A question regarding towers and MARCS

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N8NCX

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Driving down the major interstate arteries I see regularly spaced towers that have a couple microwave parabolics near the top along with some other verticals. Are these part of the MARCS system? And if so are they of any use to the scanner? MARCS isn't received that great inside my home with the stock antenna.
I'm maybe 15 - 20 miles from the controllers. One is better than the other as far as signal quality goes. But if these tower relay MARCS across the state, why can't they be an advantage for the listener? Seems like a simple digital scanner doesn't possess the sophistication needed to function well ie allowing the listener to
travel and not have to know what controllers serve the areas. There should be some kind of automatic roaming one would assume.
 

W8RMH

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Driving down the major interstate arteries I see regularly spaced towers that have a couple microwave parabolics near the top along with some other verticals. Are these part of the MARCS system? And if so are they of any use to the scanner? MARCS isn't received that great inside my home with the stock antenna.
I'm maybe 15 - 20 miles from the controllers. One is better than the other as far as signal quality goes. But if these tower relay MARCS across the state, why can't they be an advantage for the listener? Seems like a simple digital scanner doesn't possess the sophistication needed to function well ie allowing the listener to
travel and not have to know what controllers serve the areas. There should be some kind of automatic roaming one would assume.

Uniden's location-based scanning uses GPS to allow you to control which systems/sites and channel groups are scanned based on your exact location. This frees you from having to manually enable and disable sites as you change location. Specifically, location-based scanning uses the scanners lockout function to control what is scanned based on your location. It unlocks systems, sites, or channel groups when you are inside an element's radius. When you exit the radius, the element is temporarily locked out. The HP-1, BCD996T, BCT15, BCT15X, and all XT's have this ability.

MARCS pretty much requires a 800 MHz antenna for reliable reception.

As far as a scanner receiving microwave signals between controllers I don't think that is possible.
 
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RonnieUSA

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Rowan County,KY (Morehead)
Driving down the major interstate arteries I see regularly spaced towers that have a couple microwave parabolics near the top along with some other verticals. Are these part of the MARCS system? And if so are they of any use to the scanner? MARCS isn't received that great inside my home with the stock antenna.
I'm maybe 15 - 20 miles from the controllers. One is better than the other as far as signal quality goes. But if these tower relay MARCS across the state, why can't they be an advantage for the listener? Seems like a simple digital scanner doesn't possess the sophistication needed to function well ie allowing the listener to
travel and not have to know what controllers serve the areas. There should be some kind of automatic roaming one would assume.
The Home Patrol with GPS.
 

N8NCX

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Uniden's location-based scanning uses GPS to allow you to control which systems/sites and channel groups are scanned based on your exact location. This frees you from having to manually enable and disable sites as you change location. Specifically, location-based scanning uses the scanners lockout function to control what is scanned based on your location. It unlocks systems, sites, or channel groups when you are inside an element's radius. When you exit the radius, the element is temporarily locked out. The HP-1, BCD996T, BCT15, BCT15X, and all XT's have this ability.

MARCS pretty much requires a 800 MHz antenna for reliable reception.

As far as a scanner receiving microwave signals between controllers I don't think that is possible.
Who makes it?
 

budevans

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Or you can create MARCS scanlists for the major interstates. I have MARCS scanlists for i71 and i77.

I use the i71 scanlist when I go from Cleveland to Columbus or Cinncinnati.
 

N8NCX

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Uniden's location-based scanning uses GPS to allow you to control which systems/sites and channel groups are scanned based on your exact location. This frees you from having to manually enable and disable sites as you change location. Specifically, location-based scanning uses the scanners lockout function to control what is scanned based on your location. It unlocks systems, sites, or channel groups when you are inside an element's radius. When you exit the radius, the element is temporarily locked out. The HP-1, BCD996T, BCT15, BCT15X, and all XT's have this ability.

MARCS pretty much requires a 800 MHz antenna for reliable reception.

As far as a scanner receiving microwave signals between controllers I don't think that is possible.
I can rx MARCS in the mobile using a dual band U/V Comet CSB 750A antenna in my driveway. There's a hot spot about halfway from the garage where the signal is 99%. But a Cushcraft AR270B dual band base antenna mounted 30 feet in the air does a worse job than the telescopic antenna. I have an older Antenna Specialists scanner antenna that has an 800 mhz cylinder on the vertical portion but no mount for it. I think it has a course threaded 5/16 end on it. I bet that mounted under the Cushcraft by about 10 feet would do well. I'd just need to buy some more cable and to keep the loss down at 800 you need either
Belden 9913 or 7/8 hardline and both are expensive. My problem is inside the house and having a 100 foot hill that has a lot of trees in the way of the controllers. Now that the leaves are gone I have noticed
a better quality signal. And the only thing I need MARCS for is my town's fire and EMS which have switched to MARCS for some reason while the rest of the city remains conventional.
 

mtindor

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I'd venture to say a simple Radio Shack 800 Mhz antenna will outperform anything you currently have. It really is amazing the difference between stock antenna and an RS 800 Mhz ducky.

