WRKC935

Actually, one book, or set of books, that I would possibly recommend is the ARRL Handbook. Yes, there is FAR more information in that book than needed for a primer, but if someone with previous experience was to read through, all of the major parts of 'radio' would be there and you could figure out a list of chapters and pages to suggest to a new license holder to get them up and going. I would put the following chapters as must reads, in no specific order. SAFETY VHF/UHF antennas COAX Signal propagation in UHF FM radio 'technology' VHF/UHF equipment There is a LOT in the ARRL handbook. In fact, there is enough in the Handbook that my college electronics instructor used the ARRL Handbook as the textbook for the class. For those that aren't familiar, the book is probably the best compilation of electronics technology, communications theory and RF methodology in existence. It covers everything from the most basic explanation of AC and DC circuits, Ohms Law all the way to digital microprocessors. It covers RF techniques from 'DC to Daylight' starting with VLF at 136Khz clear through to Microwave technologies and wave guide design for 40Ghz. There is information on any and every sort of digital modulation method and of course AM/FM/SSB is covered in depth. Sure, it's WAY more than an entry level person would want to try to absorb all at once, but again, if someone were to put together a list of the specific materials to read, it then becomes a reference for furthering the persons knowledge going forward. This set of books and the ARRL Antenna Book are my goto reference for all things radio.

Gee, couldn't get anywhere finding someone dumb enough to petition the FCC for DMR or some other digital modulation format on GMRS , so you decide to bring up the question of the actual existence of the FCC. DO you actually work for a living or are you stuck in your house, just sitting there figuring out new ways to post stuff on the web to wind up the masses and cause trouble? I said this before, if YOU don't like the service, find a different one. Or go entertain yourself with freeband, pirating on commercial frequencies, or just put Zello on your cell phone and use that. It's become clear that you are not here to have a reasonable conversation about any topic that resembles reality and instead just post things that will stir up the best result. Welcome to the ignore list. You have joined a rare bunch that up to now only included OffroaderX. May the two of you find happiness in limbo.

Still didn't answer the question about why YOU don't bother to go petition the FCC about making a rule change allowing DMR on GMRS. And again, as myself and others have said in this thread. This is a dead horse being beaten again. This has been rehashed over and over again. No one is going to petition the FCC for the rule change, including members here who have actually successfully petitioned the FCC for rule changes. And the reason is simple. DMR on GMRS will cause nothing but problems for the current users. It's about as dumb as when the FCC decided to change CB radio from 23 channels to 40 channels making everyone's equipment obsolete when the change took effect. The actual part 95 radios that are in service will be unable to operate with DMR. Same issue exists for adding channels to GMRS or making GMRS narrow band. If you want to petition the FCC for a rule change, and get it to the point that it's open for public comment, we will certainly comment on the change. Until then, be happy with what you have, and if it doesn't suit your purposes use a different service. Because while your numbers are correct, they apply to DMR being effected by Analog signals. Not the effects of DMR on the ANALOG signals of the multitude of users out there currently using the service within the rules as they are now.

There is an 8 page discussion on this topic elsewhere on the board. It's the same dead horse with a different bridal. Here's a thought. Why don't YOU petition the FCC for a rule change allowing digital modulation on GMRS? And I have NO idea where you got the idea that DMR is somehow better suited to deal with analog signals than other analog signals. Any type of signal getting into a DMR receiver will raise the BER and cause artifacting and digitization of the audio. That's if it comes through at all. Public Safety is discouraged by the FCC from using any sort of DMR because of the issues with it not playing well with analog signals and the fact that the public safety frequencies were issued multiple times in an area, sometimes within the same county and the end users would just run different PL's to filter out the other users traffic. There is a requirement under part 90 that a user much first monitor the frequency in use to be sure that there isn't another user on it. That is what the MONITOR button is for, and why there is a 'Hub defeat's PL' that turns off the PL requirement on a mobile radio when you take the mike from the hanger. Now I don't believe that GMRS has such a requirement. It's also why there is a channel free and color code free setting in DMR radios. When using a DMR programmed channel it's suppose to be set for channel free if there is another user close enough that their licensed coverage area overlaps your coverage area. GMRS doesn't have 'licensed coverage area's. We are power limited but that's it, as long as your transmitter is 50 watt's or less, the sky's the limit on antenna height and antenna gain. Yes, if your tower is over 200 feet you have to have it registered and have obstruction lighting, but that's not a height limit, it's an additional requirement by the FAA not the FCC for towers exceeding a certain height. You ant DMR, go get a part 90 license, go get a ham license. DMR is prevalent in both of those services. It's not allowed on GMRS currently and I really don't see that ever changing.

