800 mhz trunked Mass state police???

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bobruzzo

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I noticed the past few days my reception of the 800 mhz trunked system the Mass state police uses has been very staticy and more noise than signal. I live in Cranston RI and usually can hear them reasonably well. I use discone up 30' fed by 50' lmr 400. Radio is radio shack pro 2055. I am getting a NEW radio Monday, Bearcat BCT15X. I dont plan to go digital YET. Anyway has the Mass state police cut back power to the transmitters or something? I kinda miss listening to all the activity there. In addition to the noise on signal I am also not hearing much at all on that system! I have it programmed in scanner as Motorola type II smart zone. I was actually receiving this with a vhf vertical dipole last year before I got the discone! Using cable tv cable too! Now I dont hear much at all, and when there is a transmission, it is 75% noise. HELP!:cry:
 

cg

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No change that I have seen in Western MA. It is almost certainly at your end. Check all your connections. Test against a known signal like the various weather channels.

chris
 

ecps92

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Springtime. As the Temps warm, ICE becomes water and get's into external antenna feed lines, plus as we move more into Spring the leaves impact reception. Take a close look at your antenna connections, as well as the feed line, maybe a crimp/kink occured.

As CG indicate for Western MA nothing has changed, and from Eastern MA - reception is still the same

I noticed the past few days my reception of the 800 mhz trunked system the Mass state police uses has been very staticy and more noise than signal. I live in Cranston RI and usually can hear them reasonably well. I use discone up 30' fed by 50' lmr 400. Radio is radio shack pro 2055. I am getting a NEW radio Monday, Bearcat BCT15X. I dont plan to go digital YET. Anyway has the Mass state police cut back power to the transmitters or something? I kinda miss listening to all the activity there. In addition to the noise on signal I am also not hearing much at all on that system! I have it programmed in scanner as Motorola type II smart zone. I was actually receiving this with a vhf vertical dipole last year before I got the discone! Using cable tv cable too! Now I dont hear much at all, and when there is a transmission, it is 75% noise. HELP!:cry:
 

KEWB-N1EXA

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No change that I have seen in Western MA. It is almost certainly at your end. Check all your connections. Test against a known signal like the various weather channels.

chris
Have to say the Same for New Bedford I'm monitoring zones 3 and 4 with my Uniden 15X and a discone cut
for as low frequency of 125 Mhz. I also monitor zones 1 and 5 when up in Boston in the car with an old Uniden hand held.
I did try the other day my discone on my uniden 996P2 on IC&E's network up on 935 Mhz. I found Falmouth
and Fall River to be lower on the signal level than my UHF verticle which is a Diamond 901 with ground plane kit added.
So Ill say my Discone is the long arm on VHF and Fantasic on 300 MHZ military but as the frequency goes up so
does the radiation angle so perforemace at 800 and 900 Mhz gets Noisey and A lower signal.
Way out in Rhode Island Id say thats 30 miles to Acushnet Tower for State Police or some other tower on the network so the Discone may not cut it.
You may have to go to a 800+ meg Yagi or make a cut verticle for Smart Net Monitoring.

As for Coax your 75 Ohm RG 6 or 59 is OK your not transmitting down it so your not fighting impedance issues.

Just Pooh's ipinion your mileage may vary.

Peter N1EXA
 

garys

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I have noticed some fall off on signal strength for Zone 5 over the past few weeks. Not horrible, but noticeable.
 

KEWB-N1EXA

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I have noticed some fall off on signal strength for Zone 5 over the past few weeks. Not horrible, but noticeable.
Garys
The Guy moved to another forum and he said Zone 3 and seeing he just got the
15X on Saturday he is crashing through programming it. The 15X and 996 are not hard to program at all I use freescan or in the case of the 996P2 with DMR just bump the data in.

Pete N1EXA
 

kruser

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As for Coax your 75 Ohm RG 6 or 59 is OK your not transmitting down it so your not fighting impedance issues.

Peter N1EXA
He's using LMR 400 coax per his post.
I think the idea of water ingress could be the culprit here.

I've also had a hunk of LMR-400 go bad where it had come loose and was allowed to swing some in the wind during one winter. The constant swinging at the points between where it was still attached allowed the center conductor to break cleanly in two similar to how a coat hanger will break after you bend it back and forth a bunch. That one was a bear to find but once I saw that it had come loose, it was not as hard finding it by shorting one end and watching a meter on the other end while flexing the coax by hand.
Even though the center conductor had broken, many VHF stations still seemed fine but it really affected anything UHF and higher the most.
 

