InterceptRadio.com Forums

As you can see above, they are clearly not. Sorry, I am probably using the wrong wording. I think these guys are using 6.25khz not the full 12.5khz bandwidth. Why I don't know. I guess their radios could be using the 2.5khz deviation on Tx.

Here's 155.58 currently:

Nobody is running analog on 6.25. Trust me. I believe the only radios that will do 6.25 will only do it in digital.

Step size is not bandwidth. Trbowest uses 6.25 steps at 12.5khz on part 22 freqs.

Analog bandwidth is variable. WSP is the only one I know (over here) that ever bounced all the way to 5khz.

Many agencies in WA got extensions at very close to the last minute.

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

I understand what you are saying. All I know is what I can see on the SDR. Perhaps they have some kind of filtering done on the output signal but *something* is clearly limiting their bandwidth to 6.25khz.

Here's my proof:

If its Kitsap (north), Im watching the needle on my 1200 super S swing to just at 3khz deviation. Maybe a config issue with the graphs there?

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Looks like Thurston county 911 is running 6.25 in VHF FM on 155.550. That is confirmed by my SDR testing as well.

http://wireless2.fcc.gov/UlsApp/UlsSear ... q=16889918

You need to calibrate that thing man! :mrgreen:

What are you seeing at 154.665?

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Does this match with what you're seeing?

PS. Can you post pics of your service monitor screenshots? That would be helpful.

Here is 154.665:

Here's 155.55. It sure looks like 6.25khz to me...

For reference, here's 162.55 Mhz:

Ill post one from KCSO south (12.5kc) when I catch it for comparison.

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Okay thanks. I had to go do some reading. I think I finally got a grasp on this...

FWIW, this is a very good explanation: http://www.ycars.org/EFRA/Module%20B/fmapps.htm

Ahhh. Thanks!

Its funny that most of my retired counterparts remind me that we have been narrowband since the 60's. :D (the last time this industry went through this.)

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Yes, it's funny how FM is so very different than AM signals. :?

The promised narrow banded KCSO channel for anyone that was waiting. :mrgreen:

Both pictures were taken at basically peak audio.

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."