P25 phase 1 and phase 2 tdma compared

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vocoder

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So i have a p25 phase 1 LSM and a phase 2 TDMA LSM that are the same distance from me. I scan on a regular basis using an outdoor discone and tdma scanner.

Why is it the phase 2,TDMA system receives better than the phase 1?

I expected the other way around, phase 1 should RX better?
 

troymail

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So i have a p25 phase 1 LSM and a phase 2 TDMA LSM that are the same distance from me. I scan on a regular basis using an outdoor discone and tdma scanner.

Why is it the phase 2,TDMA system receives better than the phase 1?

I expected the other way around, phase 1 should RX better?
Some folks (including me) many times see just the opposite. Assuming you're talking about two different systems, you can't really compare one system to another like that -- there's just way too many variables.
 

ScannerSK

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A few blocks away a neighbor may get just the opposite results. It all depends upon how steady and strong the signal strength arriving at the scanner is from the repeater(s).

Shawn
 

vocoder

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One system is the county and other is a large city trs. And actually i think the p25 phase 1 LSM has more watts!
 
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ScannerSK

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Trees or other objects can creating ghosting or picket fencing signal artifacts (which distort the decoding capabilities of our scanners) on one signal while not upon another signal. This is especially noticeable in the higher frequencies such as 800's and 900's MHz.

Also, if a single repeater is being predominately received from the LSM system then the scanner will receive it for all intents and purposes as a non-simulcast signal. I found the perfect spot for my scanner (next to my computer tower) which apparently blocks signals from one direction while not from another direction. It's about the only spot in my house where I get constant good reception on our simulcast system.

Shawn
 
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DaveNF2G

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Now that all of the sites are operating on one of the cells of the county next door's Phase 1 LSM system, I get one control channel signal that overwhelms all of the others, so I get consistently good reception more than 90% of the time.
 
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