Simulcast

Chris0516

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The question I have is in regards to simulcast. I was listening to Cary/Wake25 last night with my 436HP. I know that the SDS100 is better with simulcast. But, I was wondering if simulcast, sometimes behaves with the same reception fluctuation, that AM radio has? During the day, reception is weaker. Than it is at night. At least that is what I have been hearing(and not hearing).

RFI
TIA
 

wtp

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Port Charlotte FL
in a town of 5,000 i would not figure that excessive RF is the problem.
i have simulcast problems and some talkgroups seem fine as they talk. others are hit and miss.
there is no logic to it, it just is. and yes they had let go of the mic, so they were using different frequencies.
but no so with some others. and the radio works great, out of my neighborhood.
and that is another telltale sign.
 

Chris0516

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in a town of 5,000 i would not figure that excessive RF is the problem.
i have simulcast problems and some talkgroups seem fine as they talk. others are hit and miss.
there is no logic to it, it just is. and yes they had let go of the mic, so they were using different frequencies.
but no so with some others. and the radio works great, out of my neighborhood.
and that is another telltale sign.
Where I live, the pop. is less than 2,600. When it comes to RF, the trees' make up for the lack of pop., ugh.
 

Randyk4661

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Many AM radio stations drop their power at night to make way for what are called "Clear Channel Radio Stations"
CCRS stations maintain a 50,000 watt power 24/7 and can be (when conditions are right) heard across the country.

Not sure if this is still in effect but if you use a AM car radio and search the band you are more likely to receive radio stations well out of your area during the night time vs daytime. It also helps if you are in a remote area of the country vs a large metropolitan area.
During the 70's we could hear a NYC news station in Los Angeles after 10pm.
 

AA4BK

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Feb 9, 2018
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I'm surprised you're seeing much of a difference at all at those frequencies. Propagation at typical P25 frequencies (usually 700/800 MHz range) is pretty consistent regardless of the hour as far as I know. It surprises me that you'd really see a consistent change based on the time of day. I'm not saying you aren't seeing it, I just am surprised is all.
 

AA4BK

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Many AM radio stations drop their power at night to make way for what are called "Clear Channel Radio Stations"
CCRS stations maintain a 50,000 watt power 24/7 and can be (when conditions are right) heard across the country.

Not sure if this is still in effect but if you use a AM car radio and search the band you are more likely to receive radio stations well out of your area during the night time vs daytime. It also helps if you are in a remote area of the country vs a large metropolitan area.
During the 70's we could hear a NYC news station in Los Angeles after 10pm.

They actually used to be permitted 500,000 watts at least at night, for the clear channel stations. Yes, half a million watts! As a child I used to listen to stations hundreds and thousands of miles away every night as a hobby. It was a lot of fun trying to catch the signal as it faded in and out. But they got backed down a while back. I haven't tried it in a while now, and I'm not sure how well it works now as a hobby since they did get their power reduced by a large amount. I think you're right about 50,000 watts being the max now.
 

hamstang

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Charlotte NC
The question I have is in regards to simulcast. I was listening to Cary/Wake25 last night with my 436HP. I know that the SDS100 is better with simulcast. But, I was wondering if simulcast, sometimes behaves with the same reception fluctuation, that AM radio has? During the day, reception is weaker. Than it is at night. At least that is what I have been hearing(and not hearing).

RFI
TIA
My experience with the Charlotte Mecklenburg UASI system and a BCD996XT was yes reception was variable day to day. Temperature inversions are frequent, and tend to enhance VHF and above propagation. Acquiring an SDS200 solved the simulcast issues for me as expected, and I was amazed how much I had been missing. I had tried all the antenna tricks including paper clips and an outdoor yagi antenna with the 996 with not much improvement.
 
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