Reception and tips to improve it. (LAPD LASD CHP)

Chuy_01

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Hi, I Have a question on how to improve reception Mainly for LAPD but also for LASD, CHP

I Live in the San Fernado Valley (Pacoima/Arleta area)
I have a Uniden BCD325P2 The Antenna I use is a TRAM 1094 3ft in length mounted on top of my roof

for LAPD I can hear all of VALLEY Bureau and CENTRAL Bureau
I cannot hear anything of WEST Bureau and for SOUTH Bureau, I can Sometimes hear some activity but not always.

for LASD I can hear everything Except South LA/ Marina Del Rey and Lancaster / Palmdale

for CHP I can hear all of the offices in LA County, Expect BALDWIN PARK

If anyone has any tips (Especially for LAPD south/west Bureau), I am simply out of luck geographically, or is there something I can do hear these frequencies, any help would be appreciated!
 

tsalmrsystemtech

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All I can say is get a big discone antenna since you need all band and that's about all you can do unless you buy a directional antenna like a Griddy Antenna I use to point striaght up to SBDCO Mountain Simulcast System and it works beautiful.

What is difficult for you is probably your location as you can't recive everything. That's normal for everyone. Since you are looking for VHF Low Band and UHF-2 band and you either go with directional antennas for the certain band you want or you use a discone all band. I guess your TAM 1094 I think from looking is a mag mount for your car. You need more metal in the air and as high as you can get.
 

FrensicPic

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What you describe is similiar to my experience in the West SFV with an old VHF-High quarter-wave groundplane at 20 feet. Those "distant" bureaus/areas coverage is designed for for those areas; they are not transmitting to cover the entire city/county.
Take a look at the terrain (mountains) around you that may be blocking distant signals.
About all you can do is get an antenna up as high as you can and/or a directional antenna aimed in the direction of the area of interest.
 

Chuy_01

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All I can say is get a big discone antenna since you need all band and that's about all you can do unless you buy a directional antenna like a Griddy Antenna I use to point striaght up to SBDCO Mountain Simulcast System and it works beautiful.

What is difficult for you is probably your location as you can't recive everything. That's normal for everyone. Since you are looking for VHF Low Band and UHF-2 band and you either go with directional antennas for the certain band you want or you use a discone all band. I guess your TAM 1094 I think from looking is a mag mount for your car. You need more metal in the air and as high as you can get.
Yup I agree I was originally going to mount it on my car, but I decided to Temperly mount in on the roof, on top of my AC Unit, to test it, and it works really well, for what I can hear, CHP and LASD especially sound very clear with little interference. and surprisingly I'm able to catch San Deigo pd on their 800MHz system, I unfortunately can't hear San Deigo's pd/county 700MHz system. other things I found was that sometimes I'm able to catch Ventura and Oxnard PD, however this isn't the case always, I wonder how that works maybe weather interference or something not sure how that works, same goes with LAPD South Bureau I can sometimes hear them other times I don't.
 

Chuy_01

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What you describe is similiar to my experience in the West SFV with an old VHF-High quarter-wave groundplane at 20 feet. Those "distant" bureaus/areas coverage is designed for for those areas; they are not transmitting to cover the entire city/county.
Take a look at the terrain (mountains) around you that may be blocking distant signals.
About all you can do is get an antenna up as high as you can and/or a directional antenna aimed in the direction of the area of interest.
Yes, probably even worse for you since you live in the west SFV, where there're taller mountains. I always thought LAPD had citywide repeaters, but maybe I'm remembering wrong. at least there's LAPD Hot Shot Dispatch witch kind of connects you to the rest of the city, Also LASD Access channel 483.5625 will sometime rebroadcast stuff from other divisions, however it's not as frequent as LAPDs hotshot.
 

tsalmrsystemtech

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Bottom line is you need lots of long metal in the sky to absorb the radio waves. Lots and high as possible. You would be surprised what kind of metal you can put in the air besides a commerical grade antenna and things work. Lots of metal and high as possible. I use to bury antennas up in high up trees that were higher than the roof line of my house.
 

Engine104

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I live in the WSFV too. I have a discone in the attic. I'll can verify what Chuy_01 wrote: I can't hear any of the West LA LAPD divisions. There is a Hot Shots frequency listed in the database that will work and let you hear any priority calls citywide. LASD is going to be very limited now that they are moving to LA-RICS. I'm still hearing LASD Malibu/Lost Hills dispatch on their old UHF frequency for now. Most of the talk groups, all of the L-Tacs and A-Tacs, will be encrypted. At this time, they plan to keep the dispatch frequencies in the clear, but that can change.
 