Well, you need to explain 'other networks' Are you talking about networks other than the one associated with this site or are you referring to regional groups within this site / system? With the configuration of the software for connectivity to a specific system, only that system can be accessed with a specific configuration. The system (AllStarLink) that is used for linking requires the configuration to point to a specific set of servers that are for the system. User names, passwords, node numbers and other related stuff only has one entry. So connecting to 'multiple systems' while it MAY be possible, is not a supported configuration with this system that I am aware of. Explain what you are wanting to do, what specific issue you are having and you will be assisted if it's for THIS system. For configuration information to other systems, and you need to define 'systems'. We define systems as a group of NODES (individual repeaters) that are connected together either directly or via a State level HUB or possibly to one of the regional HUBS that are part of the overall system. Are you defining a system as a single or possibly a single group of repeaters, such as the MidWest group, or are you referring to a system level difference such as MYGMRS.com or USGMRS which is a different SYSTEM?

Yeah, If you take your mouse and hover over his name a box will pop up. Bottom right is a button 'ignore'. Just click that as many others have. It's a pretty common practice. He seems to be the self appointed court jester or something. It seems he likes to keep his post count higher than anyone else around here by nitpicking every little thing he can find. Other than that, he's a legend in his own mind with all things GMRS and even has a YouTube Channel to pass on his wicked smartness about hobby radio. Oh, and for some reason no one understands, and by his own admission, he is NOT a river in Italy that Romans can freely cross. Never really understood that one. But he openly states that in his YouTube persona. Welcome to the board.

Is there something else going on here?? Read the copied part of the post again. G R M S ???? really thought it was GMRS but the copied stuff keeps referring to it as GRMS. Not that you can link a part 90 freq to part 97 or any other service, but it just strikes me as odd that the incorrect(?) GRMS moniker shows up multiple times. As if the guy is trying to setup his own radio service.

That is a HUGE decision if you are going to any significant height. And the biggest issue is cost. Putting up a tower over 100 feet can easily exceed $50K in cost. And that could double depending on property value. Any sort of 'group effort' tower should be placed on a neutral site, and not at any one members location. Reason for this is simple. Legally it's THEIR tower. No matter how hard you lawyer that effort, it's on their property and locks it into them. And there is the need to figure out income if a tower of any significance is erected and a prospective tenant approaches the group / land owner for access. The land owner WILL want in on the income stream if a tower on his land is all of a sudden making 2 grand or more a month. And yes, depending on location and other factors is a reasonable number. BUT, do not expect a tenant on your tower as a method to pay for it. Another requirement is cost going forward. Tower sites have maintenance costs, taxes, utility costs and anything else a piece of real estate would have. And additional costs like obstruction lighting maintenance and registration that no other piece of real estate has. But, renting space from one of the large vertical real estate companies has it's own set of issues. Mainly that you would be hard pressed to get into an agreement of less than 5 years with them. And their contracts are iron clad. If you enter a contract with them, it doesn't matter if you are there 5 months, or 5 years. You are going to be on the hook for the 5 year term of the contract. The only plus to renting is you do have some way out at the point of the term of the contract ending. Keep in mind that this is hobby radio. Folks loose interest and ultimately there may come a time that no one is interested any more. With a rented space, you can hire a tower climber to remove your antenna's and such from a rented site and not extend the lease for another term. With an owned site, it is real property and would need to be transferred to another or razed (tower and building torn down) and the property sold. Which again, creates issues with the original group that funded the build. The way that the ownership was worked out will have repercussions on how the money from the sale of the real estate gets distributed. And those things need to be worked out prior to building a tower site that will be for a group. I understand this rat hole pretty well and can give you information on what needs to be done and how to do it, within reason.

