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Everything posted by WRKC935

  1. OK, while not trying to make this overly complicated, I will only mention these concepts and not the math behind them. First off is that 3 dB of loss is meaningless when you start looking at the overall effect it has on the range of a radio system. Consider that a CB or ham radio with an S meter registered S-1 to S-9. The change of one S unit required the signal to change 6db. So if you were running 10 watts and were being heard with an S-8 you would need to increase your power to 40 watts to bring the meter up to S-9. And what did that really do to the overall signal quality? Not much. Here's the thing NO ONE ever brings up and involves the most math. Path loss. Path loss is the signal level loss though free space between the transmitting and receiving antenna's. And it's going to be over 100 dB. And this it where people fall flat with the idea of cable loss and antenna height. Path loss can indeed be calculated and the attenuation levels changes depending on the medium. The other this that no one takes into account is horizon. UHF signals do NOT bend in the atmosphere. They radiate in a straight line away from the antenna and once they reach the horizon they keep going straight. No amount of power increase will change this but a height increase in the antenna does. The other thing that the height increase changes is the medium that the signal is required to pass through. Meaning if your antenna is 5 feet off the ground, the signal coming from it has to radiate through trees, houses, buildings, and the minute it hits a hill it's done going that way. All of these objects attenuate the signal of block it completely. A typical building is going to be over 30dB of attenuation. So if the building is 90 feet tall, and to get over it requires a 3 dB loss of signal to radiate past it, then you loose the 3 dB in the cable to make up for the 30 dB loss trying to pass the signal through the building. Yes, you can over so it and place an antenna too high in the air. But unless you have a 1000 foot tower this is a topic NOT worth discussing.
  2. 30KW plus. The actual setup for many of these is a special custom wound plate transformer that takes a very high amp alternator and connects the 3 phase output that is typically held to 50 or so volts and steps it up to a proper plate voltage for the tubes they are running.
  3. Alright. Since I am the guy with the tens of thousands of dollars setup and the commercial install I believe I need to interject here. Never did I say that a small repeater system is useless. And there are COMMERCIAL repeaters available that ARE indeed two mobiles in a box with a controller between them. And those work find if that is all you need. My point was if you are going to put up a big commercial grade install that you need to NOT pull the crap of wanting fee's paid for access, as this level of install has a huge footprint that will interfere with other repeaters on the same frequency in that footprint. And the frequency resource is limited for repeaters. I am all for guys that want to put up a repeater on their roof or short TV tower and be able to talk 8 or 10 miles. This sort of thing SHOULD be encouraged. But you still need to be aware of others on the frequency and try to find a quiet pair to set your repeater up on. The other thing that needs to be said here is IF you are going to stick an antenna WAY up in the air and cover a 60 to 80 mile radius, you DO need to have good commercial equipment and not two portables with a back to back cable between them and a cheap duplexer. And here's the reason. If you are the only one that will be using it, and the usage is light, it don't matter. But with a big coverage footprint there is a good chance that it will see a lot of use and portable radios are NOT designed to be run at that duty cycle. The commercial repeaters I use for GMRS are 100% CCS (continuous commercial service) rated. This means they are designed to be transmitting up to 100% of the time, 27/7/365 and live. If you were to try that with the two back to back mobiles the transmitter would not survive the abuse, even with a fan and additional cooling. Now, my repeaters are only logging 30 to 45 minutes of use a day currently... but that number keeps increasing. And that's fine. I built it to run all the time, and offer it for free to all licensed users in the coverage area to use at their leisure. But I would hate to see someone put in inferior gear at some remote site and it die when it was needed. That situation is actually worse in my mind than it not being there at all. Because if it's needed and expected to be operational. And that operational repeater is part of someones emergency plan, then it needs to work as such.
