Jump to content

WRKC935

Members
  • Posts

    848
  • Joined

  • Last visited

  • Days Won

    17

Everything posted by WRKC935

  1. I don't think ANYONE was actually talking about repeaters on MURS. Michael needs something to comment on in every post he see's. If he can't find it he will try to make something up. We were discussing a different topic all together. Yes, we hijacked the thread. Talked about commercial radio stuff, not MURS. My advice Michael, go down to the Home Depot, Lowes or whatever home improvement center you prefer, get some lumber, hammer and nails. Drag it all home, and build a bridge, so you can GET OVER IT. If that is too much to handle. Go to the toy store, find Lincoln Logs. There were plans for a fine bridge in there. Knock yourself out. You can feel some level of accomplishment that you created something worthwhile.
  2. That makes more sense. We just issue a request for frequencies for the site, go monitor what the coordinator gives us back as possibles and pick one. But we RARELY are building systems like that anymore. 95% of what we are doing is public safety on a state wide system, the other parts are repeater systems for small and medium business typically warehouses for coverage inside the fence, malls and stuff like that. I guess having a state wide system for public safety has made us lazy.
  3. It's interesting to go back through a thread and see what you missed. Mark, you are charging 3K for licensing fees BEFORE the 500 for the coordinator. I guess we need to be charging WAY more for that. We just charge the 500 plus markup. Malls with 70 watts ERP. That is a failure of the vendor pure and simple. The ERP on the license is a NOT TO EXCEED amount of power. If they NEED to be running 70 ERP, then you configure the system to do that. If they only need 10 watts ERP then the vendor should be turning down the power to that level and doing range checks to see that the coverage meets the customer requirements and doesn't go any further. If you aren't doing that, you really should be. I come across a BUNCH of that chasing interference issues. Of course the problems arise when you attempt to talk to a frequency owner that is causing interference by running more than their legal ERP (happens a BUNCH) or they are excceding their needed coverage area. The first one is simple enough to deal with. If you can prove out the excessive power with a field strength vs distance calculation it all gets submitted to the FCC and they put a letter in the mail to the license holder of record. Vendors RARELY take into account the true ERP when they put up an antenna system. They will park a DB-420 in the air with 9 dBi of gain and have 40 feet of feed line feeding it with a 100 watt radio. Figuring for cable loss and duplexer loss they are at 70 watts to the base of the antenna and their ERP is actually 560 watts. Not taking into account HAAT gain. Which outside of broadcasting, NO ONE does and is NOT required due to antenna height being on the license. Antenna's Rarely are above the listed max height the license, but that does happen at times as well. The other thing no one mentioned here is the radio enthusiasts that have 110 watt radios that they wanted to fill with frequencies. And the MURS, FRS, GMRS, and Itinerant frequencies ALL go in them at full power. Can't tel you the number of high power Spectra and Astro Spectra radio's I have seen that had that stuff in them programmed at 100 watts. Connected to a high gain HAM antenna in their vehicles. I don't see much of that from vendors, it's typically ham's and other radio guys that are doing it. And really don't understand they can't or don't care. They will print off a frequency chart of Itinerant and license-less frequencies and go to town with putting them in their radios.
  4. Band opening. Happened last night too.
  5. OK, I might have missed that you said that. They do tend to run warmer that you would expect them to, especially when they are dormant other than being powered on.
  6. Yeah, they do run a bit warm. Might be worth having a shop do a FULL alignment on it and make sure they do the PA bias alignment but I know those radios would get warm sitting on antenna doing nothing.