I got mine in Dayton as well. Charger, used battery, antenna and the radio for $420. One of the guys with the local group had a couple of them and a couple different mission plans to stick in it. I found the Bluetooth programming function to be great as I don't yet have a programming cable. I also need to track down a KVL adapter as some of my personal radio stuff is encrypted. I did have one issue with dropping a mission plan in it that wasn't right. Radio wouldn't boot correctly. The three finger salute reset the radio and restoration of a known good mission plan got the radio running again. Being a Motorola guy, I was on the hunt for an APX for seemingly no good reason other than the desire to own one. I ended up with a 7000 that was VHF/ UHF-R1. Which is the most desirable option to get for frequency bands. I was never a big supporter of NAS on a carried radio and I have a legit system ID and radio for work (radio service tech) with direct access to a full system key so I can build any codeplug I want for 'scanning' and when ask what I am doing with a system radio I have a reason to have it. I mess with the Harris a bit, but I have found the accessories are stupid expensive. And taking into account I have access to second hand accessories at the office, it's sort of a no brainer to prefer the APX. I have one RSM for the Harris. I have at least a dozen RSM's including the 'commander' type with display and channel knob for the APX. Have the green XE RSM's, have a Pelitor headset and interface for the APX that is noise canceling. The noise canceling feature on the Pelitor is good enough I can have a phone conversation on the Bluetooth model I have connected to my phone from the gun range I am a member of while I am shooting. Of course batteries are not at all an issue as I go through the recycle bin and get out of date batteries. Some that have only been charged a few times and are fine, but out of date. Fire service doen't use out of date batteries. This is due to the safety rating for the batteries while in combustible environments and in fires. My radios are not used in life and death situations on a regular basis, so I am not effected by these things. I will say that the 'mission plan' design with the ability for the radio to have multiple 'code plugs' that are user accessible is a really handy feature for building travel configurations when you are out of area but not needing to have endless radio zones in a codeplug. Sure you can have multiple codeplugs saved in a laptop for the APX and program the radio as needed with them. But being able to store them in the radio, and switch them on the fly is much handier in my opinion. I will also say the programming software is a bit hard to navigate if you are accustom to other programming software. And in truth it's just a pain all around. But once you figure it out, it does it's job. Congrats on getting the radio, welcome to the Harris owners family and if you really like it a lot, there is a mobile version called the XG-100M. Basically the same radio in a mobile configuration with some added features. Might be something to look into.

FAA went nuts on any drone over .55 pounds. So basically anything past the little Walmart drones requires registration. Fines are crazy if you get caught unregistered. I don't know what happened that brought all this about, but they all but killed that hobby, and basically anything related to RC model flying.

And this is the reason the HAM radio repeaters are quiet. GMRS has in a way turned into HAM radio, going beyond what it was intended for. The original intent was for situations that you needed communications, but didn't want to go the full route of a commercial license on Itinerant frequencies or MURS. GMRS is a nationwide license (commercial frequencies outside SOME itinerant licenses are NOT nationwide) you can use with family, and other license holders. We of course have transitioned beyond that to rag chew when it's not being used for the original intent. Repeater linking is a lot of what makes that possible. I have 3 repeaters on the tower. One is the tower owners (725). It is open but all users are requested to use my unlinked repeater (675) for local comms unless the repeater is busy. Then there is the 600 that is linked. It gets a bunch of traffic. Some of it is local traffic for the link but much of it is from other repeaters on the system. The 675 see's maybe 3 hours of use a week and the 725 see's less than that. So area of coverage has a lot to do with how busy a repeater system will be. Stand alone repeaters in medium to low population densities are not going to have much traffic outside the system owners. Large multistate systems that cover multiple high density population centers (Chicago, Indy, Columbus, Milwaukee, and most of the state of Indiana and Illinois) will obviously be busy because there are more people in the coverage area so you have a higher possibility of people being licensed in the coverage area. You mentioned pre-arranged comm's. That's a NET in ham radio. And we do see traffic during nets on ham. But very little normal conversation. And in truth, everyone has a cell phone. Your wife, the kids, the neighbor down the street. So when you tell Jr to take a portable radio you get met with "Dad, I have a phone, I don't NEED this stupid thing" or better yet, try putting an antenna on the wives car. "That ugly shit is NOT going on MY car." Figure out how to get past that and you are getting somewhere. Otherwise, be happy that you have a hobby that you enjoy and hope it doesn't go away in your lifetime.

I just realized that the repeaters on the map site don't actually show the call sign of the repeater. I went looking for a repeater I am hearing from the tower but there is no way to search by call sign or even review by call sign looking at each repeater in Ohio. I was sort of surprised by this.

