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WRKC935

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Everything posted by WRKC935

  1. Kinda surprised that everyone is going on about aluminum as if it were less of a conductor to RF than steel. How many steel tube case antenna's have you ever seen, as opposed to the number of aluminum ones. Truth is that they use aluminum coated steel cable for high power transmitter antennas at HF and below. Most commercial base antenna's like the DB series are all aluminum construction. Aluminum conducts RF well. And reflects it well too, since most microwave dishes are spun aluminum. The trick will be getting a mount to connect to it with your specific application. But your idea of a mount that fastens to the body under the hood and comes out between it and the fender is a good plan.
  2. Rich is gonna need to comment on the configuration of the MyGMRS software. I don't believe that is a repeater controller though, only an interface to the network. That being said, you need somesort of connection between the two radios so that the RX from one will Key the others transmitter and pass the audio from one to the other for it to act as a repeater. This can be done via a repeater controller or a simple back to back cable that crosses the RX audio and COR from teh receiver to the TX audio input and PTT of the transmitter. It's fairly straight forward. Once that has been established the ID-o-Matic will need it's audio output connected to the TX audio input of the transmitter radio and the PTT of that radio. The Pi running the system interface software will need to be connected to the TX and RX audio and the PTT as well. You will want to pull the RX audio out of the receive radio via the flat / filtered RX audio pin and NOT the speaker output pin. This will give you a good level of signal to inject into the transmit radio that will not overdrive the transmitter. You will also want to set the receive radios programming to filtered audio out on that pin. Turn off all the compression and companding on BOTH radios. It makes the audio cleaner. The TX radio will need the input level set to 200mV. the choices are 80 and 200. The output of teh RX radio is always gonna be 200 at 80% deviation for whatever bandwidth you have the receiver set to. In the case for GMRS it needs to be narrow / 12.5Khz. The transmitter will also need to be set to narrow band. This is configured in the channel programming part of the codeplug. Set the RX radio for RX only on the channel and set all the tones to off. No need to trasnmit the powerup tone and the like over the air. When you were talking about the USB interfaces, I assume you were meaning the USB sound cards. You will need two, one for each Pi as they are doing different things on different Pi's. If there is a way to share them I don't know it and I wouldn't want to screw with attempting to do that level of configuration on the Pi's anyway just starting out with them.
  3. I'm sorry but NO... do NOT use adapters. Get the connectors that are correct for the application and don't adapt anything. Adapters are for testing things and NOT for permanent installations. I too would advise NOT using the LMR400. for 100 feet of run it's better to use 7/8 but the cost of that can be a bit much. 1/2 heliax would be better as well but another option is LMR 600 cable which has loss numbers similar to the 1/2 heliax, but at less cost. You will want to have your jumpers made up for your duplexer to the radios with good cable. The connectors on the GM300 radios are a mini-uhf. I would advise finding jumpers made from RG142 cable (double shielded) with the other connector matching whatever is on the duplexer. The runs between the duplexer and radios are important especially the receive cable. You want that to be as shielded as possible.
  4. This is NOT the way to be doing that. You need to find some 75 ohm cable and cut two EQUAL lengths of it and put the required connectors on it. Then you use a Tee connector fed with a 50 ohm cable. But the two 75 ohm cables have to be the same length. If you split the power in a divider, then only 50% of the total signal goes to each antenna. It will maintain the correct impedance, but cuts the power in half. When you run the two pieces of 75 ohm cable you correct the impedance mismatch that would be 25 ohms (2 50 ohm loads in parallel) by adding 25 ohms of impedance to each leg. And I would be looking for proper cable for this like RG11 with a copper shield and NOT TV cable. TV cable typically will not take solder as well and is a pain to terminate.
  5. Uhhh NO. This will not work for what you are trying to accomplish and in reality will do the exact opposite. If you have a cable that is low loss then more signal gets to the antenna to be radiated. A higher loss cable means LESS signal to teh antenna. It's true that a higher loss cable will SHOW less SWR (reflected power) on a watt meter, the mismatch still exists at the antenna and the reflected power is still there, it's just not making it back the cable to be shown on the meter you are testing with. In truth a high enough loss run of cable with a shorted end will show zero reflected power simply because none of it makes it back to the meter even though there is a 100% reflect or ALL the transmitted power. Now, all that being said. A 1.5 SWR is not that big of a deal and you are loosing so little overall power that even if that issue was corrected and you were at a 1 to 1 match, the performance of the radio and it's ability to transmit and receive would not have any noticeable change. Frankly your grasping at straws. The 2.38 match is concerning however. Not sure which Midland antenna that you are using, but I am wondering if it's a UHF antenna that is sold for ALL of the UHF band including ham and it's simply too long. I would advise you to look at the lower frequency channels and teh higher frequency channels. If the SMR on the lower frequency channels is lower than the higher frequency channels then the whip on the antenna is TOO long and needs trimmed. Consult the instructions on the antenna and see if it needs cut to a certain length for the frequency range you intend to operate it on.
