MTR3000 Repeater

[kayn1n32008]

Yet Quantar, GTX, XPR and SLR repeaters have N and BNC connectors... Las repeater Motorola sold with SO-239 connectors were the MSR, or maybe the MSF(never dealt with that model). I doubt you can even order TxRx or Sinclair duplexers with PL-259/SO-239 connectors.

 

[jeepsandradios]

Is that feedline for inside shelter or up tower ? Personally I only use superflex inside the shelter then LDF up the tower. I guess a short run its ok.

 

[zerodayjames]

Is that feedline for inside shelter or up tower ? Personally I only use superflex inside the shelter then LDF up the tower. I guess a short run its ok.

It’s for both up the tower and in the shelter. 35 ft length will be up the tower and it will actually be helpful to have super flex as I’ll need to loop the end of it like this.



Is there a performance difference between the two?

 

[RFI-EMI-GUY]

It’s for both up the tower and in the shelter. 35 ft length will be up the tower and it will actually be helpful to have super flex as I’ll need to loop the end of it like this.

View attachment 155360

Is there a performance difference between the two?

That bend radius is a bit tight....

 

[zerodayjames]

That bend radius is a bit tight....

This was my first design using M&P Extraflex Bury 13 Premium .500.

I have another design idea that would allow it to go straight into the bottom of the antenna and avoid the loop. Just wasn't sure whether to roll with it or not. The loop also adds an extra 3ft of cable.

 

[jeepsandradios]

I see no reason to loops it thru the pipe.

As far as insertion loss -
FSJ - 450mhz 2.32db/100'
LDF - 450mhz 1.44db/100'

So not end of world but basically 1db difference. As said I've never seen FSJ run up a tower. Guess its done but I've never done it.

 

[zerodayjames]

I see no reason to loops it thru the pipe.

As far as insertion loss -
FSJ - 450mhz 2.32db/100'
LDF - 450mhz 1.44db/100'

So not end of world but basically 1db difference. As said I've never seen FSJ run up a tower. Guess its done but I've never done it.

It's looped because the pipe acts as both a support for the antenna as well as an enclosure. I did this because it is more aesthetically pleasing without having a cable running up the tower as well as easier weatherproofing when penetrating the roof.

I will redesign to remove the loop and use LDF

 

[mmckenna]

I've run superflex when it's a short run. I've got some small 10 watt UHF repeaters on mountain tops where I don't need a tall tower. A 10 foot length of 1 1/4 rigid conduit gets me up high enough. Out of the bottom of the enclosure and up to the antenna is about 10 feet total, so I used FSJ2-50 3/8". No need to transition, just straight run.

I agree, run it outside the pipe. You don't need the loop at the antenna end. Just waterproof it well, and use suitable UV rated zip-ties, or better yet, the stainless steel zip ties.

 

[zerodayjames]

1 1/4" rigid is some heavy stuff. I was originally going to use rigid for my tower but it was just too heavy considering I wanted it to extend for 2-3 lengths. In your case, 10ft 1 1/4" isn't so bad.

This is the design I came up with. I used 1 1/4" EMT with a 3ft. insert of 1" rigid. I tapped a total of 8, 1/4-20 holes and secured them with a bolt, lock ring and loctite. I plan on using this same method to extend it one more length for a total of 30ft. of EMT.

My idea to remove the loop will be to add a small 2ft. section of EMT as a secondary mounting point. I drew a basic idea below. I will also be incorporating guy lines at the 10ft and 20ft points. I was planning on using 1/4-20 eye bolts to replace the existing bolts.

 

[mmckenna]

Nice looking work.

OK, I see what you have to run it this way now. You might gain some space by using a weather head or an LB on top and looping the coax a bit larger. That would get the coax coming out ant a better angle and would help with weatherproofing.

I've got a similar install at our PD dispatch. The building has a steep pitch roof and some jackwagon architect decided he didn't like the looks of a tower. I lost the argument. They did roof jacks with 10 feet of 2" rigid conduit, about 5' of that sticking above the roof. A weather head on top to feed the cable out of, and a cross arm to support multiple antennas. It's been up for 10+ years and is still working well.

 

[zerodayjames]

Nice looking work.

OK, I see what you have to run it this way now. You might gain some space by using a weather head or an LB on top and looping the coax a bit larger. That would get the coax coming out ant a better angle and would help with weatherproofing.

I've got a similar install at our PD dispatch. The building has a steep pitch roof and some jackwagon architect decided he didn't like the looks of a tower. I lost the argument. They did roof jacks with 10 feet of 2" rigid conduit, about 5' of that sticking above the roof. A weather head on top to feed the cable out of, and a cross arm to support multiple antennas. It's been up for 10+ years and is still working well.

A weather head... genius... I can't believe I didn't even consider that. If I use a weather head I would be able to cut a ton of weight that added up from that rain tight connector, rigid coupling, reducing bushing, and cord grip. That way it won't be so damn top heavy and I can probably get away with using LDF too.

"Didn't like the looks" what a shame. Hey at least its still working over a considerable period of time. If I could get a legitimate tower on my roof I wouldn't hesitate haha.

