Trouble Receiving 800mhz

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SCPD

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I just purchased the st-2 antenna and have mounted it to the roof of my house probably near 30 feet high.
The st-2 works great on receiving conventional frequencies both close by and further away.
The issue i have is that anything on the 800 band will not come in. At the best the scanner will stop on a frequency, and make a little noise but nothing resembling a voice. The 800 MHZ system i am trying to reach is from my town, and neighboring towns- nothing crazy and nothing far away.
I am able to pick up these same 800 frequencies with my radioshack 800mhz antenna pretty well.
The St-2 is connected by the 50 feet of coax it came with and is connected to a Radio Shack Pro-651.
I have tried using attenuation with no success, and if it matters I am in Rhode Island trying to pull in Glocester PD. (Not Gloucester)
Any idea on what i can do to improve my 800 reception with this antenna. It seems as if the problem is with the antenna, as the Radio Shack 800 mhz antenna works well receiving the 800mhz transmissions. I want to use the st-2 antenna because of its good performance with the conventional frequencies.
The scanner shows the frequency at almost full signal when it locks on, but with no voice to be heard.
Thanks in advance for the help.
 
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teufler

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are you trying to receive the Rhode Island State Rescon? If so, it has to be set up as a digital system. 3 sites in the system, for Providence cty. You may have a simulcast problem, try each site and assign a key to each so you can select each site. Sometimes less signal is better than more signal. To check, pick a system, say 35 or more miles away from you, if you can detect, you can hear.. Open the squelch 100%, see if you get background hiss or noise.
 

W8RMH

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What type of coax are you using? Times Microwave LMR-400 is recommended on a 50 foot run for 800 MHz.

Also are there any cell phone towers nearby? They can block and/or interfere with 800 MHz. signals.
 

msrettinger

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I doubt it has any to do with your ST-2 Antenna, unless you have a bad connection. I have a ST-2 about 30 feet in the air and use the coax that came with the antenna connected to my Uniden BC15X. I have a tower less than a mile from my house and I also monitor another tower about 35 miles from my house. The tower 35 miles away has just as strong of signal, according to the bars on the scanner, it comes in perfectly clear. It must be something with the type of system you are trying to monitor or your programming in your scanner.
 

bailly2

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So nothing if you search 851 to 869? For picking up glocester PD
On the rescon trunked system its highly recommended you get
A yagi antenna for 850mhz since that system uses simulcasting
Which causes distortion
 

dave3825

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I am able to pick up these same 800 frequencies with my radioshack 800mhz antenna pretty well.

It seems as if the problem is with the antenna, as the Radio Shack 800 mhz antenna works well receiving the 800mhz transmissions.

The scanner shows the frequency at almost full signal when it locks on, but with no voice to be heard.

That system has 3 tower sites. What site are you scanning?
North, south or Providence City?

Have you tried scanning one at a time. Also the system is digital, and now you have a much better antenna. That might change the p25 decode rate settings you are using. I would first try scanning just 1 of the 3 sites, and play with the decode settings. Just write down what settings you are using now so you can restore them if need be..
 

SCPD

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So here's what I'm thinking. Since I have all 3 sites programmed, the new antenna is picking up two sites for the RISCON system which is causing the interference. If I program just one site in the interference will end. I will try tonight. There was a big accident in my town last night and I heard nothing from the PD while on the st2 but heard well on the radio shack antenna, so I must be picking up two sites causing interference. Does this sound like a real problem? Will try tonight. Thanks everyone
 

bailly2

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even if you just program one site your still going to get distortion. with LSM multiple towers transmit at the same time on the same frequencies, so you need an antenna like a yagi to limit reception from all the towers except one
wiki.radioreference.com/index.php/Simulcast_digital_distortion
 

SCPD

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I programmed the north site only in, it worked. The 800 frequencies come in better than they did with the radio shack antenna, and I also am still receiving a very clear sound from the conventionals with better range than the Radio Shack antenna (obviously). Thanks everyone for the input.
Dan
 

SCPD

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Turns out that the problem remains unfixed. Heres what I have done:
I found that on the control channel I am getting very low decode rates, almost 40%. I took it upon myself to roate the antenna, and that had no positive impact. While on the roof I had the scanner with me, attached to a 800 MHZ mobile antenna from radio shack. The antenna performed excellent from up there, the decode rate was from 90-99 and the voice was readable for digital and analog. This all was for about 20 minutes, until I finished what I had to do. From inside the 800 MHZ antenna doesn't perform where I need it to on the analog frequencies, so it isn't an option from inside the house although outside it performs well. The ST2 that I adjusted isn't getting it done for the RISCON system here. Has anyone had success in improving decoding rates greatly, just from switching cable? I'm eyeing the LMR 400 that has been popularly discussed, it would be replacing the rg6 that I currently have running (50 Feet)
As mentioned at the start of the thread, I'm scanning RISCON for Scituate, Glocester, Burrillville police departments. The surrounding fire departments on Analog are loud and clear. Also still using pro 651.
 

ecps92

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Actually you have the 3 Zones Programmed
Each Zone has multiple Sites, which is causing your Multi-Path issue

Scanners are not designed to handle the multi-path distortion

I would look at the FCC data for each Zone and try and determine which tower/Site is closest and aim a beam at that tower



So here's what I'm thinking. Since I have all 3 sites programmed, the new antenna is picking up two sites for the RISCON system which is causing the interference. If I program just one site in the interference will end. I will try tonight. There was a big accident in my town last night and I heard nothing from the PD while on the st2 but heard well on the radio shack antenna, so I must be picking up two sites causing interference. Does this sound like a real problem? Will try tonight. Thanks everyone
 

SCPD

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Actually you have the 3 Zones Programmed
Each Zone has multiple Sites, which is causing your Multi-Path issue

Scanners are not designed to handle the multi-path distortion

I would look at the FCC data for each Zone and try and determine which tower/Site is closest and aim a beam at that tower
When I analyze the 3 sites, I am only picking up one site. Is it possible to have multi path distortion if you're only in range of one site? My guess would be no.
 

tampabaynews

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I don't have a Radio Shack but I've had luck using various combinations of 800mhz yagis, setting the squelch to zero, and/or using the built in attenuator setting.
 