As far as your antenna at the house, it does not suprise me that you say it does worse. I have a 2m/440 Diamond X300a up 40ft, and I can pick up more MARCS towers, with better quality, using the RS 800 Mhz on the scanner sitting in the basement. And I run LMR-400 coax, N connectors and use a preamp [at times].

The cheapest way to improve your sig is to be a $20 RS 800 mhz antenna. Then if you need more after that to make you happy, you'll need to get a 800 mhz antenna for outside and use some decent (LMR-400 or equiv) coax to keep your losses as low as possible.

If your location is the lat/long in your profile, there is no reason you shouldn't pick up 3 or more MARCS sites from your location, not to mention all of the other 800 mhz systems in your county.

Mike
 

N8NCX

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I'd venture to say a simple Radio Shack 800 Mhz antenna will outperform anything you currently have. It really is amazing the difference between stock antenna and an RS 800 Mhz ducky.

As far as your antenna at the house, it does not suprise me that you say it does worse. I have a 2m/440 Diamond X300a up 40ft, and I can pick up more MARCS towers, with better quality, using the RS 800 Mhz on the scanner sitting in the basement. And I run LMR-400 coax, N connectors and use a preamp [at times].

The cheapest way to improve your sig is to be a $20 RS 800 mhz antenna. Then if you need more after that to make you happy, you'll need to get a 800 mhz antenna for outside and use some decent (LMR-400 or equiv) coax to keep your losses as low as possible.

If your location is the lat/long in your profile, there is no reason you shouldn't pick up 3 or more MARCS sites from your location, not to mention all of the other 800 mhz systems in your county.

Mike
If I move the scanner just 6 feet across the living room it picks up MARCS fine. So I guess here by my easy chair is a dead spot. I tried the duck from my RS Pro 95 analog dual trunker and it did no better
than the stock GRE PSR 600 telescope. If I still had the darn mag base for the A/S scanner antenna that does 800 and stuck it on a metal ammo box on my other end table by the wall I'd bet that would solve
my problem. I have a Diamond SG 7500 on a mag mount inside my bedroom on a steel 5.56 NATO ammo box and it does a fantastic job on 2 and .70. I don't have downlead in my bedroom for the AR270B but sometimes I like to sit at the computer in my bedroom and use the radio. With 50 watts I've got a 1.5:1 SWR starting at 146 mhz and at 35 watts on .70 a 1.1:1 on 442.00. I might look for that A/S mag mount and see if the scanner antenna does a better job. Tonight the telescope is doing just fine for MARCS. A steady 4 bars and very little swooshing. So I'm just on the edge here for the 2 Stark county
controllers. Stark's county system is received five bars at 99% quality so they are not a problem. Also an LTR system and EDACS for American Electric Power come in well. So it's actually just one MARCS controller that is a bit too low. LOL I can even move the scanner around on the table beside my easy chair and get an extra bar on the s-meter bumping the rx quality up to 89% where the swoosh is livable.
 

mtindor

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It makes sense that on 800 mhz you can effect a nice change in signal strength by moving a few feet here or there [sometimes even inches]. Up in that range, a wavelength is only 1', plus or minus.

I can easily have extremely poor reception in one spot and then move 3" and have have a 3+ bar improvement.

I still stand by my claim that the RS 800 Mhz duck is the best bang for the buck antenna improvement one can make for 800 mhz. Beats any stock scanner antenna for 800 mhz reception. Of course, if you don't need it you don't need it -- and it sounds like you don't need it :)

Mike


If I move the scanner just 6 feet across the living room it picks up MARCS fine. So I guess here by my easy chair is a dead spot. I tried the duck from my RS Pro 95 analog dual trunker and it did no better
than the stock GRE PSR 600 telescope. If I still had the darn mag base for the A/S scanner antenna that does 800 and stuck it on a metal ammo box on my other end table by the wall I'd bet that would solve
my problem. I have a Diamond SG 7500 on a mag mount inside my bedroom on a steel 5.56 NATO ammo box and it does a fantastic job on 2 and .70. I don't have downlead in my bedroom for the AR270B but sometimes I like to sit at the computer in my bedroom and use the radio. With 50 watts I've got a 1.5:1 SWR starting at 146 mhz and at 35 watts on .70 a 1.1:1 on 442.00. I might look for that A/S mag mount and see if the scanner antenna does a better job. Tonight the telescope is doing just fine for MARCS. A steady 4 bars and very little swooshing. So I'm just on the edge here for the 2 Stark county
controllers. Stark's county system is received five bars at 99% quality so they are not a problem. Also an LTR system and EDACS for American Electric Power come in well. So it's actually just one MARCS controller that is a bit too low. LOL I can even move the scanner around on the table beside my easy chair and get an extra bar on the s-meter bumping the rx quality up to 89% where the swoosh is livable.
 