  4. IanM brings up a lot of good points and I am planning on putting together a sort of HOW-TO on frequency coordination. I will say that it would take cooperation form the GMRS community. But, if that cooperation could be obtained, it would work out well for all involved. In fact, it's something that MYGMRS.com web site could possibly host the data for so that it would all be public and guys could look at it and hopefully administrate it. There is a coverage mapping software that runs here now, but far as I know it ONLY shows the footprint of the specific repeater you are currently viewing. I hear the comments about being limited to 50 watts. Well, here's the thing with that. You are trying to communicate with portables that are 4 watts and mobiles that are 10 to 40 watts typically and have antenna heights below 10 feet. I have two repeaters on the air currently. One is 40 watt and the other is 50 watts. They both have a coverage footprint that extends over 30 miles in some directions. And because of the antenna system I am running. One transmit and one receive for up to 4 repeaters. The loss in the transmit combiner with 50 watts in means I am getting about 12 watts coming out of the building headed to the tower and antenna. And I cover over 30 miles.
  5. Couple things here to the guys that JUST got their license and are trying to make a contact. First.. POST YOUR CALL SIGN. Second .. POST YOUR GENERAL LOCATION If we don't know who you are and where you are then we can't really assist you with where an unlisted repeater might be. You could be our neighbor and we don't have any idea. My call is my user name here. But that is easily converted to Keith Foor and my address since the FCC posts that info. Once we know where you are we can tell you about repeaters that you can access if we are in the same area and any specific programming that they might require.
  6. Yes, connect a ground wire to it and then wrap it with butyl and vinyl tape to weather proof it. Make sure to properly connect the other end of ground wire to a proper ground.
  7. You are right, depending on the cable run length and how often you want to change out the cable. 400 is kinda lossy if it's over 100 feet.
  8. I put 1/2 heliax connectors on for years with nothing but a pocket knife and a couple cresent wrenches to tighten the connector body down. If you are using Andrew / Comscope connectors they come with a guide for doing this. Follow the directions and you will be fine.
  9. I want to thank JeepCrawler98 for pointing out the ID requirements for a repeater. If you are the ONLY licensed user and the repeater is closed to all others, and everyone uses YOUR call sign legally under the rules then it doesn't have to ID. If anyone else uses it, it needs to ID. And in truth, it's just easier to have it ID. Now for those that don't want it to sit there banging away every 10 minutes with an ID, use a commercial repeater and allow the repeater to ID through the programming. This will be at a set interval as long as the repeater is active. Meaning that if no one is talking on it, it's doesn't ID. That is within the regulations. I have heard HAM repeaters that bang away every 9 minutes. In fact I have one local to me that has two ID mechanisms in it. Both are voice. They are set at 9 minutes and 8 minutes. The 9 minute one is EVERY 9 minutes without fail. The other one is active only. But you can all but have a conversation with the dumb thing because it talks so much. DON"T BE THE GUY WITH THE HAMMIE NONSENSE TALKING REPEATER on GMRS. That is unless you really don't want other people to use the repeater. ANTENNA LOCATION So you have gathered a bunch of parts together and now you want to put your repeater on the air. Question is where are you going to put it. We discussed that antenna height is KEY to how far will it talk and hear. If you put it on your garage roof, it's gonna talk a few miles but nothing crazy. If you want to have the big dog, you have to have have a big tower. Now there is software that is online called RADIOMOBILE that will plot coverage maps out for you based on the info you put in and maps that it pulls from the Internet that I have found to be reasonably accurate. You key in all the info and it pops out a map. And because it's computer based, and you are controlling it you can create maps with different antenna heights and locations that you can reference. I will tell you this now and save you the headache. For the most part, if a tower is owned by one of the major tower companies, they are going to want at a minimum 1000 bucks a month for access to hang an antenna. Will require you to hire an approved tower company to install the antenna. You will probably be required to get your own electrical service and carry insurance as well. Now there are exceptions to this as well. I currently have the ability to put up all 8 repeater pairs via the antenna system I have. I run a receive multi-coupler and a transmit combiner. I am currently only hosting two of the 8 pairs on repeaters. I can't say that I am the only person in the entire USA that would do this, but IF you need hosting in central Ohio, have a name brand repeater that is RACK MOUNT, and are willing to cover the bit of additional electric, I will host it on my tower. That being said. AGAIN, if YOU have this sort of setup, you should be willing to do the same in my opinion.
