SDS100 trouble tracking Utah Motorola system 420F

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522

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Like you said gldavis, lots of traffic this morning.
Here is another example:

 

jonwienke

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Auto will slow down scanning, as it has to try every filter setting every time it changes frequencies, which slows scanning down to 1/2 normal speed or less. Try Normal, then Invert, instead of the Auto settings.

Also use a SDR to sweep the region around the problem freq. There's a pulsating aspect to the static that sounds like interference, almost like a sped-up version of the pulsating static you see with the cold solder joint problem.

It would be more helpful if you posted a video of the actual transmission being received, instead of the Replay.
 
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tvengr

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If you have any other scanners on or your SDR, turn them off. You could be receiving a signal from the oscillator in another scanner or your SDR.
 

522

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I only used Auto Filter for this particular situation. Tried all the other Filters with the same result.

I'll try an SDR sweep later tonight or tomorrow morning.

No scanners or SDR on at the time of recordings.

Meanwhile, here is a live transmission clip, not a Replay:

 

jonwienke

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Your scanner is doing something odd--note there is no D-ERROR value showing, which should be "0" or some other numeric value when receiving a digital transmission, never "---".
 

jonwienke

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You see the same thing in my scanner with the cold solder joint issue in this video; the D-ERROR never shifts off "---" even when scanning control channels, where you should see a numeric value momentarily while control channel data is being processed.
 

522

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But... this System is Analog
 

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522

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Sorry @jonwienke .... I honestly was not trying to be condescending. I definitely appreciate everything you provide on this forum.

Do you think this D-ERROR was caused by something else?
 

gldavis

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I have three other different trunking scanners, and a conventional scanner. The all have clear audio when traffic is on this freq.
 

Ubbe

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I was thinking about the IFX, but didn't want to fool with it, until I'm more familiar with the cause and effect of making such a change.
It wont hurt you to use IFX. This sounds as a typical SDS interference problem, I have several of those when the spectrum have transmissions that are close to each other and a transmission some 100-200KHz away are interfering.

Do Channel button+enter the frequency+Channel button and then Fn+7. The display will show ifx if you have detailed display on. Then push the "to Scan" button. Do the same process again to remove the IFX from that frequency.

/Ubbe
 

jonwienke

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IFX can't damage anything, and if you try it and it doesn't work, you'll be no worse off than you are now.
 

gldavis

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I turned IFX "on", for 856.7125 (distorted freq) and 857.7125 (control channel). Audio still distorted on the 1 freq. This is becoming very puzzling. I'll put a call-out on the UTAH forum. See if anyone else has this issue (other than 522).
 
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