Signal Question

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chris480

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1. Sometimes PHX PD comes in with 4 or more bars, then most of the time it comes in with 1 or broken up. MCSO comes in usally with 3 or more bars most the time. From what I understand im not that far from a tower for PPD. Anyone know what I can do to tweak my scanner without a roof set up? ALso why would the radio for the units be able to pick up by my house if i cant? Dont the use same towers?

2. I hear all of the fire dispatch but never hear the units out on the chan they were told to be on, i dont even hear them clear. I dont understand why I dont hear them dont the still talk to dispatch? How is dispatch able to hear them?
 
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1) It sounds like you are a bit far out for perfect reception on PPD, maybe you have a few hills in the way. First try one of the GRE or Radio Shack or Antennex 800 mhz ducky antennas, that should give you another bar or maybe even two. If you really want a rooftop antenna AFTER trying those things, I will be happy to point you in the right direction but that is a subject all it's own, so maybe try the duck antennas first?

The radios the units use cost a few thousand dollars and for good reason. They are top notch motorola units and work a bit better than scanners due to a better front end. Also be aware that they have reception issues too sometimes.

2) You should be hearing fire dispatch come through OK sometimes, and really scratchy other times. The transmissions from North Mountain (7th street and thunderbird) should come in pretty well. These will be for north valley calls. The south valley calls come in from South Mountain I believe, and are pretty scratchy for those of us up north. In your location you may not even be hearing those at all. At Deer Valley & 19th Avenue (my work location) the south transmissions are pretty bad. As far as hearing the units it is a matter of line of sight. They don't use repeaters like the Police do. They just transmit from their radios, and the dispatcher can hear it because her tower is a thousand feet or so above the surrounding terrain. There is nothing blocking her signal, but there almost always is something blocking it for you, because your antenna is 5' off the ground as you hold your scanner (unless the fire vehicle is a block away from you). ******Note that Phoenix Fire will be switching to the same system PPD uses soon, they are currently working out a few "details".

For myself, my antenna is on a mast mounted on the peak of my house, and is about 40' above ground level. I can hear the fire units within a 8 mile radius or so, give or take a bit depending on what is between us with their location (trees, buildings, etc.). I still can't hear the ones 20 miles away unless they are up on a hill, or unless a good storm rolls in so the signals can reflect off the clouds.

Outdoor antenna's are beautiful things. No matter how good my handheld scanner works with it's stock antenna or where it is at, it cannot compare to the quality of signal and sound I get from my base scanner hooked up to a rooftop antenna. I have different outdoor antennas including one for 800 mhz aimed especially for Phoenix PD (which also gets the other 800 mhz agencies just fine), and vhf and uhf antennas mounted up high for those frequencies. I can pull in any agency on any band as well as can be expected, most crystal clear with awesome audio. This took hours of work and several hundred dollars of materials, but was worth it to me.

Start simple and get that duck. Then if you want to play further I can tell you just what you need to get the best reception in the valley.
 
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chris480

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Also what the dif between the ducky you are telling me to get and the one that came with my unit?
 
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There are antennas built just for 800 mhz (what PPD uses), and the one on your radio is made for ALL frequencies, so it is a compromise, and not optimal for 800 mhz.

As far as missing the old days of scanning, I do too for different reasons than you might, but keep something in mind.

You will hear MORE overall on the new PPD digital system than you would have heard on the old. Yes, they will encrypt car to car and tactical stuff, and you won't hear most of the detective stuff (you could hear all of that before the new system), BUT you will hear both sides of conversations on the regular traffic channels (A & B Dec), something you wouldn't have been able to do with your location on the old system. It would be just like the fire department, you wouldn't hear the units hardly ever with regular traffic, unless they were REALLY close. The new system is actually a cool thing for scanner users once you figure out what do do for the best reception in your individual case.

Back in the old days at my old house I had a 70' tower just so I could hear a good portion of the PPD units in the field on regular traffic.

Oh yeah, and don't forget Scottsdale PD, they are fun to monitor too, and barely use any encryption so you can really hear almost everything they do short of SAU.
 
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chris480

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Wow 70' tower! Im going to have to get that 800Mhz ducky this week because this drives me crazy. MCSO is great though. Should I try a different tower I am trying the one on Tatum, I am north of JoMax on tatum, closer to cave creek road. THis is my first real attempt since moving here, in NM i listend to a lot of stuff. I have been here over a year and just getting back into it now that I got the digital rig!
 