  7. As a linked repeater owner that DOES run 24/7 linked, I agree with what you are saying. The problem is how to deal with it. I have 3 machines on the air off the same tower. The one 'belongs' to the tower owner and is public but we tend to steer folks to my local repeater for local comms. That one is the 675 repeater. The coverage of all three repeaters matches. SO there can be 2 different conversations in progress at the same time. Then there is the 600 which is the linked machine. I knew going in from previous experience with HAM that the linked repeater needed to be backed up with a local machine for when folks wanted to just chat locally they had a way of doing so that didn't involve 30 other repeaters. And I ensured that was what happened. I have made it very public that the linked machine was for conversations that were wide area involving more than one machine, and if users were hearing the same reset tone, mine are different between linked and local TX source, they needed to move off to the 675 and talk because they were tying up 30 repeaters to talk 10 miles. And the users have always been happy to do that. I did look at adding a repeater for the other linked system, but decided that was a bad idea. First off they wanted money from ME to grow THEIR system. If I was running some simplex node with an antenna 20 feet in the air, I could MAYBE see that. If you go look at the Johnstown600 in Ohio on the maps, you quickly realize that's NOT the case. So I scrapped that whole idea completely. At this point I am looking to GROW the coverage of the MidWest system with additional sites and repeaters. But the plans are to install TWO repeaters at every site. One will be linked and the other will be stand alone if possible to provide a local radio resource for users to talk in their area without tying up the whole system. That may not be possible in every situation, and when that's the case the repeater will be linked. But I am looking to provide coverage foot print by design, so I will avoid putting repeaters up in area's that someone has linked coverage for the system in, including myself. So the sites will need to extend coverage footprint of the system overall. Right now that's not hard as there are only two of us that have linked repeaters in Ohio. Mine that covers the Greater Columbus Area and the Findley repeater that covers a portion of the Northwest part of Ohio. But going forward, that will change, and I will not 'compete' with standing coverage. To me this is not a contest, it's a service. And I would hope that others see it the same way. I know the guy in Indiana is doing his that way. Sure there is SOME overlap, but there is gonna be some overlap. You want a bit of overlap to eliminate dead spots. But you really shouldn't double cover any area, it wastes the limited frequency resources we have.
  8. If it's JUST your family then you are legal as long as they are identifying. But it has to be private use, meaning your family is the ONLY users on the repeater. If ANYONE not covered by your license is on the air, then the repeater needs to ID in some manner.
  9. The issue with a non-current regulated PWM charge controller is the state of discharge when the sun comes up or the winds begins to blow in the case of a wind system. What happens is the cheap charge controller will apply the float charge voltage value to the battery. Depending on it's state of discharge, that can be a current below or ABOVE the maximum rate of charge for the battery that's connected. Couple ways around this, but it WILL effect the charge rate if you overdo it. If a single 7Ah battery needs 2.5 amps maximum of current being dumped into it, if you put 4 of them in parallel and charge them with a 10 amp source, then they are only getting 2.5 amps PER battery. But that maxes out the source current, and leaves NOTHING for doing anything else like charging phones or other tasks. So you really NEED a good charger to do it right. But there is another issue with charging batteries. And that's just trickle charging them when they are depleted or significantly discharged. Batteries also need a minimum amount of charge current to charge them. Not providing enough current is almost as bad as too much current. And of course, they will not typically recharge completely in the window of time you have the secondary charge source working IE wind or sun. And NEVER leave a battery open circuit for an extended period without charging it. THat will destroy a battery. I have a string of very large and heavy two volt lead acid batteries that this was done to. I am going to TRY to dump current into them and see if I can get them to charge, but I am not hopeful that will happen.
  10. Where are you at in Ohio? Email me, mycall sign at gmail to discuss the repeater.
  11. Yeah, I have had several of these that I have worked on. Kenwood turns off the oscillator when they are not keyed. Motorola, Vertex and some others just turn the PA on and off. It allows for a quicker keyup time if the oscillator is already running on frequency. Now that delay isn't typically very long, but with trunking radio systems it can have an effect. The other thing is if it is still locking on frequency when the PA turns on there can be an audible tone heard on the air as the frequency stabilizes which can effect the signaling the transmitter puts out to the subscriber radio letting it know it's on the channel and transmitting. That stuff happens pretty quick but any delay is still a delay that the user can see and complain about. ANd if it effects the outbound signaling word on the trunking system, the call can be lost by the subscriber.