  10. The next bit is the duplexer. And there are a number of options here as well. The point of install is going to set the requirement for what gets used. The little flat pack UHF duplexers are very usable on GMRS in certain instances. Those are going to be the smaller installations on a relatively short town (under 100 feet) in an rural setting or maybe a suburban setting where there are not a lot of other repeaters near you. These duplexers work on a frequency reject configuration where the input side rejects the output and vice versa. There isn't a pass component to this style duplexer, which means that the specific frequency and a few kilohertz above and below it are blocked but EVERYTHING else is passed through. This becomes a problem for installs where the antenna is receiving a number of other things, both UHF and elsewhere on the band and allowing that RF to get into the receiver of the repeater. The reason this is a problem is the first amplifier in the radio receiver string can only handle so much signal before it gets swamped. For a quiet area, it's not a big concern. If you are at a tower site with many other transmitters then you will need a pass/ reject type of duplexer where the frequencies of interest (TX and RX) are the only frequencies that are passed through the duplexer and everything else gets rejected. ANTENNAS and HEIGHT Here's where the distance that the repeater is going to cover really gets set. There are some folks that will tell you power level is everything. I am here to say that's false. I have a repeater system that I maintain for my employer that can be heard 60 miles from the transmitter site. And it's turned down to 20 watts coming out of the repeaters. The antenna height is over 500 feet however. And it still talks farther than it can effectively hear. Add to the 20 watts the fact it goes through an 8 port combiner and looses another 6 dB of signal level and is feeding 650 feet of cable (more loss) and it's only getting about 6 watts to the antenna connector. Point is that if you really want to cover a LOT of area, height is key to doing so. But know that you are NOT gonna be able to run LMR 400 or 600 up a tower like that and have good results. Cable loss is figured in dB per 100 feet or 100 meter lengths. If you look up what cable you are using, it will have the numbers for the frequency range that you are operating on. This is important on long runs. Anything longer than 100 feet for UHF really should have 7/8 cable at a minimum in use. Getting to the antenna. I have spoke to people that were looking at using some mail order antenna thing that you went to a hardware store and bought PVC pipe to build the antenna. This might be ok for your home base station or repeater. But I have built these types of antenna's and they doing hold up for very long. Find an Andrew / CommScope or other commercial antenna and use that for a repeater. You will have much better luck and will be happier when you are not needing to replace the antenna every 6 months because the wind broke it.
  11. It's possible. But it's most likely stupid expensive and totally out of reach. Unless you are on a mountain top and are moving to another mountain top on the other side of a valley. GMRS radio operates line of site. So you run into the horizon at 10 miles typically. This varies some, but is a good point of reference. To overcome the curvature of the earth we use towers. So to add 1 mile of range, you need 25 foot of tower past the horizon. So you either stand up a REALLY big tower at one end, or you split the difference and fine a tower in between because talking 50 miles might only require a 200 or 300 foot tower. Remember you ask if it can be done.. It can. It's also gonna cost a LOT of money. Your other option is HF ham radio, and NVIS antenna's at both ends. Of course EVERYONE using the radio would need their own ham license. Personally I would just get a cell booster, stick the donor antenna 30 or 40 feet in the air and point it at the nearest cell tower and put the other antenna in the house. Then the cell phone works and you can communicate with everyone and not just family.