  6. Not gonna get into manufacture bashing. I will tell you that quantars and MTR repeaters will at full rated output will act as a control channel on a trunked system. This means that they WILL transmit at full power for months at a time. I have PMed more than one of them that the log showed they had been keyed up for more than a year. I have never seen a Kenwood that would do that. Not saying they will not, just saying I have not ever seen it first hand. That being said, EVERYTHING pretty much has a place. I personally would NOT put a Kenwood repeater up on a tall tower on a busy channel, but I would have no issue with putting one in for a small system for a large family to use on GMRS. And I even see the applications of the two mobiles in a box. I sold and serviced countless XPR 8300 and 8400 repeaters and a number of Kenwoods that were pretty much two mobiles in a box as well. And in the right application they work well. But again, real world testing I have never seen the Kenwood that would hear like a Quantar,,, and the MTR3000 and 8400's will hear better than a Quantar from what i have seen in real world testing.
  7. Amiss how?? Not having coverage in down town Columbus from east of Johnstown? That's not gonna happen even though I overlook Columbus. Too many buildings and crap to penetrate that area. Try getting on top of a building and talking on it. Should work fine.
  8. Transmit and receive frequencies, PL/DPL tones that you are using and your call sign. Specify one minute less than the required interval for IDing on GMRS, this will keep you legal as a commercial repeater will NOT force ID and instead hold off until the channel is clear. IF you are planning on immediately connecting the repeater to some sort of controller then you will need to add the programming for that device. Consult the manufacture of the device for guidance on that. But no controller is needed for GMRS operation. Lastly, POWER LEVEL. You are only allowed 50 watts on GMRS and MTR repeaters were mostly 100 watt stations, you will need them to set the power level to 50 watts.
  9. Please understand,,, I have had a failure rate working on these of about 1 in 4. Most of it being the PROM not wanting to take programming correctly after being UV erased. Repairing them for someone that knows how isn't actually too bad. Would rather work on one of these as opposed to the new stuff where it's a few large IC's and very few supporting components. I will say that if you are a ham operator, it will program up for that as well. It may not broadband enough to run full power and have the receive at both ends (ham and GMRS) but I am thinking you might find a happy medium. And I only bring up the power and transmit bandwidth because a LOT of people forget that part. Can't tell you the number of high power Maratrac's, Spectras and even a few XTL's that had all the FRS and GMRS stuff in them and programmed for full power. And 3 dB is NOTHING (50 vs 100) as opposed to 500mw (legal limit on some FRS) and 110 watts (what the radio will do). But a Syntor that's working right is a really good stable radio. Have fun with it and good luck.
  10. Oh wow.. a 9000 Syntor. So there are questions that need to be answered here and you need to remember that is a 100 watt radio. GMRS is only 50 watts. Who ever does the programming on it needs to be aware of that so you are ??legal?? Not to mention that is NOT gonna be a narrowband radio. I keep hearing that GMRS is narrowband and is NOT narrowband. So, I would investigate that and verify that you are legal there too. Programming. If the unit has the display head (looks like a W9, but is NOT) it can be programmed with a RIB and cable. It IS most certainly a DOS only radio and is most certainly a SLOW computer ONLY programmable radio. When I say slow... we are talking 386/486 slow. IF you have a Pentium ANYTHING it's TOO fast. I been down that road. I do still have everything needed to do it including a computer that will go that slow. No, I have no interest in programming your radio, please don't ask. Those old radio's are finicky as hell, and it may or may NOT take a programming change at this point and I have no interest in telling you I broke your radio trying to program it. If it has the clam shell head (its' actually a Syntor and not a 9000) it will need programmed with a suitcase programmer or the EPROM will need erased and reflashed. Either method will work but it will depend on which radio it is on if it has a EEPROM and EPROM or a PROM. A double E will straight program, and EPROM will need erased with UV and can be programmed with a suitecase and the PROM has to be UV erased and flashed with a PROM programmer. Again, been through it, prom programmer is over on a shelf after the shop I work for decided they didn't want it any more. I couldn't see tossing it. As mentioned before.... there is a good bit of info over on BatLabs about those radios and you should be able to figure out WHAT you have there and proceed accordingly.