  12. Obviously you missed this since we are still discussing it. It's NORMAL. That's the way the Vertex works. And Vertex isn't the only repeater that does this. Some others strip the PL. MTR's and Quantars have a programmable REST frequency they revert to when they are receiving so this doesn't happen in situations were the repeater is located close to where portable radios are going to be. But again. This is normal and expected. Look in the programming and see if there is a setting for a REST frequency. If there is it's probably set to the TX frequency of the repeater. Change it to something else but DO NOT set it for the receive frequency or it will interfere with the receiver of the repeater. Once the issue goes away, program a radio up for to receive the rest frequency and you will find that it will hear the repeater generating a signal on the rest frequency. And when you key the repeater, the signal will go away. Or you can continue to connect and disconnect your antenna's, walk around the house and see where you can hear the signal. Ask more questions and get told more nonsense about what is NOT causing it and continue to wonder what it is. Even though I have told you. And since I believe I am the only one on here that does this shit for a living. I just might know what the hell I am talking about. Maybe... But at this point, it's anybodies guess.
  13. The repeater is constantly generating low power RF with PL by design. The final PA is turned on and off to facilitate actual transmit. You are picking up that RF signal and it's opening up your radio. This is completely NORMAL and is not a concern. MTR and Quantar repeaters do the same thing.
  14. Things that you will face being 'close' to an airport. First is height restriction. Now what that is will have to do with where you are with regard to the direction of the runway. If you are off to the side, it's not going to be as restrictive as if you are at the ends of the runway. Second thing is distance from the runway. There are calculations that the FAA will do to set your maximum height allowed depending on these factors. Second thing is obstruction lighting. You will probably be REQUIRED to have obstruction lighting on the tower and if that's the case, you WILL be under constant scrutiny to make sure it's working. And understand that the fine for an average tower is 4K a DAY for that light not being on. And they will be watching. You will be required to have the light monitored and as soon as it goes out a NOTAM be issued that the light has failed. Failure to issue the NOTAM is another fine. Again, lots of money. Actual FAA approved obstruction lighting systems are expensive. I just looked at one that was 15K for a single light. And that was without installation. What's required is going to be dependent on what the FAA tells you is required. And if that's the requirement, then that is what HAS to be used. You can't do whatever red flashing light you can afford, you have to use what they tell you to use. You are probably going to need to install a generator so the light works during a power outage. Since the monitoring of the system has to work 24/7 no matter what, you would be well advised that if you are required to install an FAA approved obstruction lighting system that it have a generator to run it. Electrical requirements. Our lighting system puts the electric bill at about 80 bucks with NO OTHER equipment running. So it's a hit on the electric bill to burn the light. Your mileage may vary, and the new LED systems are more efficient than the old strobe systems like I have but it's gonna make your electric bill go up. Lastly. It WILL decrease your property value. If there is a tower on your property that requires constant electricity, has the potential to create HUGE files from the government and is an eyesore to many, selling your house will be more difficult. And once the tower is up if it requires a light it will require registration with the FAA / FCC. Which means government inspections are possible, and if it's that close to an airport, you will get a yearly inspection. And you can't just tear the thing down either. You have to file paperwork with the FAA called an intent to deconstruct. Once the tower is down you then need to finish that paperwork out and file more paperwork to indicate the tower is gone. Failure to do all that if the tower has a registration number is also a fineable offense, so more possibility of getting fined big money. In short, you need to talk to the FAA, see what's required, and if there are requirements, forget it and move somewhere that there are less requirements.
  15. Yes, it's a fair and reasonable request. And in truth it's reasonable to expect people to actually do some homework and find either an open repeater pair, or to program a PL into their equipment so it's not interfering with gear that's already on the air. I assume since you are gun shy to let us know who this is, and what frequency they are on, that they are members here as well. Now I am a bit more direct than most with crap like this, but I have done this very thing and vacated the frequency over it once I realized what I had done. But I would absolutely NOT change PL or anything on my gear if someone else came in and started interfering with my gear. In fact, if it was the 675 or 725 repeater and not the 600 repeater I currently have on the air which is a very busy linked repeater. I would switch the link over to that frequency so it was busier than before. ANd sort of force the issue. I am willing to work with anyone willing to work with me to resolve a problem like this. But these folks don't sound like they want to work with anyone and instead be jerks about it. So if they are gonna be jerks, my best advice is be a bigger jerk. Have nightly nets, make sure the frequency is in use as much as possible, BUt inform the other repeater owners that are also on that pair whats going on before doing all that. My guess is they will understand and appericate the effort.