  12. Go pop some popcorn and kick back.... This WILL be a long read. So you have you license. Now you want to put up a repeater. Great,,,, maybe,, usually. But have you thought it through or do you just really want to hear your call sign coming across the airways if CW? This is going to explain how to do it right to NOT cause interference with other repeater owners and be mindful of the limited resource (8 repeater pairs) we have been designated by the FCC. This will cover planning, equipment, antenna's and everything in between. Please ask questions about the topics as they are posted, and if you see something missing you would like covered, message me and I will do my level best to cover that topic. I have been a commercial two-way radio tech for 13 years a ham for almost 30 and have been working on electronics and radios for 40 years. First thing is to listen. Listen to the repeater pair OUTPUTS. These are the 462 frequencies in the 462/467 pairs. They are what the repeaters will be transmitting on. The reason you want to listen is you want the quietest one for your area. Now that doesn't necessarily mean the one with the least traffic. So if you have several repeaters around you that are not all that busy, but the signal from them is always very strong and clear and maybe a busier frequency talks alot, but is far off in the distance 4 towns over, any your plans are for a small footprint, with a 30 or 40 foot tower, that may well be the better frequency to choose. You need to consider a couple things here. Number one is the total number of pairs available. We only have 8 for EVERYWHERE. Why is that important? Because the guys with the monsters, like me how just talked to a guy 40 miles away from his repeater, can cover huge area's with their repeaters. And some of them see the value in what they have and allow others to use it openly. That's my stance on it. I say the same thing to everyone that asks. Make sure to ID your station and have fun. But if you are sitting on an otherwise open frequency, he may not use it for a wide area coverage machine. I am thinking on writing a thread on frequency management at a state level for GMRS, but that comes later. So back to the footprint you are looking to achieve, and you need to be reasonable here. Don't decide to build a monster, tie up a pair and make the repeater closed to all but you and your wife and kids. That's not proper use of the airways. And in my opinion is a bit of a dick move. SO lets say we are going to use that pair that you can hear a repeater on but it's very weak signal and can't always be heard. You NEED to locate the owner of that repeater and verify where he is located. If he's a weak station but he's right up the road, then don't use that frequency. If he's 2 counties away, you are golden. You need to find out what PL or DPL he is using on his repeater and NOT use anything close to that. If he's running between 67 and 103 you want to be at a minimum at 141.3. This will minimize the potential of interference. You also need to verify that you are either very noisy into his repeater or you can't hit it at all from most of the footprint area you are wanting to cover. Now a quick side note. Repeater talkout (how far it talks) is controlled by two things.. first is antenna height. Height is FAR more important than power level. But power level does play a role. And you ONLY want to run enough power to provide signal levels in your desired coverage area to capture the receiver of a mobile or portable radio. Meaning, if you are wanting to cover X number of square miles and that can be done with an antenna at 40 feet of height and 10 watts, Don't set the repeater up to 50 watts. It's not necessary and again, it's not good frequency management. So you now have a pair picked out. What about a repeater? A repeater is required to ID unless YOU and those under YOUR license are the only ones using the repeater. The minute that other license holders are allowed to use the repeater, it needs to ID itself. Now this can be done with a Raspberry Pi, an Arduino or some specific module for CW ID. You have options. You can use two mobile radios as a repeater with a cable between them and an ID board. You are not required to have voice announcements, roger beeps or any of that. So it can be a simple set of radios. (Motorola CRM series work great and the 16 pin interface makes connecting them very easy). Or you can buy a repeater that is a purpose built device. There are a number of options. More to come.... stay tuned.
  13. Have you figured out who I am? Geeze,,,, I just looked up your ham call. That's not the one you had when we were all hanging out on the 24 years ago
  14. So I did talk to a guy in Marion Ohio today on the 675 repeater. He was mobile, with a 15 watt radio. So the coverage from the site to the Northwest and North seems pretty good.