  11. Hmmm, 4dB huh? Yeah I suppose in a crappy duplexer. Really shouldn't be that much loss in any decent duplexer. Transmit combiner on the other hand can be more like 6 dB. Which is what I have. Of course I can connect 4 repeaters to that combiner and they can ALL transmit through it, and do. Instead of worrying about the loss in you duplexer, and not having 50 watts at the port going up to the antenna, worry about installing an effective antenna system with sufficient height to provide the coverage that you desire for your repeater. My setup is as follows. Receive antenna is at 220 foot at it's base, top of the tower. DB408 currently and will be upgraded to a DB420 this spring. Transmit antenna is at 110 feet. Antenna is a Station Master. It's side mounted and is shadowed to the South currently by the tower. This will be replaces and relocated by a split DB420 (two DB408 antenna's on a common mast) that the top antenna will be on the ham combiner and the bottom will be connected to the lower antenna. This will be relocated to the 180 foot level. Point is, as it stands, on a clear day the system talks 60 miles in some directions. And ONLY hears as well as it talks. Meaning I am NOT transmitting into area's that I don't have the ability to hear a 35 watt mobile. I will always have some level of shadowing from the tower, due to the fact it's 20 feet wide at the 180 level. But it's still able to talk a good distance in those area's that are not shadowed. There is some deeply rooted misconception that you need every last watt of power possible going to your antenna or your not able to talk. And it's simply not true. I have a commercial system over on the east side of Columbus that is 500 feet in the air. The transmitters are set down to 20 watts because they will not turn down further. It uses the same combiner I have with a 6 dB loss per port and 600 feet of feed line to the transmit antenna. It can still be heard in Springfield, but has NO ability to hear that far for various reasons. So it's talk out coverage is STILL with all that loss, far greater than it's ability to receive.
  12. So I spoke to one of my tower site owner friends and this is specifically what he had to say. I've been in the tower leasing business for nearly 30 years and my opinion is that it would be very difficult for someone to get into the tower leasing business today. I built 12 towers between 1994 and 2001 and all 12 ended up getting cellular tenants. 25 years ago it was possible to get some cooperation from the cellular companies regarding where they needed to improve coverage, today that is impossible unless you are running a 100 million dollar company with 5000 towers. Today, the cellular providers simply WILL NOT give you new site build locations or help you in any way. I know this to be true because I have been trying to get a dialog going with the cell companies for 20 years now. The cellular companies have sweetheart deals with about a dozen very large tower companies and give their new site builds only to them and nobody else. You could argue that a small startup tower company with less overhead could potentially build a new tower and potentially lease it to a cell company at a lower lease rate than what the big tower companies are charging but they simply do not care. So, if you go and build a 500' tower somewhere, or a 250' tower, or any other height without having a commitment from some type of tenant you are taking a huge risk. You might get lucky and have a tenant express interest in your new tower a year later, or 3 years later, or 10 years later. Or, you might end up with no tenants, ever. As was mentioned by others in this discussion, if you build a new tower in any area other than one that is extremely remote and undeveloped you will need to deal with local zoning regulations and permitting. Many jurisdictions now have tower removal requirements which means that, if you build a new tower and nobody uses it for 12 months or 18 months or some similar timeframe your conditional use permit which allowed you to build the tower will be revoked and you will be legally forced to dismantle your tower. If you have a lot of money burning a hole in your pocket my advice is to build new houses or apartment buildings, not towers. That is from a guy with actual experience in playing the game with vertical real estate. And while he is a guy ON the Internet.... he's NOT JUST some guy voicing his opinion without first hand experience. And neither am I. I am also a tower site 'co-owner' and manage the site. I have contacts in the communications field because I work in that field and have clients that are also tenants on various tower sites including the one I manage. I am not gonna tell you to NOT do this. I am gonna tell you that you REALLY need to think about what you are going to do, and be realistic. If the FAA has not granted you a build permit for a 500 foot tower, you are NOT going to get to go that high. I would consider refiling at a lower height and see if they allow it. But I wouldn't file any higher than 250 feet. I don't know where this site is with regard to an airport or a municipality that will have zoning requirements. You have a NUMBER of different regulatory entities that can shut you down with this whole thing and the possibility that even after the tower is up require you to remove it if you don't get tenants on it within a specified amount of time. There are ways around that, and if you get to that point let me know and I will share that info with you. But it costs MORE money in licensing and equipment that you will most likely NOT want to invest to keep the tower standing as it's all donation to the same government entities that are wanting you to REMOVE said tower but are done at a federal level that is out of their reach. And you need to consider this.. vertical real estate leasing is in some ways just like the leasing of buildings and homes. You will NEVER make money with only one site in the long term. You will have times that the site has no income or not enough income to be self sustaining. This is a tax write off to a point, but only to a point. Insurance, property taxes and the like can be written off. But other business expenses like electricity can't most of the time. Point is if you DON'T know what you are getting into, don't assume that if you build it they will come. Because they may not. And a tower site has a limited number of prospective clients to begin with unlike an apartment building where anyone looking for a roof over their head is a prospective tenant.