  16. Mark, if you are serious about doing this and need assistance let me know. There are a number of things that are specific even to the way the codeplug has to be done in the radios that will need to be done correctly to get this working. MTR's are typically easier to program than the Quantar's. But I have done both. I will say this up front. You will need wireline cards in either of the stations to get it working right. There is no way around it. So doing an inventory of the stations to be used will need to be done to verify there are wireline cards in them and if not they will need to be located and installed. Quantars require some wildcard programming that is NOT documented anywhere. I looked. The only documentation I ever found used tone remote commands to control the PTT and my setup would not support that so I had to work out the programming to turn on the second audio input for the PL and some other things. Another thing to realize. While the RTCM can act as the interface for the linked system I don't know that it will do both at the same time and you MAY need to have another RTCM configured as a site on the simulcast that would act as the interface. For a voted channel bank system, I would use the console input and an RTCM or PI interface to bring in the system audio but that's a JPS voter configuration and I am gonna guess you will want to try to avoid the costs on that sort of setup. Let me know if you run into questions and I will try to help you the best I can.
  17. Well, first off, the JPS box. That WILL work, but it's expensive, and if you are looking at the RTCM, it will do the same thing for FAR less money. I would expect a single box would be 2 grand. And you would need one for every site. It's also only compatible with an SNV-12 voter that's gonna be a couple grand for the chassis and cards. So again LOTS of money. So a brief explanation of how simulcast actually works. And what the GPS is doing. The first function of the GPS is frequency reference. There is a 5/10Mhz output on the GPS unit that feeds that reference signal into the base station radios (they are NOT repeaters by their configuration in simulcast operation). This keeps the transmit frequency synced with all the other sites. Because we are dealing with FM, a difference of 100 Hz on the transmit frequency between two transmitters will generate a 100 Hz tone and harmonics of that tone in the receiver of the subscriber radios. Obviously if there is any variance in the frequency, you will hear that in real time as it happens. So rock stable frequencies are required. Second thing the GPS generates for all this to work is a 1PPS (1 pulse per second) signal that the channel bank, or audio control circuitry relies on to 'launch the audio at the same instant. I spoke about latency of the signal and how that could screw things up. Well here's how the 1PPS and the simulcast audio controllers deal with the latency issues. A system will have a 'PRIME' or MASTER site. That is when the audio comes out of the voting system and gets sent out to the other sites. Now those links can be direct to each site or a ring where the audio gets shipped along one after the other. So the MASTER site tags the audio traffic in a sense so that the far end and all the nodes in between know to 'hold' the audio (buffer it) Until all the sites have it and then release it at the same instant. In the days of TDM, there was also a 'jitter buffer' that kept things in the buffer to deal with the changes in latency of the connecting circuits. With IP and computers, it's done differently but the result is the same. The audio gets held up until the next pulse or the one after, before it's launched. Now there is also timing adjustments for overlap where more than two sites can be heard at the same time. Those adjustments are to deal with multi-site overlap and actually move the locations of contention, where the received audio is distorted. The timing adjustments MOVE the area's of contention that are unacceptable or very undesireable to other locations that are more acceptable for poor audio reception. Basically you move them into some corn field and you are done with it. Now of course you find those area's of contention two ways. First is through testing of the system during implementation and tuning. The second is wait on people to point out the area's of contention and move them then and hope the go the right direction as you tune the launch timing. I have designed, build, rebuild and added to a number of these systems. Mind you, the stuff I was dealing with was all analog FM both wide and narrow band and I was dealing with channel banks that were 20K each for handling the audio launch timing and shipping of the audio back to the voting system for the receive. This was all broadcast quality gear that would ship audio at FM broadcast bandwidths (100 Hz to 19Khz to haul the 19Khz Stereo pilot tone) not just 300 to 3000 Hz for two-way FM. I have NOT specifically worked with the RTCM units, but