JoeyC

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When I analyze the 3 sites, I am only picking up one site. Is it possible to have multi path distortion if you're only in range of one site? My guess would be no.
Don't confuse simulcasting transmit sites for zones. You may be in range of only one zone that you are listening to, but you are likely in range of several sites within the zone. So yes, you can be a victim of multipath distortion by listening to only the North, South or Providence City simulcast.

This is all very confusing as each zone is listed as a site in the RR database. Each zone (site) can have several transmitters simulcasting the same signal on the same frequency within it that causes the digital distortion.
 

ecps92

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I am Basing this response on RISCON and prior experience with RISCON and Scanners

Actually you are picking up 3 different Zones.
Each Zone has more than one Site
You need to view the Licenses and aim your antenna at the best site, experiment as the closest might not be the best

North
needs to be updated with the NEW Call Sign, but WQGG803 (North Providence, Town of) FCC Callsign Details was 3 different Sites (Not Zones)

South
under WQEE894 (Rhode Island, State of - Emergency Management Agency) FCC Callsign Details is 5 different sites

Providence is
WQEE893 (Rhode Island, State of - Emergency Management Agency) FCC Callsign Details for 4 different sites and was using WQLZ263 (PROVIDENCE, CITY OF) FCC Callsign Details with 5 different sites.

As pointed out, do not confuse Sites with Zones
Think of it like Cellular Phones. You are in Rhode Island (Zone) but connected to the tower at 123 main st (site) Zones can have many sites


When I analyze the 3 sites, I am only picking up one site. Is it possible to have multi path distortion if you're only in range of one site? My guess would be no.
 

SCPD

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So I gave in and decided to order a yagi. This I wanted to be my last resort, because i'd like to use one antenna and one scanner, but it looks as if I'll be purchasing a different scanner and pairing it with the Scantenna. Anybody know of cheap analog scanners that display the tags on screen? I've searched around with no finds, so I may settle for the 652 at my local RS thats closing at the end of the month.

The yagi should be here Friday and thats where I'm going to try pointing it at the three different sites for the North zone. The one on right off of 102 is the closest to my house, so I guess thats where I will be starting. I'm hoping to mount it in the attick or near a window, as the bees are back in the spot where my coax runs from the exhaust vent, good thing it's sealed up.

Once thing I noticed, was that when I put a paperclip into the scanner I started showing constant 98% decode rate, and incredibly clear audio. It's late at night and I've only heard a few transmissions, but I'm starting to think i'm onto something. I've looked at corner antenna reflectors also, and everything is starting to come together in my head, or so I think. As the research I've done, my original thoughts with aiming the antenna at the 102 site is that it shouldn't be pointed directly at the site, in order to block out signals from the two other sites from the North Zone. I will attempt this and post back my findings.

Thanks everyone for the input, I'm learning more and more in my spare time, and am really enjoying the hobby even though the simulcast stuff can be difficult at times.

Dan from Rhode Island.
 

jimijodie

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So I gave in and decided to order a yagi. This I wanted to be my last resort, because i'd like to use one antenna and one scanner, but it looks as if I'll be purchasing a different scanner and pairing it with the Scantenna. Anybody know of cheap analog scanners that display the tags on screen? I've searched around with no finds, so I may settle for the 652 at my local RS thats closing at the end of the month.

The yagi should be here Friday and thats where I'm going to try pointing it at the three different sites for the North zone. The one on right off of 102 is the closest to my house, so I guess thats where I will be starting. I'm hoping to mount it in the attick or near a window, as the bees are back in the spot where my coax runs from the exhaust vent, good thing it's sealed up.

Once thing I noticed, was that when I put a paperclip into the scanner I started showing constant 98% decode rate, and incredibly clear audio. It's late at night and I've only heard a few transmissions, but I'm starting to think i'm onto something. I've looked at corner antenna reflectors also, and everything is starting to come together in my head, or so I think. As the research I've done, my original thoughts with aiming the antenna at the 102 site is that it shouldn't be pointed directly at the site, in order to block out signals from the two other sites from the North Zone. I will attempt this and post back my findings.

Thanks everyone for the input, I'm learning more and more in my spare time, and am really enjoying the hobby even though the simulcast stuff can be difficult at times.

Dan from Rhode Island.
I am having the same issue with my pro-651 just in a different state, can you tell me what yagi you ordered and if it helped ?
Thanks, Jim
 

SCPD

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This is what i purchased http://www.amazon.com/gp/product/B00L3ZRF9A/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

The yagi is in the attic currently, and I'm getting varying results. I can go a few minutes locked in on 98% readings, and then five minutes later it'll read 50% for ten seconds, and jump to 60, 80 and everything in between. So whats going on? I'll keep adjusting until I find a spot that provides a more consistent reading. I do think that what I have heard is better than before for the most part.
 

SCPD

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Not by any means declaring success, but I think I found a solid spot. The scanner is reading 99% pretty consistently with some 92's mixed in and higher 80's. I'll be listening tonight to decide, but I'm pretty amped up at this point. Thanks for the input everyone
Dan
 
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