wierd sounding transmission on 121.500 in the uk

[marty111]

im currently tuned into 121.500 in the uk and am hearing a wierd transmission which is on 24/7 here is the file which i have recorded: http://www.megaupload.com/?d=6EVS1LTH
is 121.500 still used in the uk as a distress frequency or has it been scrapped in the uk?

it sounds like a data transmission but not an ELT which i have ever heard.

 

[davidmc36]

im currently tuned into 121.500 in the uk and am hearing a wierd transmission which is on 24/7 here is the file which i have recorded: http://www.megaupload.com/?d=6EVS1LTH
is 121.500 still used in the uk as a distress frequency or has it been scrapped in the uk?

it sounds like a data transmission but not an ELT which i have ever heard.

Your link just seems to go to the download page for the file sharing service.

This page tells you about the 121.5 switch-over.

http://www.gasco.org.uk/pages/news_item.asp?i_ToolbarID=1&i_PageID=363

 

[marty111]

where file is uploaded

yes thats because i uploaded the audio file to mega upload
so people can download and listen then hopefuly let me know
what the sound means .

 

[Hooligan]

yes thats because i uploaded the audio file to mega upload
so people can download and listen then hopefuly let me know
what the sound means .

What the other guy tried to tell you is that the URL you gave us doesn't show us how to DL the audio file. Clicking on a "download" button just invites us to download some commercial software.

 

[marty111]

ok sorry about the missunderstanding

i have uploaded the file to rapidshre instead here is the link: http://rapidshare.com/files/178126960/121.500.wav.html

 

[davidmc36]

Does it do this constantly or did you just hear it once or twice?

 

[marty111]

its constant

its constant with small silent breaks in between ( when it starts again you can hear a faint beep noise)
i thought it was wierd to be hearing that on the freqency where i am ( im not near any water/airport)

 

[davidmc36]

its constant with small silent breaks in between ( when it starts again you can hear a faint beep noise)
i thought it was wierd to be hearing that on the freqency where i am ( im not near any water/airport)

That is sure a mystery to me. Do you have anything like this in the UK

https://sd.ic.gc.ca/pls/engdoc_anon/sd_pages.main

where you can do a search?

I did notice there was quite a bit of what sounded like background noise of whatever. Is it possible that it is something that is actually on another freq and is close by and strong? Maybe on a birdie or harmonic? How did you find this? By manually tuning in 121.5 or during normal scan?

 

[poltergeisty]

Your first link is fine. People need to learn to enter capchas!

The sound sample might be some kind of phase shift keying which could be a type of teletext. Thought it was ACARS, but that isn't it.

 

[marty111]

i found it by tuning the channel manualy could be on another frequency but dosnt come up
on the close call facility ( so its not near by) i have tried the frequencies near 121.5 but there is nothing on any of those frequencies. I have tried searching google but to no avail.

 

[davidmc36]

Your first link is fine. People need to learn to enter capchas!

The sound sample might be some kind of phase shift keying which could be a type of teletext. Thought it was ACARS, but that isn't it.

There must be some issue with their site then, cause I tried it three or four times last night and nothing, took three times to make it start downloading this time. The second one he used hooked on the first time.

 

[davidmc36]

i found it by tuning the channel manualy could be on another frequency but dosnt come up
on the close call facility ( so its not near by) i have tried the frequencies near 121.5 but there is nothing on any of those frequencies. I have tried searching google but to no avail.

Frequencies nearby 121.5 could give you bleed-over if it is strong, but what about harmonics. The first harmonic of 121.5 is 243.0.

Here is something interesting I just ran across while searching for harmonic info:

http://adsabs.harvard.edu/abs/1989STIN...8924512M

 

[marty111]

i have just brought the frequency up on my dedicated airband scanner and it appears to be quite close
as i have turned the squelch up to 5 and i can still har it ( i am using an external aerial) however on the standard aerial i can not hear the signal wierd eh??

 

[marty111]

having said that i think it is being transmitted intentionally as before the audio starts there is a series of clicks ( like something is keying up for example) its hard to explain could it be that 121.5 has already become dissused in the uk ( it was due to be decommissioned on jan 31st i beleve)

 

[davidmc36]

having said that i think it is being transmitted intentionally as before the audio starts there is a series of clicks ( like something is keying up for example) its hard to explain could it be that 121.5 has already become dissused in the uk ( it was due to be decommissioned on jan 31st i beleve)

I don't know what the plans are there but on this side of the pond I believe it is being retained as what is called a Gaurd Frequency.

 

[marty111]

it would appear to be bleed over as i have just herd traffic control on the freq ( very faintly)
this is very intresting:

Reference: ATSIN 11
Title: Provision of Emergency Frequency 121.500 MHz
Description: This ATSIN describes the current CAA policy on the provision of emergency frequency 121.500 MHz at Air Traffic Control Units.
Status: Withdrawn on 1 January 2004
Review Comment: None
Version:
Date: 22 April 2002
View File: N/A
Purchase Copy: N/A

 

[SCPD]

That is an awesome sound! I love creepy radio sounds.

 

[marty111]

E.t

E.T phone home rofl

 

[kalafoyi]

i live in toledo, oh. i get a data sound on 121.5 and it's 24/7 as well.

 

[davidmc36]

Theory?

Here's a theory. This document:

http://www.fcc.gov/Bureaus/Cable/Notices/2000/fcc00273.doc

is about a cable company in Detroit being fined for excess signal leakage causing interference on 121.5.

Do current cable companies operate in the 54-216 mhz range talked about in this document?