i do know how they HAVE to work in order for them to do simulcast. The last piece is the PL tone. That has to also be generated locally to the transmitter or not at all. If you can get away with it, don't run a transmit PL tone at all. It will make things easier in the long run. If you choose to run a PL, the base station can NOT be used to generate it. The Quantar and MTR base stations both have multiple audio inputs and one of them can be used to take in a PL tone and out it ion the air. With the systems I dealt with, This was handled with a Spectracom product that interfaced into the Spectracom GPS units and provided the PL. One of the other things you will need to be able to do is controlling the sites individually to interrupt the PTT signal from the RTCM or whatever you are using to key and ship the audio. The audio levels for each site have to be adjusted independently of each other. And that have to be spot on. The only way to do this is a receiver in a location that can hear all the sites. So placement of the MASTER site is important so you can monitor the TX audio and adjust it. THis has to be done with an O-Scope, an audio volt meter, or a TIMS set that measures down to the 10th of a dB. Three tenths is ALL you get before you start screwing up the audio. And you don't get that much with the PL tone because where the audio maximum deviation is 5Khz for wideband, the PL tone should never go above 700 Hz of deviation, and with narrowband that is reduced to 300 Hz. So that has to be SPOT on. Have a GOOD radio not a CCR to do this. And program it for flat audio out so you can hear the PL tone or it will be a mess.
  18. I would call the FCC and ask. If they say it's OK I would get them to put in in writing, but I don't know how they could keep you from using part 15 linking radios for the paths.
  19. OK, voting receive on a subscriber is NOT anything to do with multisite single frequency simulcast. Nothing to do with audio launch time, GPS or any of that stuff. What subscriber level voting receive is for, is a system that is broadcasting the same intelligence on multiple frequencies from multiple sites. Which of course it JUST like what we are doing with the linking. So the way it works is if you were in southern Indiana, you would program the radio to scan between all the LINKED repeaters in that area. The radio will then when receiving a signal from any channel in that scan group look at the signal level of the channel it's currently receiving and the other channels in that scan group and steer the radio to any channel with a better signal. I am not sure if it will also change the output frequency of the radio to that site, but I believe it will do that as well. Understand that since the system we are on has active display of where you are at. And is linked via the internet and latency in those links can vary greatly, you may experience audio jumps when changing from site to site as it's NOT a true simulcast system and the audio launch time is NOT synced. So be aware of that and don't setup your radio for receive voting scan and then wonder why you hear repeats and lost words as the radio bounces from site to site. Now, if you ARE looking to put up a true single frequency simulcast system with voting (about has to have RX voting). There are some options that are not killer expensive. I will say right out of the gate, NO INTERNET LINKING. The connected Internet doe NOT have the stability in latency even with a true IP based simulcast system. You will fight it, and it will ultimately beat you. The RTSM units CAN perform voting for the receive and handle the audio launch time stuff you need and I understand that someone did figure a way to get them to create synced PL generation which can cause you to rip out your hair trying to run PL generated from teh individual base stations. Second thing to know is this. What ever repeater you are going to use for one site needs to be used at ALL the sites. DO NOT mix repeaters. DO NOT mix repeater firmware either. The audio passing through the processing from the back connector to the air has delay. The firmware revision can and does change that delay in some repeaters. DO NOT attempt to run MTR3000 repeaters for analog simulcast. Motorola by their own admission has specifically created code in the firmware of those repeaters that VARY the audio delay time through the station. This was specifically done to force the purchase of GTR8000 repeaters that are 10 times the cost of an MTR when they were new. It would only make sense that the SLR5700 and SLR8000 have similar code in them as well. You will need a repeater that will natively accept a reference signal to sync the frequency output of the stations. So we are again back to MTR2000's and Quantars unless your pockets are REALLY deep and you can swing the 30K plus dollars for GTR8000 repeaters if you believe they need to be Motorola. I don't know about other manufactures gear. I work at a Motorola shop and that's what I am knowledgeable on.