 

[mmckenna]

and I can probably get away with using LDF too.

I'd stick with the FSJ. You want some flexibility where you connect to the antenna. LDF will be too stiff and you'll need a large loop to satisfy the minimum bend radius. Making a transition up there, and then again at the repeater, will eat up most of the losses you recover from the LDF. The fraction of difference would not be noticeable. Plus, the weather head will limit what you can do. The rest of your system looks really good, so don't stress over a fraction of a dB.

"Didn't like the looks" what a shame. Hey at least its still working over a considerable period of time. If I could get a legitimate tower on my roof I wouldn't hesitate haha.

It happens. No matter how tough others may talk, sometimes you have to make compromises. The architect was a guy that specialized in dispatch centers. I was not impressed with some of his choices, and actually having to move the dispatch center in there really showed how bad some of them were. But he'd done many PSAP's and this was my first. I lost.

But now we're replacing the radio system, and I'll probably get my tower added.

 

[jeepsandradios]

Agree with @mmckenna on sticking with FSJ for this application. Sorry I had thought I read this was going on a actual tower and not a pipe mast. The weatherhead is a perfect item. I have 1 1/4" thru the roof of my house for my DB224 and run the cable as well as 3 others thru the weatherhead. For the application above FSJ will be a good choice.

 

[zerodayjames]

FSJ it is. Appreciate the insight ya'll.

Well. The "cool" stuff is officially in. I'm currently waiting on a programming cable and for my Motorola account to verify so I can download the CPS and see what extra features this MTR3000 came with. There's IP address labels all over this thing so I'm assuming maybe CAPPLUS? I really only need it for DMR AES but I don't mind having extra features. Duplexer is massive. I still can't believe I found this new open box for $760 with free shipping. The "Sinclair" label is damaged but I suspect it was like that before it was shipped. I received it on a pallet with double cardboard packaging.

After I get familiar with programming the MTR next up will be to raise the tower, install the Hustler UHF antenna I was looking at and then purchase all of the equipment to start tuning this duplexer. Progress...

 

[Ubbe]

Loosen those hose clamps around the cans and let them drop to the floor and make a cutout where the three coax connectors are and push in the MTR in that hole and let it rest on the metal bar where the cans where sitting. The cans will be more accessible while tuning and your wrench wont be caught up on another can if they are loose and can be easily moved out of the way.

/Ubbe

 

[kayn1n32008]

FSJ it is. Appreciate the insight ya'll.

Well. The "cool" stuff is officially in. I'm currently waiting on a programming cable and for my Motorola account to verify so I can download the CPS and see what extra features this MTR3000 came with. There's IP address labels all over this thing so I'm assuming maybe CAPPLUS? I really only need it for DMR AES but I don't mind having extra features. Duplexer is massive. I still can't believe I found this new open box for $760 with free shipping. The "Sinclair" label is damaged but I suspect it was like that before it was shipped. I received it on a pallet with double cardboard packaging.

After I get familiar with programming the MTR next up will be to raise the tower, install the Hustler UHF antenna I was looking at and then purchase all of the equipment to start tuning this duplexer. Progress...

It may also been used in a conventional tional IP Site Connect system.

Any USB print cable should be sufficient to program the repeater, no need to buy a cable from Motorola. Your favorite, local computer retailer should have one, or you may already have one.

That duplexer is a very good piece of kit. Normally I'd use 4 or 6 cavity ResLok duplexers, but if you got it for a good price, all the better.

 

[zerodayjames]

Loosen those hose clamps around the cans and let them drop to the floor and make a cutout where the three coax connectors are and push in the MTR in that hole and let it rest on the metal bar where the cans where sitting. The cans will be more accessible while tuning and your wrench wont be caught up on another can if they are loose and can be easily moved out of the way.

/Ubbe

That's not a bad idea. I thought it was going to look like the one pictured in the documentation. Your idea would definitely help with easier tuning.

 

[zerodayjames]

It may also been used in a conventional tional IP Site Connect system.

Any USB print cable should be sufficient to program the repeater, no need to buy a cable from Motorola. Your favorite, local computer retailer should have one, or you may already have one.

That duplexer is a very good piece of kit. Normally I'd use 4 or 6 cavity ResLok duplexers, but if you got it for a good price, all the better.

Are you serious... I saw that it was the same configuration as a USB print cable but I was told that Motorola likely uses a proprietary pinouts for their cables so I spent $30 on a cable... It hasn't shipped yet so hopefully I can cancel that BS.

Yeah I got lucky for sure. The guy on eBay still has a couple more but he raised the price a couple hundred bucks after the last sale to me.

 

[zerodayjames]

I reached out to the eBay seller. It turns out the damage to the emblem occurred during shipping. Is it possible that this could have cause damage to the unit? Or more likely just potentially threw the tune off?

 

[mmckenna]

I reached out to the eBay seller. It turns out the damage to the emblem occurred during shipping. Is it possible that this could have cause damage to the unit? Or more likely just potentially threw the tune off?

It's possible, but I'd almost guarantee that if they were tuned before shipping, they no longer are.

Only way to know is to put them on a analyzer.

Do they rattle?