KEWB-N1EXA

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He's using LMR 400 coax per his post.
I think the idea of water ingress could be the culprit here.

I've also had a hunk of LMR-400 go bad where it had come loose and was allowed to swing some in the wind during one winter. The constant swinging at the points between where it was still attached allowed the center conductor to break cleanly in two similar to how a coat hanger will break after you bend it back and forth a bunch. That one was a bear to find but once I saw that it had come loose, it was not as hard finding it by shorting one end and watching a meter on the other end while flexing the coax by hand.
Even though the center conductor had broken, many VHF stations still seemed fine but it really affected anything UHF and higher the most.
Reading back at the first posting the RG6 was on the Verticle and the LMR400 was on the Discone. He is also listening to the MA State police which still uses Analog Smart Net trunking on 850 MHz in the next state over. That's A good haul. Now i'm A few miles from the SP tower so I don't even need an antenna to get them.
Ill Agree Coax is not as durable as you would think. It has to be secure it wicks water and if you kink it you get all kind of issues.
I have a Discone and some Verticles - You could spend all day talking about the
differences - I find the Discone to be fantastic up to about 400 Mhz then it really starts to roll off, Now not bad but Looking at a DMR site on 935 Mhz 10 miles
away i can go between both antenna's types and see the difference. I can see why Discone's are used by the military on UHF airband.
I'm just saying that The guy is 30 miles from A 850Mhz trunk tower using a Discone I'm amazed he can even get it.

Peter N1EXA
 

garys

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He should be hearing Zone 3, but of course there are a lot of variables that go into reception. I'm sort of on the border between the two Zones and get both fairly well as a rule. I can sometimes even get Zone 8.

No, the 15X is not hard to program at all.

Garys
The Guy moved to another forum and he said Zone 3 and seeing he just got the
15X on Saturday he is crashing through programming it. The 15X and 996 are not hard to program at all I use freescan or in the case of the 996P2 with DMR just bump the data in.

Pete N1EXA
 

kruser

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Reading back at the first posting the RG6 was on the Verticle and the LMR400 was on the Discone.
I'm just saying that The guy is 30 miles from A 850Mhz trunk tower using a Discone I'm amazed he can even get it.

Peter N1EXA
Ha! I did misread the mention of cable tv coax. I thought it said "tool" and not "too!"! Darn old age eyes.

I was going to ask him in his other thread how far he was but you just answered that. Yep, 30 miles is a haul, especially at 800 MHz.
They could have very easily changed to directional or panel type antennas for better coverage in the needed areas much like most simulcast sites are using today. Locals in the areas may not notice the change but the op probably would being outside the intended coverage area.

Oh well, hopefully he will get it all figured out.
 

bobruzzo

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Hi all...yep I did finally re-program the BCT15x with computer and also I checked coax. Only been out there 1 year. I know when I attached coax (lmr 400) to the antennna (discone) I waterproofed it with sealant and the connection is totally covered by the small mast section that came with antenna. So connection point is isolated from weather. Also the coax is secured so as not to move even in high winds. And also coax is secured all the way up into shack. I checked my indoor connections. I can still recieve all the distant UHF freqs out as far as Dighton, Mass. Everything comes in perfect except the 800 mhz Bristol system! I noticed over the past week when I was using my other radio, the pro 2055, reception for that 800 mhz system was getting weaker and weaker. There is more noise-to-signal. And much less traffic. And I do use a vertical dipole cut for aircraft and local monitoring. The reason I used TV coax is because when I built the dipole, I didnt have any radio coax but found a new 50' roll with F connectors in garage. So for the heck of it I just used that figuring I'd get something better shortly anyway. But the reception was so good I just left it. And yes I was able to hear the 800mhz trunked system on that antenna too. Not as good of course. Anyway I have troubleshooted on my end as much as I can. I ended up deleting that system from scanner since I cant hear it anymore. When I was hearing it ok the signal was mostly always about 75% signal and 25% white noise. And there is a substantial hill to my east blocking the signal a bit. Now if I go up on that hill which is about a mile and a half from here, at the top I can hear EVERYTHING perfectly even 800 mhz trunked systems from elsewhere. So even if the agency cut their power, it may still be perfectly audible on that hill, but not for me being in the shadow of the hill.
 

bobruzzo

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Here is a crude map I made showing where I have heard from at my location. All the signals I have received over in Massachusetts were UHF and I heard them perfectly with minimal noise, if any. The black arrow is where my house is. I have a hill to my east. Not sure where the transmitter location is for Troop D Mass SP trunk system. I can also hear lowband (33 mhz) fire depts over west in Ct.
 