  13. That's actually part of the reason that broadcasters have tall towers. Yes, there CAN be a problem with RF exposure with a high power transmitter. That's why the radiation takes place high in the air so the exposure is limited. It's also why a typical tower site that is high power is very large with respect to the actual footprint of the tower. They will buy up large chunks of land to sit empty so that they don't have issue later with a housing development being parked next to their tower and the FCC showing up, doing exposure testing and requiring them to reduce power or raise their antenna's. There are exposure charts on the FCC site that will show whats legal for power level and antenna gain and height.
  14. Need to stick something else in here since someone else brought it up. DO NOT even THINK that amateur radio clubs or individuals are going to want to PAY ANYTHING to be on a tower. They get it in their head that they are somehow providing some critical public service by being hams that they are entitled to free tower space. Then when they get it you need to ride them like a rented mule to get them to clean up their installs to something resembling a commercial level install at your site. NOT requiring them to do so will get coax runs flopping in the wind, hap hazard line runs in the building and all other sort of crap that is NOT acceptable in a commercial communications facility. I am not saying that ALL hams are like this, but there are damn few that will do it right. And when you have a prospective commercial paying client doing a site walk through and the see it. They are typically NOT going to be coming to your site. Specific to what Steve said concerning the high gain antenna's on a short tower. It's not as much of an issue because the low gain antenna's near field will put them in to the pattern by if nothing else 'brute force' of the signal. This is why you can talk on a repeater that has a dummy load attached to it if you are in the building with it or are really close. And there are ways to deal with high gain antenna's on tall towers. It requires power dividers and low gain antenna's lower on the tower to cover the near field that is missing from the main antenna. Problem is it costs additional money that no one is typically willing to spend, at least at first. Then when the customer figures out that it will help their close in coverage, they approach the tower owner and he quotes additional cost due to it requiring additional vertical real estate (occupies tower space) and add's to the tower loading (weight and wind load). So they see an additional 3 to 5 hundred in monthly cost and they back away. Then at the end of the contract, instead of moving their antenna's down on the tower where it would be effective, they decide that the owner is screwing them and they leave the site all together. The tower owner has done NOTHING wrong, but the customer, not being familiar with vertical real estate practices, has decided that they are getting taken advantage of. Cell carrier's don't do this sort of stuff, because they know the game. BUT cell carriers are masters of the game. And THEY play it all the time, everywhere. They know what they are willing to pay and what they SHOULD pay, and there is no discussion on that number outside maybe 10%. And ONLY if they are really wanting on that site. One piece of advice that you might think on is this. There are pieces of equipment called transmit combiners and receive multi-couplers. These devices allow for a number of repeaters to be installed on a specific set of antenna's on a specific band. Meaning VHF, UHF or 800. The receive ones can be expanded to connect a large number of receivers in a band pass but the transmit ones are limited to maybe 8 transmitters per antenna. And this is for UHF. The VHF situation is much more difficult to deal with as the splits from TX to RX on VHF vary wildly and often overlap. But if you are marketing PORTS, you eliminate the need to install specific antenna's per customer, which reduces their cost. You limit your assigned vertical real estate that's occupied, and tower loading which means you have MORE space to rent. That reduced cost to the tenant is significant. A typical antenna install with line and tower crew is 5 to 10 thousand depending on how high, and the market you are in. This is how I am running 2 GMRS repeaters and have the ability to put 2 more on the air by simply programming the repeaters and connecting them up to the equipment. And I have a second combiner that will allow my to install 4 MORE repeaters on ham or commercial frequencies by tuning the combiner and connecting the repeaters to the combiner and receive multi-coupler.