Oh I know about not being active any more with HAM. I was very active until I got a job doing commercial radio and it seemed I had all these ham friends that I had never met come out of the woodwork wanting to know about old equipment and what was done with it. Wanting me to look at their broken radios (for free) and all sorts of other stuff. Then I ran into the issues of offering to assist with building and maintaining infrastructure (ham repeater) and being told they were different and what I knew about commercial radio didn't apply to ham repeaters (while they were using Motorola repeaters that I serviced daily). That pushed me away from the service for a long time. I am slowly getting back to it and doing my own thing. The problem it created, is I now ONLY do my own thing. I help some folks, but those groups I had issue with are shut out. I refuse to do anything for them. The one group I even offered tower space and a backup repeater to. Completely free, their call sign and all on the machine and would only require a phone call to get it activated if their stuff failed. They balked about it, Said they would need access 24/7 to the site. ( There are two people having access like that, me and the site owner) when I said they would need to schedule, but their access was not needed as I would host it on my gear as a backup and they didn't need keys to the site they again balked and said no. So the tower their repeater is on will be coming down soon. They have no where to put their repeaters and have zero options to stay on the air once the tower is down. I see it as being NOT MY PROBLEM.

Yeah, there is this as well. And even if some GMRS Karen were to call the FCC, if you are on a shared GMRS / FRS frequency, and actually got a response from the call with the FCC inquiring what happened. You just tell them that the minor's all had FRS radios. At that point the situation goes away. I don't believe there is any age limitation on FRS since it's a FAMILY RADIO SERVICE by name. ANd of course no license is available. We as GMRS users can communicate with FRS users so you are good on all levels. And what radios the kids are actually carrying isn't going to be known by the FCC since they aren't going to be tracking through the woods looking for kids carrying APX8000 radios, I am thinking you are pretty safe. Truth is as you sit and look at it, the FCC sort of screwed up with putting FRS and GMRS on the same frequencies with regards to ID enforcement. If you are on a GMRS repeater, then it's pretty cut and dried. You are operating within the capacity of your GMRS license. Outside of that. Since there is no specific text in the regulations that state once you have a license that you are always operating within the scope of that license. That would apply as long as you were not operating any sort of base station at a higher power with an external antenna. FRS radios of course have no ability to have an external antenna, so be mindful of that. So the way the regulations read. If you are in possession of FRS radios and GMRS radios, no one has any idea what radio you were using when you were talking unless directly observed. So what did you use? Only for you to know and there are other laws on the books that apply to requirements of self incrimination. So there is that too. Further, and yeah, I am splitting hairs, but I don't know if there is a requirement for a specific radio to ID or if there is just a general requirement for an ID when it comes to family use. Meaning, can YOU ID for both stations during a conversation so that it's aired? I don't know, but it's completely possible, you would need to ask the FCC for clarification.

I agree with the expensive statement if he were to use off the shelf SCADA gear. It's not even cheap on ebay used. But, since you know the stuff well, you know that it's data packets that are almost spreadsheet simple. It's a 'sensor X value Y' sort of thing. And could be easily written into a combination Raspberry Pi / Arduino setup with both digital and analog I/O being monitored by the Arduino and fed to the Raspberry Pi via serial or USB then converted to the data packets via a conversion app and broadcast. The Pi could then also be programmed to receive packets off air and react to certain values or I/O inputs from the remotes. Including launching status messages via MDC. I did something sort of similar once with a CDM radio and some base logic. A CDM can be commanded to change channels via the rear accessory pins. It's 4 input pins and can select 16 channels. If you build a logic output to control those pins. Programming the radio channels to send individual MDC1200 status packets for each channel then changing the channels and keying the radio it lets you send 16 different messages. The commercial LMR license wouldn't be a requirement on this either. GMRS allows for some basic 'digital' signalling on the service. I don't know how much SCADA type data he would need to be moving around. But if he's writing the software to do this, it would be easier to use a known working solution and copy that instead of reinventing the wheel by writing his own system from scratch.

Went back and read the original post again. What you are also talking about beyond alerting is SCADA (google this) SCADA is a common radio system that is used in utility and industrial systems for monitoring and control of water, sewer, electric and a host of other applications. It's a bi-directional system that uses short data bursts to pass control information and data to and from remote sites and operates on established standards. It could be implemented along side the alerting that was discussed before with the correct squelch setting in a radio so that the datagrams were NOT audible in the subscriber radio unless the alert tones were sent opening the radio up. There are adjustments for the delay and duration of the datagrams being sent so it wasn't constantly busying the channel up with packets. This would certainly require your own repeater and the rules pertaining to using it on GMRS might need to be researched to verify it is legal. But if you are wanting to go this route, spending the money on your own LMR frequency (commercial frequency) wouldn't be a bad idea.