AM909

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Over the years, simulcasting, reduction in power levels, and pattern shaping have been added to a lot of systems (especially UHF+) to direct more of the signal where it's needed and less where it isn't. The days of just blasting hundreds of watts 360 degrees around to cover SoCal like swiss cheese (anybody remember the Dick Van Dyke voice identifier?) are mostly gone, I think.
 

Ubbe

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For a normal size discone they usually change its radiation pattern a lot when going above 500MHz. So much that it might even be better to use a rubber or telescope antenna directly on the scanner inside the house. If a single scanner must be used to cover all frequency bands then something like a diplexer can help that switch the signal to another antenna for frequencies above 600MHz, maybe a single band vertical with some gain, or a yagi that will be a lot cheaper if all signals comes from one general direction. At the 800MHz band a discone's radiation diagram can look something like this, where it picks up most of its signal from ground noise:

images


/Ubbe
 

Navy9545

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Thank you for your original post Chuy_01. I read it with interest, because I too live in the same area as you, with several scanners: a Radio Shack Pro-106, a Uniden BCD436HP, and a SDS100. My antenna is an AntennaCraft ST2 mounted on a pole about 25 feet above the roof. I currently use approximately 70 of RG-11 coax. Unfortunately, I too get the same reception as you. On good days, I can receive CHP all the way to San Clemente. San Diego PD and the military trunked systems also generally come in. We owe this reception to the Santa Monica and San Gabriel Mountains, I presume.

The only success I have had in expanding my range of reception has been switching to the ST2 when at home and to a Diamond SRH77 when mobile. I have also used run of the mill coax from Fry's to LMR-400. I did notice a discernable difference when I switched from RG6\RG58 (I forget) to name brand RG-11 (including proper grounding and leak proofing the coax connectors). I didn't notice a difference between the RG-11 and LMR-400. Of course, all my experiences are based on my hearing and not scientific.

LAPD does have citywide repeaters, but only on their citywide tacs 1-5 & 7 (6 having been assigned to transit services division) as well as many of their specialized unit frequencies.

I have a 100 foot (+/-) or so pine tree on my property and would love to mount something up there. Alas, my disabilities, age\wisdom, and fear of heights prevent from climbing up.

Incidentally, years ago I drove up the top of the Santa Monica Mountains\Hollywood Hills (Mulholland Drive) and the reception was, of course, night and day with any of my HT antennas.
 

tsalmrsystemtech

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Thank you for your original post Chuy_01. I read it with interest, because I too live in the same area as you, with several scanners: a Radio Shack Pro-106, a Uniden BCD436HP, and a SDS100. My antenna is an AntennaCraft ST2 mounted on a pole about 25 feet above the roof. I currently use approximately 70 of RG-11 coax. Unfortunately, I too get the same reception as you. On good days, I can receive CHP all the way to San Clemente. San Diego PD and the military trunked systems also generally come in. We owe this reception to the Santa Monica and San Gabriel Mountains, I presume.

The only success I have had in expanding my range of reception has been switching to the ST2 when at home and to a Diamond SRH77 when mobile. I have also used run of the mill coax from Fry's to LMR-400. I did notice a discernable difference when I switched from RG6\RG58 (I forget) to name brand RG-11 (including proper grounding and leak proofing the coax connectors). I didn't notice a difference between the RG-11 and LMR-400. Of course, all my experiences are based on my hearing and not scientific.

LAPD does have citywide repeaters, but only on their citywide tacs 1-5 & 7 (6 having been assigned to transit services division) as well as many of their specialized unit frequencies.

I have a 100 foot (+/-) or so pine tree on my property and would love to mount something up there. Alas, my disabilities, age\wisdom, and fear of heights prevent from climbing up.

Incidentally, years ago I drove up the top of the Santa Monica Mountains\Hollywood Hills (Mulholland Drive) and the reception was, of course, night and day with any of my HT antennas.
I love elevation when I travel to Crestline I can hear Kern County FIRE from like over a 150 miles away crystal clear on VHF at 6K feet elevation. Couldn't believe it. Mostly all of their FIRE calls are great ones especially in their rural areas around all of their farm lands. Also, can hear Long Beach PD and FIRE too. Jaw dropping sometimes.
 

Chuy_01

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*update* Thanks for all the responses, I finally bought a proper dicone Antenna and I also bought an SDS100 and it did improve some of my reception issues. First thing I can now hear CHP Baldwin Park so all of LA county CHP is clear for me, in addition I can hear Ventura/Moorpark CHP clear.
I can hear CHP Rancho Cucamonga, Arrowhead / San Bernardino and Riverside but they come in fairly choppy.

As for LASD I can now hear South LA/ Marina Del Rey (comes in fairly Choppy) and Lancaster / Palmdale (comes in Extremely choppy)
also sometimes get weird interference and hear LA County FD or something? I'm not sure.

As for LAPD still. completely radio silent, For South and West Bureau
 
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