  15. And this folks is what happens when someone asks something that they should KNOW the answer to..... like "if I transmit DMR into an analog repeater, will another DMR user hear me" which should be obviously NO. And at that point, one would have to assume the other person or people in the thread will assume you know NOTHING of radio and the underlying technology OR you do know and are asking really silly questions to irritate the folks in the thread. Then we need to retort by talking about all the effort put forward to further GMRS and it's users. The TWO HUNDRED dollar a month electric bill, hosting TWO repeaters on the site,,, or the taxes, building upkeep, repeater upkeep, overall mundane site maintenance like mowing the grass. Na.... I don't do ANYTHING to contribute. Not one damn thing. And while the two GMRS repeaters are NOT the only radio equipment on the site,,,, the fact its' done for FREE. Well don't see any effort there. Whats wrong with subscription fee's??? You're gonna ask ME that. The guy that has two repeaters that cover 7 counties in Ohio that are free to use by ALL what's wrong with fee's. Simple, if you can't afford to have a repeater on the air,, take up a limited number of repeater pairs, and think you should be somehow entitled to MONEY for your effort... well screw you. That's whats WRONG with FEES. Go spend 48K on a tower site. 1800 a year on taxes. 15K to rehab the site. Then put a GMRS repeater on the air FOR FREE and support all this out of pocket and then question me about fee's... I have tried to be nice... I am done with that. You don't like me... fine... You don't like what I have to say... don't read my posts. You want to get on my thread, and ask stupid questions that my WIFE actually laughed at because SHE knew you can't TX DMR into an analog repeater and have it come out the other side as DMR. NO,,, I am gonna call you out on it. I brought up post counts because if you were some noob with 5 or 10 posts, the question is relevant and you would be deserving of a real explanation. Not the case here. Oh, BTW,,, she is an accountant. I am the professional radio guy. She's just been around it enough to know better. Only chimed in... but are done with ME and the thread. The what the hell are you still posting for? You said you will stay out of my lane and ask that I stay out of yours. So I said NOTHING and stayed in my lane. PAY ATTENTION,,,, YOUR TURN SIGNAL is STILL on from the lane change there bud. Here you are.... back in my lane. So at this point... this whole thing has been hijacked. It needs closed or deleted.
  16. Enough. You have 272 posts on here... do you ever read what others have said? You certainly can't be that obtuse. The guy has a for profit business hosting GMRS repeaters that you have to pay a fee to access. He has a list of at LEAST 20 repeaters on this site through out central and southern Ohio. Some of them are at tower sites that I can say for a fact he has ZERO access to. And I have been in them and NO GMRS equipment exists at these sites. And when I say business, I mean established business with a State of Ohio issued business license, tax ID number and these documents indicate it's a for profit business. Which if you had read the rules pertaining to GMRS and fee's you would KNOW that's illegal. Now, how profitable his business is. How many actual subscribers he has. The real number of repeaters he has on the air. I have zero clue on any of it, and don't care. But specifically to the "whats' wrong with that?" question.... it's against the FCC rules. Using DMR or ANY digital modulation (MDC and other positoning data transmissions are NOT digital modulation) is against the regulations for GMRS. And since I know someone will disagree, you are allowed short data bursts for ID and GPS location, but they are analog modulation of digital data, not a digital modulation as defined by the emission designation . And I am thinking that we need to get this thread back to the original topic of the tower build out.
  17. I think I was pretty clear here. A DMR radio will not be able to TX into an analog repeater (required by FCC rules pertaining to GMRS). The repeater would need to be a DMR repeater. I am curious if you are trying to shine me on... or if you really don't understand radio systems any better than you are indicating? If you don't know.. that's OK. Having a GMRS license doesn't require any technical knowledge of radio, like ham radio does. But I am not sure I can explain this enough if you don't understand the difference and why it wouldn't work.
  18. NO that is NOT what I am saying. The only way that works is if there is a DMR repeater programmed for that frequency and color code you are on. If the repeater is analog ONLY as the FCC rules require then they would NOT hear you transmitting on DMR. Whats' more that is illegal to do, so I wouldn't advise it.
  19. That's interesting that they don't seem to care. I ain't gonna lie. If I could run DMR on GMRS, I certainly would. Well actually I would prefer to run P25 on GMRS and AES encryption. But the rules say no... so No.
  20. I haven't made any attempt to decode it with a scanner or service monitor and get the CC or Group Call ID numbers to see what it is for sure. I would hope that it was clear. But figuring that it's DMR on GMRS which as you pointed out is illegal, going the extra mile and encrypting it wouldn't be a surprise. I can't remember if I am hearing it on 625 or 575 but I think it's 575. I may throw my Whistler scanner in the van and see what I come up with at some point. The other thing I would like to figure out is if it's a repeater or just a subscriber. I would guess it's a repeater because I hear it from Columbus all the way to Mt Vernon.
