Ooook. Now i'm starting to question the functionality of my radio

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AggieCon

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With simulcast, it isn't necessarily signal strength that is the problem.

Linear Simulcast Modulation uses amplitude and frequency modulation concurrently. I also assert that it drops the power to near zero between symbols. I think this messes the scanners up.

I didn't mention, but keep the orientation and location of the radio in mind. For me, the craziest things will work. I really wish I had pictures. And experiment with a pizza pan or cookie sheet below the scanner. Even tilting the scanner in a certain setting can be the difference between problems and perfect decode to me. And the jokes about standing on one foot... that's not too far off. Your body acts as a good shield, so it can block the wanted signal or interference. It's almost silly what is sometimes required to get these to work on simulcast.
 

jetscanner

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With simulcast, it isn't necessarily signal strength that is the problem.

Linear Simulcast Modulation uses amplitude and frequency modulation concurrently. I also assert that it drops the power to near zero between symbols. I think this messes the scanners up.

I didn't mention, but keep the orientation and location of the radio in mind. For me, the craziest things will work. I really wish I had pictures. And experiment with a pizza pan or cookie sheet below the scanner. Even tilting the scanner in a certain setting can be the difference between problems and perfect decode to me. And the jokes about standing on one foot... that's not too far off. Your body acts as a good shield, so it can block the wanted signal or interference. It's almost silly what is sometimes required to get these to work on simulcast.
Oh I know. 10 minutes before you posted I was moving sheet of tin foil around. At a specific position I can get trunk data/talk from Fort Bends simulcast. Somewhat garbled, but its a first. No luck with any other phase 1 sites.

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AggieCon

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Feel free to email me your v-scanner configuration if you want me to take a look.
 

AggieCon

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I saw those, but if I am going to complete a favor, it would need to be in a more efficient fashion.
 

jetscanner

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I saw those, but if I am going to complete a favor, it would need to be in a more efficient fashion.
Ill get it over to you when im back on a machine.

So you suggest using a pc over commercial scanners eh? Any specific RTL-SDR dongles you recommend on amazon? Additional antenna?

Spent 45 min trying to position a yagi. I get a steady trunk signal at a tiny, tiny corner, but its still broken up.

A real pain in the



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AggieCon

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If you have a decent PC, then, yes, that should be the cheapest and best option.

For SDR:

Best one: http://amzn.to/2mziyLp
- temperature stable timeclock
- SMA connection
- "better" antenna
-gets wayy hot

Still good, but cheaper: http://amzn.to/2mhdElh
- will have to determine frequency drift

Antennas:

My favorite for mobile: http://amzn.to/2mhgwP0

Yagi: http://amzn.to/2m1uGDk (for SDR or scanner, will need adapter or pigtail)

Try the SDRs first with the stock antennas, even if you get the cheaper blue ones, the small antennas might just do the trick. Find a pigtail to go from whichever SDR you get to BNC so you can use your scanner antennas with the SDR.
 

jetscanner

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If you have a decent PC, then, yes, that should be the cheapest and best option.

For SDR:

Best one: http://amzn.to/2mziyLp
- temperature stable timeclock
- SMA connection
- "better" antenna
-gets wayy hot

Still good, but cheaper: http://amzn.to/2mhdElh
- will have to determine frequency drift

Antennas:

My favorite for mobile: http://amzn.to/2mhgwP0

Yagi: http://amzn.to/2m1uGDk (for SDR or scanner, will need adapter or pigtail)

Try the SDRs first with the stock antennas, even if you get the cheaper blue ones, the small antennas might just do the trick. Find a pigtail to go from whichever SDR you get to BNC so you can use your scanner antennas with the SDR.
Those all look good. And cheap.

V-Scanner with control channels only. Except clodine, I just added that and didnt L/O the sites.

http://www.filedropper.com/cdatvs004
 

jetscanner

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If you have a decent PC, then, yes, that should be the cheapest and best option.

For SDR:

Best one: http://amzn.to/2mziyLp
- temperature stable timeclock
- SMA connection
- "better" antenna
-gets wayy hot

Still good, but cheaper: http://amzn.to/2mhdElh
- will have to determine frequency drift

Antennas:

My favorite for mobile: http://amzn.to/2mhgwP0

Yagi: http://amzn.to/2m1uGDk (for SDR or scanner, will need adapter or pigtail)

Try the SDRs first with the stock antennas, even if you get the cheaper blue ones, the small antennas might just do the trick. Find a pigtail to go from whichever SDR you get to BNC so you can use your scanner antennas with the SDR.
Are you able to get bcso and fbso sheriff 100% with the sdr/software?

Ever get them 100% with a scanner?

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AggieCon

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I am not near Fort Bend County so I can't speak to that. With a scanner, if I am in a "sweet spot," I get BCSO 100% while in that spot. If I am out driving around, it's nothing near 100%.

SDR it's not a problem. *** it could potentially be a different story where you are.

Taking a look at your v-scanner config...
 

AggieCon

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Okay, I looked at your scanlist. You are certainly on the right track. Good job putting that together. A few tips:

-> Add all of the known talkgroups for each system, even if you are not interested in them. That way you know what they are when you use a wildcard.
-> Add a wildcard to each system.
-> On scalist 1, you have two different systems included.

I would delete the unwanted frequencies rather than locking them out. Move the control channel to the top.

Once you get it going, for an hour or so you can hit skip on the talkgroups you are not interested. Then go through and look those out in the EZ Scan configuration.

Scanner positioning and using a directional antenna are the main considerations I can think of at this point. For what it is worth, inside, I have to be creative with the Whistlers to get perfect decode on the Brazoria LSM site. When I am driving, it is perfect, good, or dead, depending on where I am.
 

AggieCon

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There was a post that was for some reason deleted. To answer your question: You would certainly want a P25 Phase 2 TDMA capable scanner for this area.
 

jetscanner

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Heres a final update for the inevitable pour soul in the future that learns about LSM.

Long (oh so long) story short

It was LSM after all and not the scanner. This was finally confirmed after a drive deeper into the nearby county.

Thanks to the RS 800mhz antenna, I found a corner outside my house that seems to gets flaky trunk data. Speech was garbled but still hope. There was no way the stock antenna would have accomplished that.

Finished building my 11db yagi via k7mems site and now get a full signal and solid trunk data went pointed to the simulcast site about 16-20 miles away. Has been steady since.

Now, I guess I enjoy it before everything becomes inevitably encrypted one day.



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buddrousa

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Keep up the hard work JET and keep us updated so it may help others like you.
 
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