spurious transmissions?

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stratocaster
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spurious transmissions?

Post by stratocaster » 22 Jan 2018, 08:44

whilst on the scanner, I've been noticing spurious signals breaking through registering as dPMR or D-Star but only for a second and sounding completely garbled. Usually they break through on the 453+ mhz nfm range. Occasionally D-CR will register as well. Any thoughts as to this erroneous signal bleedthrough?
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owza
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Re: spurious transmissions?

Post by owza » 24 Jan 2018, 12:19

Possibly something really close to you, overloading the input of the scanner? Are you in a built up area? Taxi's, utilities etc?

stratocaster
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Re: spurious transmissions?

Post by stratocaster » 25 Jan 2018, 12:46

@ Owza, yes I am in a very built up area, practically city centre. If I could find the source of these bleedthrough transmissions and locate them on their natural bandplan, then I'd programme them in! I may have to attenuate the scanner to possibly cut out this bleedthrough, but found it unusual due to the massive 250-300 or so Mhz gap in bandplan bleedthrough.
I'll run another search from the scanner of the D-Star bandplan range and see if I can trace any culprits there, but it'll be a bit of patience required to grab the D-CR and dPmr culprits since I haven't noticed any dPmr activity near me so far on the dPMR bandplan.
My other thought is that as you point out a transmission overload. Therefore overloading the front end and confusing the system hence registering as various modes of DV transmission formats?
This is Broadsword calling Danny boy..

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