JohnE

https://www.blm.gov/sites/blm.gov/files/Lands_ROW_Motorola_R56_2005_manual.pdf

always, always cut them longer. you can tune w/set screw as there is ~1/2" of play in there. the big M's spectrum antennas were hard to get right the first time and had no real BW AS(now PCTel) mosaic antennas have a lot of leeway to tune and is my preferred gain antenna

the truth of the matter is "most" base antennas will have a "range" that they are good for (i.e. 460Mc to 470c) there is little or in most cases no tuning required. as to mobile antennas that is a bit different. Unity(0 gain 6" whip) antennas do not need tuning. The 3dB and 5dB will have to be "cut" depending on brand but there are a few that will be good to go out of the box. I also agree w/WRAK968's suggestion. I don't know what meter you are using but a 2:1 swr is 10% of forward power and 1.5:1 would be 4% of forward power. 100 forward 10 reflected would be a 2:1 100 4 1.5:1 as an example

9/11

ran into that problem. found a way around it though.

what is it going to take to clear the trees. also what are the local rules on antenna height. some places have restrictions on height and fall zones.

just a wee bit

in the grand scheme of things it's pretty negligible N connectors are typically 0.15 loss @10Gc, now dumb that down to 400Mc and it's irrelevant.

I have not seen it work in 7 or 10

you can always shell out 5k(on the low side) for a commercial machine on a licensed pair and add the monthly for the site to that. all you have to worry about now is the co-channel. just sayin' JE

put in wrong post

forgot about doing this too use Google earth find your location and the 2nd location tools, ruler . make and save the profile close the ruler right click the saved profile and look at the elevation profile that should give you a better idea "if"it will work. now to add to that I can talk to a machine that is ~40mi away from me. my elevation is ~1215 the machine is ~1350 on a 60' water tank. w/3 "hills in my way at 1 mile out is 40' 10 miles out 230' 25 miles out 315'

some more info would be helpful how far away is sons location, same for the ridge/hill in question as well as direction.

so you have a 408 and a 404 or are they a 411 and a 420. 404 https://www.commscope.com/globalassets/digizuite/262254-p360-db404-b-external.pdf?r=1 408 https://www.commscope.com/globalassets/digizuite/262257-p360-db408-b-external.pdf?r=1 411 https://www.commscope.com/globalassets/digizuite/262260-p360-db411-b-external.pdf?r=1 420 https://www.commscope.com/globalassets/digizuite/262263-p360-db420-b-external.pdf?r=1

not so much they come from the factory turned all the way up. most of the time they don't even need to be half way. as a side note the new trbo radios have gain settings in the programing software that can complicate things a bit too. just n FYI I do prefer the way Kenwood does it.

the Kmc 27 and 35 are meant to be held close. if you back off from them the audio drops off very quickly. the base mic has a rough working distance of 12"-18" and is not adjustable like big M.

at 50' 400 would be good 100' 1/2 super or hard line in excess of 150' 7/8 after that you get into the really big stuff 1-5/8, 2-1/4 and waveguide.

just a note to the 400 cable vs LDF these are completely different types of cable to deal w// 400 is a nice flexible fairly user friendly cable. LDF4 on the other hand for a novice is not going to end well. it is fairly rigid bend it too much and its done, have seen that 100x over. putting on the connectors is pretty strait forward depending on what you buy. you will need to have some practice to get a feel for it. wouldn't even bother w/LDF5 that is a 7/8 cable that requires specialized tool to put connectors on. as to your height, 2 story cape style house in the end should give you 30' of height to tip, roughly. look at this as I have finally added new pics https://forums.mygmrs.com/topic/252-cable-types-and-losses/

guy at it at the top and half way down

simple and effective

look at this forget the RICK basically works w/most 16 pin M radios http://domtoren.com/990/Bi-_or_Uni-directional_Repeater_cable_for_CDM_type_radios.pdf

forgot to ask about your antenna system what are you running? cable type/length and antenna

the 880H would be a waste IMO as it is 40W capable. If you're going to run at 10W just get an 880 that runs at 20W. as to the quality of the audio that would be subjective. I can't speak to the Btech but I am a long time Kenwood guy and happen to like the audio quality and features of the Kenwood 5W vs 15W has to do w/what you need to overcome the noise floor and have a clean signal into the machine. on a side note the Kenwood software is very intuitive and simple to use. JE

ERP 388W 1 /58 346W 7/8 and 400 for the fat 2 1/4 based on 50W into the cable again your mileage may vary. also assuming it is going to be a strait duplexer you have an additional 0.8 to 1.5 dB of loss as well as loss for the jumpers required to put it all together. best case scenario would be in the 27-30W at the top making your ERP ~275-300w just sayin' good luck w/poject. JE

at 225 feet your losses wold be roughly 1dB for the 1 5/8 spec 0.44/100' loss 1.8 for the 7/8 spec 0.8/100' loss assuming 50W into the cable here is what you would have at the other side 39-40 W 1 5/8 33-34 W 7/8 again these are book specs your mileage may vary.