  15. OK, sorry but I am gonna sit here and rip all this apart and make you question why you even CONSIDERED this idea. And at the end of it you will thank me. First off. What sort of business study did you do? Do you have prospective clients? Have you done an ASR search or even rented an 80 foot man lift jumped in it and went up to see how many towers are in the 2 mile radius of the proposed tower site? How many roof mounted antenna's are there (prospective customers)? If there are other towers in the area what sort of loading do they have? Or are they occupied at all? 300 vs 500 vs 190 or less Do you HAVE a signed contract for a commercial broadcaster? If not what the hell do you want with a 500 foot tower? NO ONE is going to want to go on the top of that stick that's NOT a commercial broadcaster. First issue is you can't hardly get a commercial two-way license with that sort of AGL antenna height. a Typical FB2 (fixed base / repeater) license is going to give the license holder a 20 or 30 km radius from the point of the transmitter site. Commercial radio is NOT like ham or GMRS where you talk as far as you are able legally. You can only operate inside your radius and you CAN get fined if you exceed that. The best way to limit that is to install a system that will self limit it's coverage by keeping the antenna below a certain height. Now this height will vary depending on topography, but unless you are in a 400 foot deep valley and have little interest in local coverage, parking antennas at 500 foot is pointless. 300 feet is getting back into a reasonable height and 180 is even better for MOST of the current radio technology that is going the small cell route for coverage. Low antenna's, low power and multiple sites. So 500 foot would be maybe 250 foot of usable height and another 250 of unoccupied steel that you are going to be paying for. Tower classification for lighting and height Tower's have lighting requirements based on height. The shorter the tower the less lighting it needs and the less upset people get (the FAA) when the lights are out. Towers to 350 feet are the first class. It then goes to 499. After 499 it frankly gets expensive and watched closely. And something as simple as a relamp can cost thousands of dollars to get a tower crew to do. Then you have to pay for a monitoring service at that classification as well. Not to mention that a single D1 strobe will cost 100 bucks a month in electric. A multihead high intensity system for a 500 foot tower is WAY more. You did say you have a SIGNED contract for a tenant right?? Dropping to 190 If you drop the height to 180 which would legally allow for an antenna that has a tip 18 feet above the mount point and a ground rod to extend above it, you have NO lighting requirements in most instances unless you are within a certain distance of an airport. And before you get it in your head that you need the height for talking distance. I have a GMRS repeater that on a good day will talk 60 miles from the transmitter site and the antenna is at 110 feet. This is in OHIO so it's not sitting on some 10000 foot elevation mountain top. The AMSL is 1350 at the ground. The tower is 240 foot total height to the tip of the lightning rod. I have dealt with repeaters with sky high antenna's. There is a 1092 foot tall tower in Columbus that has two UHF repeaters at 750 feet. The repeaters are up there to minimize line loss. They talk great.... in Dayton and Springfield. But NOT at all in Columbus because the near field coverage from the antenna's never reaches the ground. Gain is too high on the antenna's. So they will talk to the helicopter, but NOT a road vehicle. Something to consider with your 500 stick. The other thing with broadcast is power output, and wasted space on the tower. Any broadcast, be it radio or TV is gonna be high power, Meaning the commercial radio stuff will need to be several hundred feet BELOW the top of the stick where the broadcast antenna is. That offset is wasted space. Nothing can go there. So you either try to charge the tenant for the wasted vertical real estate or you eat the loss. Another things to consider. Better plan If you have property that will support a tower in a marketable area you need to approach the major players in the vertical real estate business and see if they are interested in installing a tower at YOUR location with them footing the bill for the construction. If there is market, they will be all over it... and that's what they do. If there is no market they will have no interest. That makes the math a lot simpler when trying to figure out if you want to lay out 250K on a tower build. And DO NOT forget a shelter, generator and the other added expenses of a tower in the total cost. Your quotes probably do NOT include that stuff.
