10 compression ratio in the early 90s was huge, when most consumer hard drives were still measured in megabytes) The same principle pretty much applies to newer Vocoders. Hence why I say, P25 Phase I its obsolete. Much like DMR will be made obsolete once a new Vocoder tech, or something new comes along and renders it obsolete (like Tier I DMR). GSM is obsolete not because of the more sophisticated radio modulations, but because the increased processing power than didn't exist at the sizes of today three decades ago to make such advanced modulations feasible. Newer modulations ranging from OFDM, WCDMA, LTE, QAM.... cell phones can do gigabits per second on just RF... compared to a 9600 baud FM radio the difference is measured in orders of magnitude, that is just ridiculous. So, to sum this long winded paragraph. Its about useful information density, not the bitrate, more bits doesn't mean a better useful information density. Newer Vocoders offer that, older vocoders don't. As for Dual Capacity Diret Mode, or DCDM, it requires no infrastructure to work at all. Please understand DMR terminology (not just read it from Wikipedia) before emitting such statements, DCDM is a simplex Tier II DMR feature and pretty much any DMR Tier II compatible radio I've tried can do it. Even my 44 dollar CCR Baofeng BF-1801 DMR (a low grade GD77 clone) radios can do DCDM, and have two conversations on a simplex frequency. Can't do that with P25 Phase I, nor analog. Again, DCDM is simplex ONLY. Then you can also go with a Tier I DMR on simplex if you want to run legacy stuff, operating the thing on full single carrier, which is obsolete too b/c you pretty much throw away all the benefits that a Tier II TDMA system has to offer. In a Tier II DMR environment you're not limited to having to use a repeater, you can choose what kind of infrastructure use: you can go with a simplex double slot approach, simplex DCDM, or even simplex Tier I continuous single carrier. And then if you need it, you can chose the repeater double slot option too. You have infrastructure options, which you simply don't have on legacy obsolete stuff. Sure, for ham, P25 Phasie I is certainly fine, to talk about that SWR increase of the newest patch cable on the shack, that doesn't matter, but for a commercial customer, having these options, it makes the difference. (also for a family too) ETSI TS 102 361-x (DMR) was designed pretty much from the ground up to replace FM analog. Timing slots are for the radios talking at any given moment, there is no need to create an universal timing for the entire country. At any given site, its either the radios themselves (double slot simplex, or dcdm simplex) or a repeater infrastructure that takes care of the timing, and when interconnecting different sites, either using IP Site connect, or any kind of MMDVM, b/c these convert CAI to IP, those packets get sent over the wire to be rebroadcast somewhere else, so how its timed or modulated back to CAI at destination is up to whatever is being done there. Hence why MMDVM can do all this multi mode "ham stuff", you get the IP packet, retrieve the digital voice information and pack it up as P25, NXDN, Fusion... etc. Also, timing on a DCDM simplex setup (b/c there is no DCDM on repeaters since repeaters operate on 2 timeslots), DMR Tier II radios on DCDM simplex will select a timing leader automatically, and I can see that they will chatter once in a while for a fraction of a second to figure out the timing between all of them, so when you press the PTT, all the radios are already synced up and communication happens. In regard to DMR radio mixed mode, my Alinco DJ-MD5 does DCDM simplex with mixed mode analog+digital on the same channel, and will transmit back on whatever modulation the last received transmission was on just fine: It can listen and demodulate correctly DMR or analog depending on the signal that is being received. There is no "interoperability" with FM problem there, but at the same time I have all the DMR Tier II options that a legacy system like P25 Phase I simply lacks. I still don't understand why range, or operating near threshold is relevant to this discussion? Nobody has argued that having better audio to threshold is bad. DMR has that too.... but FM wideband will still reach further. In addition, RF range can be extended using the right infrastructure, better radios, or both. As for hearing kids on GMRS: here is what happens. First off, I don't hear them breaking the squelch, ever, I never said that. when I hear them is when key my BF-888S running @ 1 watt power, which opens the squelch on all the radios used in the intercom, but if at the same time I am keying my intercom, a 5W portable starts talking, I can hear both radios on the channel. That is the issue I've experienced, which has nothing to do with signaling. Now, when testing DMR all we noticed was a slightly lower audio quality. G.