N8NCX

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It makes sense that on 800 mhz you can effect a nice change in signal strength by moving a few feet here or there [sometimes even inches]. Up in that range, a wavelength is only 1', plus or minus.

I can easily have extremely poor reception in one spot and then move 3" and have have a 3+ bar improvement.

I still stand by my claim that the RS 800 Mhz duck is the best bang for the buck antenna improvement one can make for 800 mhz. Beats any stock scanner antenna for 800 mhz reception. Of course, if you don't need it you don't need it -- and it sounds like you don't need it :)

Mike
I'll probably put something up on my HF vertical tripod outside. It Won't need much but unity gain and a little height. A 1 - 1300 Discone probably would do just fine and since we're looking under 50' of coax, RG213 or even RG8X would probably work ok. I'd just hate to spend the money for 9914 or 9913.
 

mtindor

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I'll probably put something up on my HF vertical tripod outside. It Won't need much but unity gain and a little height. A 1 - 1300 Discone probably would do just fine and since we're looking under 50' of coax, RG213 or even RG8X would probably work ok. I'd just hate to spend the money for 9914 or 9913.

It's your money. I like to wring every last dB out of my setup. Then again, I don't scan to listen to local traffic -- Everything I listen to is DX. So I have to have the last dB.

Mike
 

N8NCX

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It's your money. I like to wring every last dB out of my setup. Then again, I don't scan to listen to local traffic -- Everything I listen to is DX. So I have to have the last dB.

Mike
I don't DX on public service. As a matter of fact I'd rather not hear anything that doesn't happen in Stark County. I get my fair share of 2 way DX on 10 meters where this week I've worked Slovenia, Italy, Bavaria, Czech Republic, UK, Netherlands and a bunch others that don't come to mind. And when 10 isn't jumping, 15 and 20 are and later on 40. Can only work digital those three but I've got a TNC and can do Baudot/RTTY, Morse, and Amtor and work either domestic or a hole other part of the world. Thanks for the suggestions everyone who replied It's not etched in stone as to what my final choice will be. I sure would love to set up a magnetic base that I could thread that Antenna Specialist's MON-52. You see the pic of it here Antenna Specialists MON-52 That antenna sold for $143 at one time and it's the one with the steel 800 mhz choke right below the center coil. That antenna sitting on a mount with three counterpoise of the right length mounted to the peak of my front porch roof would actually be the best for me. I'd only need about 25 feet of coax if that. I guess I'll take to a friend who has the metal machinery to make me a mount and maybe just go that route. I already have 30 spare feet of 9913. Whatever I decide I may come back and update. We can go ahead and close this thread now.
 

w8prr

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800mhz

Whatever antenna you use, the cable is the key. LMR400 LMR 600 or even 1/2 inch hard line.

I am about 40 miles from the Dayton site and 45 miles from the closest Columbus site and get both very well with 5 el comtelco beams with LMR 600
 

N8NCX

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Whatever antenna you use, the cable is the key. LMR400 LMR 600 or even 1/2 inch hard line.

I am about 40 miles from the Dayton site and 45 miles from the closest Columbus site and get both very well with 5 el comtelco beams with LMR 600
Been a ham since 1991 so I know a little bit about feedline. I use RG8-X on my 6 meter Ringo AR-6,
9913 on my AR270B, and RG8 on my 4BTV HF. 9913 is about the best bang for the buck in Vhf/Uhf and if you're under 50' 800/900 as well. So yeah I'm not going to put up a high gain antenna just to lose it all in the dowlead :)
 

dizwiz

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In my experience, MARCS (and other 800 MHz systems) are heavily affected by interference from other similar freq systems (cell towers, etc.).

At first, you might think you are getting a bad signal because of your distance from the tower, but in reality there is a competing signal from a cell tower, or something else.

Ive hit the attenuator button, mid sentence in a MARCS conversation, and have had things remarkedly improve on my PSR-500. Especially when driving mobile in urban areas - or rural highway areas when a cell tower comes into sight.

On the flipside, Ive hit the attenuator (ATT) button and have had decode go down quite a bit. In that case, its obvious that the MARCS tower is far away and I should turn the ATT back off and let the PSR-500 seek out a better system during roam mode (via other tower channels programmed in ) .
 
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