If the application is to do alerting to the radio, there are a couple methods to doing this that are straight forward and commonly used in public safety communications. First being Quick Call 2 in Motorola speak or two tone alerting. This is a method that two tones are transmitted over the air that the radios are pecifically looking for and can be programmed to react to. Think old school fire paging. Low tone, high tone, tweedle tweedle tweedle, and then some voice announcement. The radio when programmed correctly for this sort of alerting can remain silent until the tone group is received or be actively monitoring a channel and alert to the incoming message. The voice announcement would be computer generated, either through a text to speech engine where the alert notification is stripped of the pertinent information and run through the speech engine or conversely could be canned messages, pre-recorded WAV or MP3 files that are played over the air. Their selection of the message would be a function of the alerting engine. Issues with this are simple. The frequency of the tones are specific. They must be generated within about 2 Hz of the programmed values in the radios. And QCII tones are delineated to the tenth (0.X) of a hertz. So accuracy is a must. Interfaces can be constructed with a simple CM108 based sound card that will handle the audio generation and PTT function as well. Search CM108 All Star interface for more information. DTMF codes are also a possibility but may cause issues on repeaters that are owned by others since DTMF signalling can be used for repeater controller function changes over the air. If your DTMF tones turn off their repeater, they may well ban you from their machine all together. But Motorola and other commercial two way radios that are typically used for public safety will also recognize this type of alerting. MDC1200. MDC1200 is of course used for radio unit IDing, but it can also be used for Status messaging. The status programming in all radios that are receiving the messages must all match. Then once you have the status messages figured out you put them in radios that have displays. The display on the radio will show the preprogrammed text message on the screen. This method does NOT send texts. It has a set of 10 or so status messages that are set by the 10 or so MDC1200 data packets. You would need to program your software application to create those MDC1200 datagrams and feed them into the radio for transmission. Remember that you HAVE to identify your transmissions. So in addition to any voice or datagram announcement you have to have the transmitter ID. This can be done via a recording being played, a speech engine or Morse Code at 20 WPM. And remember that if toy are doing this across someone else's repeater, you need to get their permission. Don't simply do it and expect them to be happy with it. I have a local repeater that mirrors the coverage of my linked repeater. It's for local traffic only and I PERSONALLY wouldn't take issue with this on my machine, but if you're not in the Central Ohio area on my repeater, you need to seek out the owner of your local repeater and get their blessing. Moreover, I would offer them the programming information if they would like it so they can set their equipment to receive the alerts as well. Any of this is going to require radios that support the signalling methods talked about here. Your cheap import radios and standard part95 stuff will not work with any of this other than the straight voice announcement. Bear that in mind. CDM1250 and CDM1500 mobiles support these functions. THe 1250 and 1550 HT series portables do are well. The XPR series that are FULL DISPLAY support these functions will also work. If you want to spend more money the XTL radios do this as well.

Thought on this some more. Couple more considerations with regards to the battery chargers. A 48 volt plant is actually -48 volt supply. Meaning the positive side of the end of the battery string is connected to the ground or 'return' in battery plant speak. So again, if the output of the battery charger / power supply HAS to be isolated. So again, you need to be aware of what you are doing and what you are working with if you are going to mess with this. But again, 48 volt battery plants have serious current producing abilities and doing something incorrectly when it comes to this level of energy can have disastrous results.

Oh, BTW. If you decide to try independant supplies. You need to verify that the ground is ISOLATED. Meaning the battery side output is NOT connected tot he ground pin on he power cord. If it's connected on two or more of the chargers, the 12 volt power in the batteries will back flow from the adjacent battery back through the power cord, into the building ground and then into the ground of a battery effectively creating a dead short. With a set of even partly charged batteries, you will cause a fire at that point and things will get out of hand quickly.

So here's the issue with using "battery chargers" referring to the normally available 12 volt car battery chargers that would be readily available. They are non-regulated and non-filtered. Due to that the an AC hum would be superimposed on the DC power and would show up it the audio signals of the radios. Proper way's. First is a site generator. Most current 48 volt rectifier systems are modular. Meaning they are not one huge DC supply but a number of independent supplied in parallel that charge the batteries and power the connected equipment. So a full failure of that equipment is very rare as opposed to a utility power fail that renders them inoperable due to no input power. Any properly constructed cell or communications site will have in place a manner to connect a large generator that will run the site during a grid down event. A medium sized (30 to 60KW) tow behind generator and the correct cable would be the correct way to run the site. ANd you are going to need something larger to run a bunch of 200 amp battery chargers anyway if you tried to do it the way shown here. Second way is a purpose built 48 volt generator. The phone company has had these for years. They look like a standard large portable generator with an 18 to 20 HP motor but the output is 48 volts and not 120 / 240 volts. They are built specifically to power a 48 volt battery plant during maintenance or replacement of a 48 volt battery plant rectifier. Something of this nature could be constructed with rewiring a couple alternators with external regulators and running them in parallel to produce the required current level needed for such a thing. Contact your local telephone company or industrial generator dealer for more information. Lastly, and the way to NOT do it unless the chips were down and there was no other way. Similar to the manner that was shown but with switching power supplies of a current rating that meet's or exceeds the load at the site, but with a clean output and not a bunch of noisy battery chargers. Still need a generator if the grid is down. But a better way is find a proper 48 volt rectifier and a generator, put it all in an enclosed trailer and drive the whole thing out to the site. Remember that you are going to need wire to get to the power distribution breakers to feed the system. SO if you are serious about doing all this, you need to prepare ahead of time and not think that you are just going to wing it during an actual event.