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You can't "choose" a tower. There are several all broadcasting the same thing at (almost) the same time, so they all hit you. The "almost" is the catch, because being at different distances, if three sites for instance are hitting you, they are slightly out of phase, so the scanner gets confused. The closest you can come to "choosing" a tower is putting up a yagi and aiming it so that the one closest (usually) comes in strong, the the others are attenuated (weakened) enough that they don't interfere with the one you want.

MCSO is different because it's sites use different frequencies. Simulcast A has the same frequencies broadcast from all sites at the same time, so don't confuse the two methods, they are different.

See this thread for all of the details.

http://www.radioreference.com/forums/showthread.php?t=106057

It is a lot of reading, but once you finish you will fully understand the issue, and the solution.
 

chris480

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SO should I have all of the simulcast freqs in my scanner? Right now I only have to two primary freqs for the Tatum location.
 
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These frequencies are used on ALL sites for Simulcast A:

201 Simulcast A: Phoenix PD 867.06250 867.17500 867.21250c 867.26250 867.38750 867.41250 867.68750 867.71250 867.76250
867.87500 867.91250 867.96250c 868.16250 868.18750 868.23750 868.33750 868.48750 868.51250


The Tatum site is just one of many sites all using the same frequencies transmitting the same thing, at the same time.

Simulcast B and other simulcasts do OTHER THINGS, NOT PPD.
 

chris480

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So I need all of those in to get everything? I only have the red and blue, thats what I was told by someone with all the Groups in, was told I only need the control chans.
 
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You should just need those that you mentioned, they are control frequencies. However I just type all of the frequencies in for reference. If you try monitoring that Thomson Peak list you are going to hear nothing though. Just use the Simulcast A frequencies.
 

chris480

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can i adjust anything on my scanner the 396t to try and get better ppd coverage? Or will nothing really help but the new ducky and maybe the other ants?
 
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You need to explore antenna options, there is no adjustment to increase the amount of signal reaching your scanner, or to compensate for interference from other simulcast sites.
 

chris480

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Im going to get the 800mhz ducky from radio shack, I also so this product whats your thoughts on it?
Super Amp HandHeld
 
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It's a good antenna with only positive reports. I have used it in the past (don't need it at this time), and it have about one bar more on average with 800 mhz systems. Some people report two bars on average. I have never heard anything bad about it.
 

chris480

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I was asking about the Super Amp, that goes on where your antenna goes then your antenna goes on it. You told me about the antenna I was just wondering if the $60 amp is really worth it or not.
 

ctrl

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I was asking about the Super Amp, that goes on where your antenna goes then your antenna goes on it. You told me about the antenna I was just wondering if the $60 amp is really worth it or not.

I personally dont know about the amp.

You probably need a yagi positioned correctly, like PHOENIX_SCANNER has mentianed.

Another good antenna is the radio shack vhf/uhf (#20-176 - $25) outdoor antenna. This works very well for general scanning. (look it up here on the forums for a TON of positive feedback) It might not help with the 800mhz, or it might make it better. I have this anntenna hanging inside of the house in the corner of a 2 story bedroom and it works good for everything. I trimmed about 1 inch off of one of the smaller verticals and it works decent on 800mhz to. I consider it a must have antenna for general scanning, and at 25$ its very hard to pass up.

For a quick/easy/cheap do it yourself job:
All it takes is a twist-tie wrapped around the tallest vertical and an eyehook screwed to the ceiling for a 'semi-temp' mount. (mines been up over a year)

I would try the ducky, and then the #20-176 before the amp. All else fails, a roof or possibly attic mounted yagi...
 
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chris480

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Yea trying the Yagi today! I dont want to go to outside ant because I like being able to walk around the house and listen in different areas! I would think that PPD would have great coverage everywhere in the city. Ever other city I have lived in has had excellent coverage!
 

wlmr

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Yea trying the Yagi today! I dont want to go to outside ant because I like being able to walk around the house and listen in different areas! I would think that PPD would have great coverage everywhere in the city. Ever other city I have lived in has had excellent coverage!

The short reply to your statement is that unfortunately for people with scanners, the system was designed to provide coverage to the people who use the system. The rest of us have to deal with where we are relative to where the users go.
 
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