  21. Nope,,, it's happening. I would venture a guess that the guy that is running the GMRS pay to play business is the one doing it, but I don't know that for certain.
  22. To be honest here. Once the 35 dollar GMRS license actually goes into effect, I never read where you can't purchase a license in another persons name and gift that license to them. Obviously I wouldn't expect folks to be buying licenses for everyone they are acquainted with. But for those that show a real interest in it, and for those that have the means to do it. I don't see a reason NOT to if they are unable to for any reason short of being banned from having a GMRS license (due to felony convictions and the like). I don't see GMRS being ham radio. And I hope it never goes that way. And in truth, I wish that the ham's that got licensed for purposes OTHER than the true nature of ham radio like SAR and such would have gone the GMRS route instead.
  23. I believe I need to say this after the Darth Vader post before. Here's my personal take and my situation. Most of you are NOT going to be able to park an antenna system 240 feet AGL and 700 feet HAAT and connect your repeater to it. I can. Most of you are NOT going to have a multi-port TX combiner that allows you to connect MULTIPLE repeaters on multiple frequencies to one antenna. I have that as well. Most of you are not going to have a stream of faulty equipment that you have the knowledge and equipment to repair and put on the air and instead need to purchase new or used hardware that honestly ain't cheap. Again, perks of being a radio guy. Some folks will say it's just too old replace it, so I do. I ask what they want done with the old stuff and remind them it's technically classified as hazardous waste (due to chemicals in capacitors and the lead based solder) and they request we dispose of it. All that being said. If you had the ability to park an antenna that high. Cover 7 counties with your GMRS repeater and have that level of coverage, you no doubt would but it's not in the reach of many. For me it's right down the road, so I do it. And the fact that's it's NOT on a 40 foot TV tower in the back yard and can only cover the two closest towns and no further, I feel it's my responsibility if I am gonna occupy the frequencies that I need to allow EVERYONE that is licensed and operates within the rules to use the repeaters I provide. So I do allow everyone. I closely follow the laws. I do have others around me running DMR on GMRS, Selling access as a for profit business (his business license attached to his GMRS site indicates its NOT a non-profit) I refuse to do either. If I want to sell air time,,, I will go get an FB6 or market frequency (would need it due to footprint) and sell air time on a commercial community repeater. I ain't into that though. Don't think that since I do this, you need to do the same. But if you DO decide to put your GMRS repeater system on full send and cover 7 counties with it, remember that you ARE creating interference for others that are not. And in doing so, their repeater on a 40 foot tower becomes useless to them as you overpower it when your repeater starts to transmit. That guy SHOULD have access to your system because you are denying him access to his stuff. Or at least interfering with it a lot. I have worked with and continue to work with the local guys. We have put together a band plan, I have setup duplexers and repeaters for those guys to interleave their channels with my efforts to minimize interference. And I will continue to do so.
  24. Update to this build out. At this point. I will not be building out 625 or 575. I have encountered both analog and DMR repeaters??? on these frequencies in the coverage area that the system exists in. The coverage footprint would be identical to the repeaters I have on the air at 725 and 675 and this would not be fair or reasonable for those system operators to attempt to compete with my coverage footprint. If those frequencies clear at a later date and no other repeater exists on those frequencies, or I am approached by those system owners wishing to plug their repeater into my combiner and share my antenna system. I have zero interest in interfering with other open systems. And I will work to maintain coverage for other GMRS users as long as there is a perceived need. At this point I am going to redirect my efforts at setting up the dispatch console and the resources for it. And increasing the HF antenna performance from the site.
  25. Another option that is NOT that tape is what they are doing now with fiber runs down a tower. You tape the line down with 2 inch tape then wrap it with 3/4 fiberglass packaging tape and then wrap that with more of the 2 inch tape. The fiber glass tape is as strong as the aluminum tape and is easier to work with. That 425 tape will cut the snot out of you if you are not careful with it.
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