794.1125 Smartzone in Navasota area?

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rattlerbb01

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OK, I know that there are sometimes frequency hits that are caused by interference, or IF, or whatever. But I am picking up a Motorola SmartZone control channel, 3600 BPS, on 794.1125 with my Pro-96 in the search function from here in Navasota. It is strong enough it bleeds over onto 794.11875 also. It is clear as day, yet is not found in an FCC search. The only 800 MHZ station we have within ten miles is an Entergy tower with a Control Channel on 858.8875. I tried programming it and seeing if it would show up with a system ID, yet nothing. I guess it wont ID anything on 700 mhz.

Any clues?
 

MMIC

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The only Motorola systems that support 700 MHz in trunking are the ASTRO-25 releases, which are all 9600 baud. They have not, and will not, be releasing a 700 MHz system in 4.1 or earlier releases (3600 baud).
 

rattlerbb01

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Which makes me think that I was hearing some kind of intermod/image/technical interference that I have no idea what I am talking about, so that is why I am looking for possible answers from the more experienced techs/hams on this forum. If you take the antenna off my scanner, you can still pick up the Entergy CC on 858.8875 fully (93-99%). Mathematics puts the 794.1125 at 64.775 MHZ below the output, and 19.775 MHZ below the input, which of course is quiet unless a field unit keys up, and then only for a split second. Could it just be something inherent in the Pro-96?
 

loumaag

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If you program it as a MOT frequency and set the bank to MOT then hold on the CCh with MAN it will report the SysID. You can then look it up if it is in the DB here.
 

rattlerbb01

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Done that, doesn't show up at all. Does anybody from the New Orleans area that has monitored 700 know if a Pro96 has worked showing CC system ID?
 
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loumaag

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rattlerbb01 said:
Done that, doesn't show up at all. Does anybody from the New Orleans area that has monitored 700 know if a Pro96 has worked showing CC system ID?
I have and it does. That is why I told you to try the above. If it isn't showing then it isn't a MOT CCh.
 

rattlerbb01

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It is still going. And it sounds just like any other Smartzone CC. Same diesel engine sound, with the old five pulses and a buzz repeating over and over. Even caught a couple of bounces in the sound indicating activity. Forgive me if these are not technical terms, but like I said, I am not a ham or programmer or software writer, so the most I know is how to identify SmartNet from SmartZone, or EDACS 4800 Baud from 9600 Baud. My BC785D is now tapped and reading all of the above great with unitrunker, but I can't get the 700 band with the BC785D, and I don't feel comfortable tapping my Pro96 with it's plastic case and all.
If any one has a tapped unit capable of receiving 700, give this one a try. The ducting was so good last night that I picked up every Starnet site from ground level with the Pro96 with at least a 90% decode rate. I am sure someone can pick up this from the Houston area on nights like last night.
 

loumaag

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I will repeat, the Pro96 will report correctly on channels in the 700 MHz range. As others have said, there are no Motorola Smartzone(or net) systems in the 700 MHz PubSfty range so you are either hearing an image (unlikely because it would still report) or you are hearing a LP TV transmission or remote data transmission, since that is in the spectrum for that type of transmission.

794.1125 would be the input channel for 762.1125 which falls on the "odd" channel number part of the spectrum whereas most P25 systems are using the "even" channel numbers presently; that would be 764.10625 or 764.11875. However in no case would you hear a CCh on the input side.
 

rattlerbb01

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Thanks. I am not trying to be difficult, I just wanted confirmation that I am hearing an "image." I can't seem to find a copy of the bandplan for 700 anywhere. I would still like someone with a different radio (396 or 996) to see if they pick it up though. Just to put my mind at ease. I am only a mile from the Entergy Navasota site 415 tower, so I imagine it puts off enough ERP to make funny things happen with scanners.
 

rattlerbb01

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add 792.9375 to that. must just be some problem with my scanner. nonetheless, i want to know if any one else with a pro96 picks up this kind of stuff. I hear TV audio carriers in this band still mixed in.
 
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