  20. Steve, I would look into the ICS training online. That's where I got mine. Have 100 700 and 907 Got all of them online.
  21. Alright,,, damn. Make one little comment about ham radio membership not being what it once was and y'all are looking to burn me at the stake. So lets preface this. In 2024, 2 years away, I will be renewing my ham license for the second time. Which of course means in total I will have been a ham for 30 years at that point. And I have sat and watched the technical abilities of hams decline over the years. Now, do I think it will kill ham radio? No, I don't. And I will NOT be one of the asshats like those that sat around complaining about the dropping of Morse Code and how that would turn ham into CB radio, or that the decline in actual radio knowledge will do it in either. But in 30 years, I have met a bunch of hams, some of them are damn knowledgeable. But I am not seeing that as much any more. And I am not hearing serious technical discussions being had on the air. Of course, I don't hear much of anything other than on HF any more. And I am not seeing much interest in learning about radio in the ham community either. The move has been to DMR hotspots where the sum total of the RF communications begin and end in less than 20 feet. Using the Internet to bridge the distance. So as long as you can program a radio and configure a hotspot, you can communicate. For all of 20 feet. You realize you don't even NEED an antenna to talk that far. And yes, I do find all that disheartening. And what really gets me is all that demand for knowledge and wanting to learn is right here in GMRS and the service is limited to less than 1 Mhz of total frequency allocation and is ONLY wideband FM. We have no SSB, digital, packet, none of that. And we are fine with it. And I am good with it too. I just wish since there is so much interest in radio and how it all works here, that we have one little bit of one band to mess about with. Mind you, GMRS ain't ham radio. Never will be. I just wish that ham radio had the sort of participation that GMRS is now enjoying.
  22. Kinda laid that out that a growing number was that way. You are a retired PE. So gonna guess you have a pretty good education. And never bothered with the Gorden West books when you got your ham license.
  23. One of the other things that I haven't seen discussed here is the fact that government entities typically have a number of licensed LMR frequencies already that could be used. Part of those being Public Safety frequencies that they would have somewhat exclusive use of in their jurisdiction. So the jurisdiction would need to own and maintain a cache of radios for this purpose or require registered volunteers to acquire radios for the frequency band in use and get an MOU from the jurisdiction indicating they had permission to have that channel or channels programmed in their radios. And this can be anything from VHF or UHF single repeaters to trunked system radios. I personally have programmed system radios for a city we do work for that issue radios to established neighborhood watch groups. Point is, I am really not sure WHY a government entity would NEED a GMRS license as they have other resources available that are exclusive use.
  24. Because many years ago, when technology wasn't what it is now, Amateur radio was a vital part of communications when things went south. Having an Amateur Radio license indicated that you had worked hard and studied electronic theory, laws and regulations and were somewhat proficient in communicating with Morse Code. The real question is why are they STILL a thing. Because having a Ham license now means you bought a book with all the answers to the questions, read it for 3 hours and took a test so you could get on the air with your 30 dollar radio that makes all sorts of beeps and crap and irritate the guys that did it right back in the day. Just sayin.
  25. Yes, there are EXISTING licenses that are grandfathered, and can't be modified that we share the channels with. But he's asking about what I assume would be a new license, which I don't believe the FCC would grant. Now that's only based on the regulations as I personally understand them. But I am far from an attorney, or FCC licensing agent that would be making that final decision. It wouldn't hurt to have the entity contact the local FCC field office and ask if they wanted to get a license for community communications and EMCOMM use. They may well grant it. But they may not. The one difference in part 90 licenses and part 95 licenses is that a part 90 license holder DOES have some level of level of responsibility to the content transmitted on their licensed frequency. Not sure if that would carry over to a government entity having a GMRS repeater license or not. But if it did, that would certainly be a deal breaker for them if they were smart. We have little control over what others say on our repeaters. We can shut them off if there is an ongoing issue. But we aren't required to be mindful of anything said unless WE are the ones saying it.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.