HP-2: HP2 SDS100 Talkgroup

ROD

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Buckley, WA.
Scratching my head as to why i can listen to the SDS100 and HP2 side by side both parked on PSERN system, Talk group dept Seattle Police and hear communication on the SDS but not the HP2. I have line by compared the sentinel software for each scanner and everything seem to match. Just seems to be Seattle , I can hear all the other cities fine.
 

tvengr

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The PSERN system uses simulcast sites. The SDS100 and SDS200 were designed to eliminate the problems caused by simulcast distortion. The HP2 does not handle simulcast well. Simulcast distortion results in missed transmissions, garbled audio, and sometimes no reception at all. If you are using an outside antenna, disconnect it and use the scanner antenna. Try removing the scanner antenna and replace it with a paperclip. Simulcast distortion is very location specific. Try moving the scanner around the room. The problem is that simulcast sites actually consist of several subsites all transmitting on the same frequency at the same time. The signals from the subsites arrive at your scanner at slightly different times which degrades the scanner's ability to properly decode the control channel. If you are close to one of the subsites, it can override the out of phase interference from the other subsites. Anything you do to attenuate the signal may reduce the number of subsites you receive and improve control channel decoding. When dealing with simulcast, less signal is more. Take the scanner for a drive and see if it receives OK at certain locations. If it does, that will be a good indication of simulcast distortion.
 
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ROD

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Thank you very much for that information. I have began experimenting with the antenna and it is receiving again with mixed results.
 

hiegtx

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Dallas, TX
Thank you very much for that information. I have began experimenting with the antenna and it is receiving again with mixed results.
The City of Dallas, Dallas County, and a number of smaller towns have moved over to this regional TRS, which uses simulcast sites.

As has been noted a number of times, simulcast distortion can be extremely location specific, and with experimentation, you may find a location in your residence where the HP-2 does receive a fair amount of traffic despite simulcast issues.

What I've done, with my HP-2, in addition to moving the scanner around to try to find an optimal location, is to use the old OEM antenna, not one of the 'gain' antennas such as the REM-800B (which is the newer version of what we used to call the 'Radio Shack 800MHz antenna). I position the antenna horizontally, parallel to the desktop, not vertical. With it aligned in that manner, I get quite a few of the calls. Not 100% to be sure, but more than enough to at least be useful.
 

NWI_Scanner_Guy

SCANNING THE AIRWAVES SINCE 1987
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Jan 23, 2008
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Hammond, IN
What I've done, with my HP-2, in addition to moving the scanner around to try to find an optimal location, is to use the old OEM antenna, not one of the 'gain' antennas such as the REM-800B (which is the newer version of what we used to call the 'Radio Shack 800MHz antenna). I position the antenna horizontally, parallel to the desktop, not vertical. With it aligned in that manner, I get quite a few of the calls. Not 100% to be sure, but more than enough to at least be useful.

I'm going to give that a try with my HP2. I love my HP2 but yeah, it sucks when it comes to simulcast systems. Any "trick" that can make it more useful will be a good thing.

:)
 

mc48

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Monroe County, NY
Have you manually adjusted the decode in the hidden menu?

 

JoeBearcat

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I'm going to give that a try with my HP2. I love my HP2 but yeah, it sucks when it comes to simulcast systems. Any "trick" that can make it more useful will be a good thing.

:)

'Less antenna' is usually better for simulcast. You can also try attenuation.
 
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