Anyone built a solar powered repeater. I might have access to a site that doesn't have any power currently. I would have roof access to install a couple solar panels and run a repeater. Repeater would most likely be a 25 watt XPR8400 that would not be linked for the time being. Thinking that two 100 ish watt solar panels with a battery system should be enough but would defer to others that have done this and been successful with their efforts.

OK, FPP and the XTS5K. First thing is defining what you want to do with it. And how you want it to lay out. You can 'assign' some number of zones in the radio that are FPP and others that are non-FPP that you would program with a computer. The first thing to know is don't screw with the personalities assigned to the FPP channels. Each FPP channel has a specific personality assigned to it. If you mess with those, the channel will no longer function with FPP. So figure out how you want the radio laid out. FPP is cool and all to add channels on the fly, but 15 zones of it is a bit much. You can program the radio with standard software with FPP. But as mentioned there are restrictions to having FPP in the radio. The biggest being EVERYTHING in the radio has to be conventional.

If I run dual ISP connections with fail over, will the servers see my node change IP addresses and update the working public IP address of the node? If it does, how long does that take to happen?

Well, the truth is the antenna system more than ANYTHING else. You can have the most expensive repeater on the planet with an antenna at 50 feet and I can out distance you with a couple garage sale M120 radius radio's and a repeater link cable and an antenna that's 400 feet in the air. And you have to understand there are three measurements of height when it comes to all this out. First measurement is AGL. That means Above Ground level. If the antenna is on a 300 foot tower but mounted at 200 feet the antenna is 200 feet AGL. Then there is AMSL or Above Mean Sea Level. That is the height at the ground where the tower is above sea level PLUS the AGL level of the antenna. Then the most important one that is really important. That one is HAAT. Height Above Average Terrain. Now this one you are not going to measure with a tape measure. It's a multipoint averaging calculation. To figure this out, you create a circle around a tower out to some distance. I believe the FCC uses 20 miles but it could be more. Then you draw circles within that circle, typically 5 that are equally spaced. Then you draw a cross and an X through the circles to create the points of reference. The lines can vary from every 22.5 degrees to every 5 degrees depending on the type of calculation you want to do. You then get a topographical map of the area in the circle and document the ground level heights at every one of the intersecting points on the map. Add all those together, divide by the number of readings and then subtract the number from your AMSL. That will give you HAAT. The FCC website will do this for you, so don't think you need to do it manually. This is why an antenna on a 500 foot tower that sit's in a 1500 foot deep valley can be out talked by an antenna on a 10 foot mast pipe on any top ridge of the peaks above that valley. Sure the 500 foot antenna will talk gangbusters in that valley, but not at all outside it. And the 10 foot one will talk then entire valley plus down into all the neighboring valleys. We have one repeater on the MidWest system (Crete600) that talks 120 miles across it's coverage area. I have personally verified this by starting in Chicago and driving over half way to Indy before I fell out of the coverage area of that repeater. And it all has to do with the height of the antenna. Interesting EXTREME example of this. Ham radio has satellites that are repeaters. The repeaters are limited at 2 to 4 watts. They are 200 plus miles above the earth and you can hear them on a portable radio (HT) with a meager beam antenna. And you can also talk on them with the same portable radio and beam antenna.

Yeah, looks right to me as well. I would have used a different antenna line (LDF4-50 hardline) but I have thousands of feet of it on hand and connectors for it so it's not just cheaper for me (I don't have nearly that much LMR400) it's actually free for the most part. If you happen to have a dummy load that you could connect to the duplexer in place of the antenna I would be interested to see what your power readings were with a dummy load on the antenna port on the duplexer.