154.265

Discussion forum for scanning Eastern Massachusetts, including Norfolk, Suffolk, Middlesex, and Essex counties, as well as the greater Boston metropolitan area.
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garys
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154.265

Post by garys »

I never got around to deleting the old Hingham FD VHF frequency from my scanners. Yesterday, I was driving on i-93 through Quincy and heard activity on this frequency. The audio sounded like voice inversion scrambling, but the PL was 203.5.

The Hingham license is still active according to the FCC database, but I don't know why they would be using a scrambled signal.

There are actually a lot of still active licenses, but I don't see any of LE.
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ecps92
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Re: 154.265

Post by ecps92 »

first instinct is an image, since I have them still in the radio but have not heard anything, except 6.25 away users splashing

Wasn't there a similar thread [not sure on the Inversion] but someone indicating similar use on 154.2950 203.5 within the past year or two ?
garys wrote:
04 Mar 2020 12:40
I never got around to deleting the old Hingham FD VHF frequency from my scanners. Yesterday, I was driving on i-93 through Quincy and heard activity on this frequency. The audio sounded like voice inversion scrambling, but the PL was 203.5.

The Hingham license is still active according to the FCC database, but I don't know why they would be using a scrambled signal.

There are actually a lot of still active licenses, but I don't see any of LE.
Bill Dunn N1KUG
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http://scanmaritime.com

"The tougher it is to find a frequency, the more it makes me want to work to find it. - I've learned to use the SEARCH Button"

garys
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Re: 154.265

Post by garys »

I would be inclined to think it was an image except for exact match of the PL and the clarity of the audio.

It might have to remain a mystery since there are not audio clues to help ID who it is.

Of course, the simple solution is to just remove it from my scanner. ;)
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ecps92
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Re: 154.265

Post by ecps92 »

PL is generally the same for an image.
Go back to the days of 504.xxxxx to get rid of images to Boston Fire and Quincy Fire.

DPL is sometimes a different matter, but PL has generally never changed.
garys wrote:
04 Mar 2020 18:53
I would be inclined to think it was an image except for exact match of the PL and the clarity of the audio.

It might have to remain a mystery since there are not audio clues to help ID who it is.

Of course, the simple solution is to just remove it from my scanner. ;)
Bill Dunn N1KUG
Cruise Ship Frequencies
http://scanmaritime.com

"The tougher it is to find a frequency, the more it makes me want to work to find it. - I've learned to use the SEARCH Button"

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W1KNE
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Re: 154.265

Post by W1KNE »

garys wrote:
04 Mar 2020 18:53
I would be inclined to think it was an image except for exact match of the PL and the clarity of the audio.

It might have to remain a mystery since there are not audio clues to help ID who it is.

Of course, the simple solution is to just remove it from my scanner. ;)
What fun is in that removing it from your scanner? Never know when something new comes on!

Also I agree with the clarify of audio thing. "Images" typically sound off frequency (because they normally are... an image of 150.0 will actually be at 154.260 {fake sample} but the scanner's IF is wide enough to decode it.)
Because the PL tones are pilot tones (and audible) and not RF, they won't shift on an image. Voice doesn't go higher or lower on that. So there won't be a change in PL on an image, ever. Now, what can happen is, other noise in the frequency, even if offset, can cause the scanner to falsely read it as another tone, but the actual PL will remain where it is.
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garys
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Re: 154.265

Post by garys »

At some point, it becomes over crowded with little or no use frequencies. I don't know exactly where that point is because I still have QPD Channel 3 (453.275) programmed into my scanners although I think I hear traffic once every five years or so. ;)

The PL tone info is interesting.

W1KNE wrote:
05 Mar 2020 09:58
What fun is in that removing it from your scanner? Never know when something new comes on!

Also I agree with the clarify of audio thing. "Images" typically sound off frequency (because they normally are... an image of 150.0 will actually be at 154.260 {fake sample} but the scanner's IF is wide enough to decode it.)
Because the PL tones are pilot tones (and audible) and not RF, they won't shift on an image. Voice doesn't go higher or lower on that. So there won't be a change in PL on an image, ever. Now, what can happen is, other noise in the frequency, even if offset, can cause the scanner to falsely read it as another tone, but the actual PL will remain where it is.
We're peace loving people, we're not hunting trouble, but if trouble should find us, we'll stand up and fight.

cdgordon
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Re: 154.265

Post by cdgordon »

With the newer scanners, if I have unknowns or old channels, I add an alert tone to get my attention if they ever get reused.

chris

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W1KNE
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Re: 154.265

Post by W1KNE »

Oh and to the original post,

154.2650 203.5 is the correct frequency and tone. What was ID'ed is correct, they are using encrypted communications.

The user won't be discussed here, however, per our TOS.
Mike Fitzpatrick
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Issues with Scan New England can be privately addressed to me. W1KNE at scan-ne.com.

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W1KNE
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Re: 154.265

Post by W1KNE »

cdgordon wrote:
05 Mar 2020 11:46
With the newer scanners, if I have unknowns or old channels, I add an alert tone to get my attention if they ever get reused.

chris
I did that with Putnam, CT's VHF repeater. After several trips through that area but never hearing any comms, I originally did that, while running in open PL tone.
(Which was annoying to a degree, because of how well Harvard PD with a 107.2 PL comes in down in Putnam.) Until I finally heard them.
Since then, they've had a significant uptick in radio traffic.
Mike Fitzpatrick
Broadcast Engineer - RF Enthusiast
Owner: Scan New England - NECRAT.US
Issues with Scan New England can be privately addressed to me. W1KNE at scan-ne.com.

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