  16. Answer to the specific question of who uses MURS. I do for sure. Or at least I put it in radios I have with the correct power out setting. MURS is nice because it's pretty lax on the license requirements (don't believe there are any) so you don't need any authorization or hold a specific license (like ham radio) to use the frequencies within the regulations set by the FCC. This is handy when you are doing site work with others and need radios that are cheap and simple enough to program (being a radio tech I have a supply of that). You just hand them out and collect them at the end of the day. A CP200 or other cheap radio that happens to fall from 200 feet off a tower is MUCH less of a loss than having one of your VHF / UHF XTS5000's make that same gravity fueled trip and die that horrible death.
  17. Larsen typically would print a model number on the bottom of their antenna's. Unscrew the NMO base from the mount and see if the number is there. Then look up the number and see what frequency band it is. Don't assume they they are right, seen the wrong antenna's used with a radio many times
  18. Yeah, what He said ^^^^^ Honestly, the 3dB increase is NOT going to do what you think it will. If you want to talk farther, raise your antenna. Mind you, my 40 watt (yep NOT even the maximum 50 watts allowed) MTR repeater running through a 4 port transmit combiner that has a 6dB loss per port will STILL talk 60 miles on certain occasions and has zero issue talking 40 miles anywhere the terrain is not blocking the signal. And with a 3dB increase you will need to get subscriber radios (mobiles and portables) that are DOUBLE the power output as well so they can talk that extra distance that you would get out of using 100 watts instead of 50 watts.
  19. Well, here is what COVID has taught us. Hams are typically older retired guys that have nothing else to do so they volunteer. Problem is with that is things like COVID are specifically more harmful to them and that's who's gonna show up. As mentioned before, young guys are NOT typically involved. Then you have the issue of ham radio operators being volunteers, and not paid employees. With a paid employee you have the employment to leverage them to show up and do a job. With a volunteer, that doesn't exist. And short of a quarantine or lock down situation, you have no method of holding that person in place and demanding their continued work. And even in the lockdown situation, you can hold them but demanding they work is not possible. Not to mention that they are only able to do so much. Operating radios and making coffee. So, pertaining to my comments and the league. Go look at their web site and the sites of the typical ARES groups. It's a sea of hi-viz vests and name tags with their call sign on it. Mind you I am tainted by ARES. The local group has been in the past a poster child for the way to do ARES WRONG. Demanding they be involved in public safety training exercises and other dumb stuff. So yeah, I don't see the need. And I do see EMA groups trying to move away from any reliance on ham radio for various reasons.
  20. Haven't said much in here for a bit, so here's an update. Finally getting the remote operator position going for the house so I can connect to and operate all the radios and repeaters at the site from home. While this don't sound like a big thing, it's 23 radios and repeaters as of now and will only increase. These range from GMRS and ham repeater and multichannel radios (control stations) to HF rigs that have assigned antenna's that are band specific and filters for those bands so they can co-exist and operate at the same time. I can also monitor things like the tower lights, generator and door alarms from the house. Which is handy.
  21. Uhh, yeah.... they told me that too almost 30 years ago when I got licensed. I realize that if you read the FCC rules pertaining to ham radio that's what it says. But the emcomm thing, and expermentation (most new hams aren't even qualified to operate appliances so I will NOT refer to them as appliance operators) is about done. Mind you I am also a commercial radio tech and have been for 13 years now. I keep seeing more and more government entities getting away from ANY reliance on ham radio operators and going other directions. And I am seeing this as they are actively looking for alternate methods, buying equipment to fill those needs and removing ham gear from their operations centers. Rather or not I agree with it, I am seeing it in my day to day as a commercial tech. Oh, and when you are at the ARRL booth at Hamvention... stay away from the Koolaid. Just saying
  22. Actually Anritsu sells a backpack for that monitor to carry it (way over priced Swiss bag with their logo sewn in it). Bag carrys the monitor and a medium sized laptop and the needed cables and bits. You are talking a 412 right? With regard to the dB discussion. I think we need to lay out that it's not as simple as I need more dB to talk farther or a loss of X dB is or isn't significant. As I mentioned before I have a system that the transmitters are turned down to 20 watts, because thats as low as they will go and they still talk farther than they hear from a separate antenna that is 30 feet above the transmit antenna. That system has a cable and combiner loss of something like 9 or 12 dB. But the 416 antenna at the top of the coax has 12 dB of gain so it's a wash. And the receive antenna goes into a tower