Question about DSD

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corbintechboy

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Hello,

Tax time is approaching which gives me an excuse to buy a new toy. I live in an area where NXDN is taking over. Here is my question:

If I get a P25 scanner (looking at the PSR-800 since it has disc. output) and program in NXDN channels, since it is digital will it stop on the NXDN signals? Of course without the ability to decode within the scanner itself?

I am thinking if I get a conventional scanner and use DSD I will have to leave it parked on a channel and wait for a transmission to be decoded? Whereas with a digital I will actually be able to scan and have it decoded on the fly?

Am I correct in my thinking?
 

n5ims

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DSD will work the exact same with an analog scanner and a digital scanner. The fact that the scanner will decode other types of digital signals isn't relevant to how the scanner will feed the signal to DSD. If the scanner won't decode NXDN on its own, its extra digital circuits won't help DSD do any of the decoding work.

If DSD requires the scanner be parked on a channel to wait for a signal to be decoded, it will require an analog scanner to be parked as well as a digital scanner to be parked. There is no difference.
 

corbintechboy

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DSD will work the exact same with an analog scanner and a digital scanner. The fact that the scanner will decode other types of digital signals isn't relevant to how the scanner will feed the signal to DSD. If the scanner won't decode NXDN on its own, its extra digital circuits won't help DSD do any of the decoding work.

If DSD requires the scanner be parked on a channel to wait for a signal to be decoded, it will require an analog scanner to be parked as well as a digital scanner to be parked. There is no difference.

Thanks for the reply.

My question really is will a digital scanner stop on another digital signal (NXDN)? DSD does have the ability to decode on the fly, the problem comes from the scanner internal circuits. A conventional scanner will not even stop on a P25 signal (unless really close) where a a P25 scanner will stop scanning on a P25 signal (and I am hoping any digital signal).

If I have to buy a scanner to monitor one station through DSD, I am not interested. I will be interested if a P25 scanner will stop on digital traffic.

I guess my question is not really about DSD so much (it can decode on the fly), but more about the abilty for a scanner to actually scan digital systems.
 
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rbrtklamp2

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even the top of the line scanners will only decode p25 phase 1 right now the psr800 claims to decode p25 phase 2 but with the recent release of the phase 2 standard I dont know if that statement is correct anymore due to phase 2 being different from X2-TDMA digital tranmissions. no scanner on the market will decode NXDN, TRBO, OR IDAS. but the psr 800 does have a built in discriminator tap and will stop on the channels carrying digital traffic even if it cant decode you will just hear the data noises. with regards to no analog scanner will stop on p25 or other digital formats unless you are close is not a true statement i hae a tapped pro 163 that decodes everything from p25 to IDAS with DSD and all kinds of other good stuff like pagers and acars and mdts marine and land gps signals. like I said you can use a good analog scanner to decode any signals you want as long as you have it tapped but the psr800 is a great scanner with really good p25 decoding and the added benefit of having a discriminator tap already built in so there is no need for scanner surgery. bottom line no scanner will decode anything but p25 but the psr800 will work with dsd to decode other types of digital transmissions as well very nicely.

I hope this answered some of your questions if not pm me and i will try to be a little more specific,
Bob
 
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