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drkatzjr

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I have always experienced an arduous time listening to the Link on OKWIN to OKCPD


Only me?
 

toad99

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If you can get a Uniden with the Provoice option, the OCPD will work very well. The OKWIN gives me a lot of simulcast distortion where I live, so I have to use directional Yagi antennas for OKWIN. I never notice any distortion on the OKC system, but the Provoice channels can have a wide variation in volume. Also, you will be able to listen to the OCFD directly.
 

toad99

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I see you are in Tulsa. How do you listen to the OCPD in Tulsa? I would suspect that if you are trying to pick up an OKWIN site in the OKC area that has OCPD traffic, you would have reception issues.
 

toad99

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I suspect that you are having simulcast distortion problems. The main transmitter site on the east side of OKC plus the Edmond site cause a lot of reception issues. A directional antenna is the only way I know of to avoid the problem. Any time I use a handheld or listen in my vehicle, simulcast distortion is terrible.
 

SCPD

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OKWIN Motorola Smartzone and OKCPD EDACS Provoice are in the same spectrum of frequency. EDACS is very strong. So strong it can desensitize your front end 'pulling' down on OKWIN weaker signals. I cannot count on my fingers, toes and maybe a few hairs on my head how many times I had to keep re-positioning my antenna while monitoring OKWIN until I cave in and switch Unitrunker to EDACS Provoice.

OKWIN and OKC Core and Wide Simulcast signals are very close in proximity to each other. What happens to the sound quality of an overloaded receiver? It suffers distortion. That's why it's called "simulcast distortion" when actually it's front end overload from powerful EDACS Provoice. The icing on the cake is that Provoice band-pass is wider than analogue OKWIN.

Load up HDSDR or SDR# on the 850mhz spectrum see the clutter and overload. If you have the hardware.

Looking at the waterfall:
The best way I can describe it is Provoice signals look like thick bright lines on the waterfall. Analogue are thinner and have a wavy like form to them. The OKC EDACS system has analogue as well. When they key up their wavy form is well pronounced and still thicker than OKWIN analogue because of signal strength.

Watch the noise floor on an EDACS signal key up along side of a OKWIN analogue signal.The noise floor drops as well as any signal therein next to it, adjacent from it causing imaging. An SDR may not hear the distortion but I can bet an analogue scanner will have distortion. SDR's and analogue radios treat signals different even though they are the same thing. Just processed differently. So I can say safely that as we all know it really is a dog eat dog world in the world of radio.

For Fun try my DSD+ setting for Provoice:

dsd.exe -fp -dr1 -dh1 -O NUL

or

dsd.exe -fp -dr4 -dh8 -O NUL
 
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n5bew1

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OKWIN Motorola Smartzone and OKCPD EDACS Provoice are in the same spectrum of frequency. EDACS is very strong. So strong it can desensitize your front end 'pulling' down on OKWIN weaker signals. I cannot count on my fingers, toes and maybe a few hairs on my head how many times I had to keep re-positioning my antenna while monitoring OKWIN until I cave in and switch Unitrunker to EDACS Provoice.

OKWIN and OKC Core and Wide Simulcast signals are very close in proximity to each other. What happens to the sound quality of an overloaded receiver? It suffers distortion. That's why it's called "simulcast distortion" when actually it's front end overload from powerful EDACS Provoice. The icing on the cake is that Provoice band-pass is wider than analogue OKWIN.

Load up HDSDR or SDR# on the 850mhz spectrum see the clutter and overload. If you have the hardware.

Looking at the waterfall:
The best way I can describe it is Provoice signals look like thick bright lines on the waterfall. Analogue are thinner and have a wavy like form to them. The OKC EDACS system has analogue as well. When they key up their wavy form is well pronounced and still thicker than OKWIN analogue because of signal strength.

Watch the noise floor on an EDACS signal key up along side of a OKWIN analogue signal.The noise floor drops as well as any signal therein next to it, adjacent from it causing imaging. An SDR may not hear the distortion but I can bet an analogue scanner will have distortion. SDR's and analogue radios treat signals different even though they are the same thing. Just processed differently. So I can say safely that as we all know it really is a dog eat dog world in the world of radio.

For Fun try my DSD+ setting for Provoice:

dsd.exe -fp -dr1 -dh1 -O NUL

or

dsd.exe -fp -dr4 -dh8 -O NUL
This seems to confirm what I have experienced with OKWIN in OKC. When I leave Norman say on Western and go north the closer to south OKC I get the more OKWIN's OKC site gets weak and noisy. I have a 10 DB step attenuator in line between the antenna and the scanner. With no attenuation signals around I-240 are weak. If I put 10 DB's of attenuation in line OKWIN's signals get better most of the time. OKC is a RF war zone with cell phone towers and EDACS and all there is a lot of RF floating around. In Norman even driving by within a block of a cell tower will cause Norman's OKWIN site get a little crackly unless I have the attenuation in line. I have a Uniden BC-796D and a 3 inch whip on the car.
 

SCPD

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RF BATTLE

This seems to confirm what I have experienced with OKWIN in OKC. When I leave Norman say on Western and go north the closer to south OKC I get the more OKWIN's OKC site gets weak and noisy. I have a 10 DB step attenuator in line between the antenna and the scanner. With no attenuation signals around I-240 are weak. If I put 10 DB's of attenuation in line OKWIN's signals get better most of the time. OKC is a RF war zone with cell phone towers and EDACS and all there is a lot of RF floating around. In Norman even driving by within a block of a cell tower will cause Norman's OKWIN site get a little crackly unless I have the attenuation in line. I have a Uniden BC-796D and a 3 inch whip on the car.
Yes the best way to try to circumvent adjacent channel front overload is step attenuation.

First image may be what a scanner with a hot front or decent front end sees

Second image is labeled and RF Gain lowered. Still a mess

(I sit 4.5 blocks north east of OKC Comm center!!)

Third image is our goal. I would use that RF Gain value of 23 as 230 in Unitrunker. We want intelligible signals without to much concern for signal strength but of course signal strength matters. If I have clean signals on weaker OKWIN inside a RF battle zone then I win it loses. My dog ate their dog! :)
 

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