top amplifier to eliminate the cable line loss to boot. Someone mentioned the noise floor which is a really good point. I can hear better from my tower at 240 feet than the 550 foot height (tower is 900) due to the noise floor being higher. And they are only 10 miles apart. Terrain has a TON to do with it as well. And this is where you get height gain. Now one needs to understand that a 6 Dbi gain antenna is going to have the SAME gain no matter the height. But what it's radiating through (whats between you and the tower) has a huge effect on the signal that gets to you. The rule of thumb is every time to double the height, it's like adding 6dB of signal level increase. Perspective on that is for every 3 dB of increase the power level doubles. So a 10 watt radio increased 3dB is no 20 watts. But dB math is logarithmic. so 6 dB is not 30 watts it's 40 watts. 10 doubles to 20 and 20 doubles to 40. So if you antenna is at 20 feet and you add 20 feet of tower it's like you went form 10 watts to 40 watts. Here's the part that is REALLY important. If you have a 40 watt signal coming out of a unity gain antenna. A portable radio may hear you very well, but that's doesn't mean it can be heard by your transmit antenna at 20 feet. Where if you are running 10 watts or even 2 watts, but are 40 feet up you will hear that portable radio and you can both communicate to each other. Of course cable loss comes into play when it's doubled in length, but using the correct cable for the height, meaning it has less loss than the perceived gain due to the height increase, you will get better performance out of the antenna system as a whole.
  23. Hobby radio is going by the wayside. It sucks, but it's still the truth. GMRS is not a lot different than ham in this respect. I realize it's not 'hobby radio' in the sense that ham is but it's not really commercial either. Commercial gets boosted as subscribers and reaccuring fee's keep many businesses away from going cellular but everyone else has gone to cell phones. And you can't blame them. The manufactures are marketing Android based radios now that will act as a phone in certain situations and they are making radios that work on the cellular network for those that really miss Nextel. All I can say is if you enjoy GMRS / Ham Radio or both, stay with it and don't worry about others not seeing a use for it. Phones work great until they don't. Radios will most likely work after the cell network is cold if something drastic happens, but don't let that be the only reason you are messing with radios. It really takes the fun out of it.
  24. Couple things with that. Mind you I don't know what your ground is like, but if you manage to get that stuck, getting it out would be very difficult due to shape and weight. Another things to consider is what it will do to your lawn if you are running it around. Steel tracks are NOT good on grass. You will cut up your yard just crossing it and turning will be worse. Not sure if that's a consideration, but it's worth mentioning. Another consideration is the lack of a PTO. Any attachment that is mechanized will need it's own power plant to work. So mower decks, tillers, snow blowers and the like will need independently powered. Personally I see this in the same manner I see a DR brush mower. It's great for the specific task it's designed for and NOTHING else. And I saw nothing in the video that an old Ford 8N with a bucket couldn't do just as well and be cheaper to own. Being in Alaska you are obviously aware that parts for ANYTHING can be a struggle. But I would really be concerned with what the drive system is on a unit like that and what the parts availability would be other than from the manufacture. And how many of them are even around to get parts from? Specific to the statements of buying a John Deer ANYTHING. Not if I won the Donald Trump lottery and had more money than the Catholic Church. But that is my personal opinion. But the reasons are there are equally good units for much less money and the right to repair thing as well. The skid steer thing has some merit, but will still tear up your yard. One of the positives to it is you can rent attachments for a skid steer from a local rental company in certain places and run them on your unit without the expense of owning them outright and spending thousands on some attachment you will use once every 5 years. So if it were me looking at it, I would be asking myself exactly WHAT do I want to do work wise, and how often will I reasonably need to be doing that sort of work. Take something like a tree chipper. If you have a property that you need to clear they are great. Cut everything down and chuck it in the chipper. Instant mulch. But once the work is done you get to use it again only after you let the land get overgrown again and need to cut down another bunch of small trees and bushes and run them through the unit. And it sits between uses, sometimes for years. I fell into this with a walk behind trencher. I bought it for WAY less than it's actual value ($150) and used it to cut in a trench between my barn and house for electrical line. I will use it to cut in a gas line from the street, cut in a couple trenches at my tower site to lay 4 inch conduit for HF antenna lines and then I will sell it because it will just sit and rust away after that. If you need it less than once a month, do you really need it at all?
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