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Firefox10

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From Merrimac Valley, zone 5 on my 436hp, and 15X, i've noticed more static than normal and a bit of loss of sensativity. I heard a trooper the other day on direct 2, say "these radios have seen their day, they are getting worse with the static." He mentioned a new trooper got a new radio so their should be on their way to all, "but his sounds worse than mine in some locations"
I gather their is "something" off.
 

ecps92

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Depending on where in the Valley [Lowell/Chelmsford to Amesbury/Salisbury] there has always been Zone 5 issues, which is why they added Zone 20 [Haverhill] years ago to fill in that coverage.

From Merrimac Valley, zone 5 on my 436hp, and 15X, i've noticed more static than normal and a bit of loss of sensativity. I heard a trooper the other day on direct 2, say "these radios have seen their day, they are getting worse with the static." He mentioned a new trooper got a new radio so their should be on their way to all, "but his sounds worse than mine in some locations"
I gather their is "something" off.
 

n1nlr

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The other thing to keep in mind when comparing reception between different frequency bands is that your free space loss goes up as your frequency goes up. This is on top of the usual feedline loss issues.

30mi path at
851 MHz 124.7 dB loss
451 MHz 119.2 dB
154 MHz 109.9 dB
 

bobruzzo

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The other thing to keep in mind when comparing reception between different frequency bands is that your free space loss goes up as your frequency goes up. This is on top of the usual feedline loss issues.

30mi path at
851 MHz 124.7 dB loss
451 MHz 119.2 dB
154 MHz 109.9 dB
I understand but what I am saying is I was able to hear this system for the last year with no problems. Now I can no longer hear them reliably. I tested out the other radios and antennas. And in the beginning around Jan 2019 when I first started to listen to this system, I was receiving with a vertical dipole cut for aircraft!
 

n1nlr

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I understand but what I am saying is I was able to hear this system for the last year with no problems. Now I can no longer hear them reliably. I tested out the other radios and antennas. And in the beginning around Jan 2019 when I first started to listen to this system, I was receiving with a vertical dipole cut for aircraft!
Good luck with sorting that out.
Mysterious changes like that are so frustrating to track down.
 

W1KNE

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Any possibility you are getting overload from the new TV signals in Rehoboth?
WJAR transitioned to uhf 25, and WLNE to 24 in mid December, and WSBE came on 2 in early January.
 

bobruzzo

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Any possibility you are getting overload from the new TV signals in Rehoboth?
WJAR transitioned to uhf 25, and WLNE to 24 in mid December, and WSBE came on 2 in early January.
I am about 20 miles from Rehoboth Mass. so not sure if thats the case, however I did notice a sharp decrease in signal around late Jan, early Feb. I checked out the control channel and its not even there anymore. Control channels have a characteristic sound. But for the last year I had been recieving the 800 mhz trunk system Mass state PD reasonably well considering there is a hill to my east....right in line with southeastern mass. I was even originally recieving in using a vertical dipole cut for aircraft band. On a 20' bamboo pole! Now there's nothing there, no control channel sounds, no nuthin!
 

KEWB-N1EXA

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I am about 20 miles from Rehoboth Mass. so not sure if thats the case, however I did notice a sharp decrease in signal around late Jan, early Feb. I checked out the control channel and its not even there anymore. Control channels have a characteristic sound. But for the last year I had been recieving the 800 mhz trunk system Mass state PD reasonably well considering there is a hill to my east....right in line with southeastern mass. I was even originally recieving in using a vertical dipole cut for aircraft band. On a 20' bamboo pole! Now there's nothing there, no control channel sounds, no nuthin!
I'm not the brightest on this trunking system but I looked at the map at RR on Bristol/Plymouth Zone 3 and the diagram
shows 5 sites....Living in New Bedford I receive the Acushnet tower ( Site #1 ) at full signal. But looking at the Diagram
tower Site #5 is in the Attleboro area so i would think that is the Closest to you seeing your in Cranston.
Is this site down ? or modified ? something changed ...

here is the link




Peter N1EXA
 
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