Can you pick up 2.4 ghz cordless phones on a scanner?

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KR4BD

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I don't think there are any commercially available scanners covering 2.4 GHZ and if there were, you would probably have to deal with digital transmissions and possible encryption.
 

mciupa

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You can hear the handset to base on some models .

Why do I feel I am abetting a stalker ?
 

kikito

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NOTE: Didn't mean to "hijack" this thread but since the OP removed his post, I thought it would be a good time to raise awareness about this subject


This is a good question to bring up, mainly to raise awareness that there's so many phones out there advertised as digital operating in the 2.4GHz and even 5.8GHz band but you can still pick them up in the lower bands in analog.

I recently was near a brand new Uniden 5.8GHz phone that suddenly started coming through in analog around 921MHz on my scanner. I looked in the manual and nowhere in there it says it's even digital or that it strictly operates in the 5.8 GHz band only.

So for those that don't know, make sure the phone you buy uses some sort of digital Spread Spectrum technology i.e. DSSS or FHSS, otherwise it's likely that it's dual or even triple bander using analog (and different bands) in one direction or the other.

The latest technology now is those 1.9GHz DECT 6.0 phones. Supposedly they're better in that they operate in a less crowded band and use pure digital and even heard it uses encryption but I haven't research it yet to know for sure.

EDIT: Here's some more info about DECT: http://www.dect.org/content.aspx?id=18

It seems that it does in fact uses encryption and TDMA. It uses frequencies between the 1921-1929MHz range.

EDIT: Here's some more info from Wikipedia about DECT: http://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunications

It says the encryption used is "weak" but I would think something is better than nothing and it might be more work than its worth in most cases to try and "hack" the algorithm......

Here's an excerpt:

" [DECT] provides encryption services with the DECT Standard Cipher (DSC). The encryption is fairly weak, using a 35-bit initialization vector and encrypting the voice stream with 64-bit encryption."


EDIT: Here's another source actually stating that DECT encryption is in fact "very secure":

http://uswww03.gnnetcom.com/public/US/9300Site/pdf/DECTWT-002 0506.pdf
 
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gewecke

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Believe it or not this is common!
I have a brand new GE model# 2785 2.4ghz. phone and from research
I found that the base unit transmits on 2.4ghz. but the handset does indeed transmit on 900mhz.!
Spread spectrum seems to be the only way to be sure,for sure!
N9ZAS.
 

Jose_Pointero

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Yeah, I got a surprise the other day regarding this. I brought my handheld with me to a buddies apartment on the 2nd floor in a house. As soon as I walked in I picked up a phone conversation and was curious about it, because it was on a lower freq nowhere near 900 or anything. We listened for a bit and he said "holy crap, that's the people downstairs!". He said he had been down there before and their phones are "new". Pretty weird that I would be able to hear them on such a low freq like that.
 

b7spectra

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If the phone is partially in analog and you have a scanner with Close Call technology, just get your scanner near it and away you go!
 

ampulman

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Sitting at my computer, monitoring my collection of Federal freqs as I usually do, my scanner stopped on one of my programmed frequencies (150 - 170 mhz range), and I was surprised to hear an 'operator' speaking, immediately followed by music (on hold).

Shortly afterward, the operator came back on, followed by my wife's voice. I was shocked, as she was talking on a 900 mhz unit, which outputs an unintelligible audio in the 900 band. Both sides of conversation were audible.

I guess I need to think about a new phone.

Amp
 

joneil2000

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I'm interested in this question from the other point of view - which cordless phone(as they all seem to be cordless anymore) can NOT be scanned for sure? Is there such a thing?
 

East_Algoma

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dect 6

The TDMA Freq for DECT is 1920 - 1930

search this article out on Google :

Sniffing DECT Wireless Devices
By
Larry Pesce

There is DECT 6.0 sniffers n listeners



NOTE: Didn't mean to "hijack" this thread but since the OP removed his post, I thought it would be a good time to raise awareness about this subject


This is a good question to bring up, mainly to raise awareness that there's so many phones out there advertised as digital operating in the 2.4GHz and even 5.8GHz band but you can still pick them up in the lower bands in analog.

I recently was near a brand new Uniden 5.8GHz phone that suddenly started coming through in analog around 921MHz on my scanner. I looked in the manual and nowhere in there it says it's even digital or that it strictly operates in the 5.8 GHz band only.

So for those that don't know, make sure the phone you buy uses some sort of digital Spread Spectrum technology i.e. DSSS or FHSS, otherwise it's likely that it's dual or even triple bander using analog (and different bands) in one direction or the other.

The latest technology now is those 1.9GHz DECT 6.0 phones. Supposedly they're better in that they operate in a less crowded band and use pure digital and even heard it uses encryption but I haven't research it yet to know for sure.

EDIT: Here's some more info about DECT: http://www.dect.org/content.aspx?id=18

It seems that it does in fact uses encryption and TDMA. It uses frequencies between the 1921-1929MHz range.

EDIT: Here's some more info from Wikipedia about DECT: Digital Enhanced Cordless Telecommunications - Wikipedia, the free encyclopedia

It says the encryption used is "weak" but I would think something is better than nothing and it might be more work than its worth in most cases to try and "hack" the algorithm......

Here's an excerpt:

" [DECT] provides encryption services with the DECT Standard Cipher (DSC). The encryption is fairly weak, using a 35-bit initialization vector and encrypting the voice stream with 64-bit encryption."


EDIT: Here's another source actually stating that DECT encryption is in fact "very secure":

Page not found..
 

AD8NT

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The latest technology now is those 1.9GHz DECT 6.0 phones. Supposedly they're better in that they operate in a less crowded band and use pure digital and even heard it uses encryption but I haven't research it yet to know for sure.

EDIT: Here's some more info about DECT: http://www.dect.org/content.aspx?id=18

It seems that it does in fact uses encryption and TDMA. It uses frequencies between the 1921-1929MHz range.

EDIT: Here's some more info from Wikipedia about DECT: http://en.wikipedia.org/wiki/Digital_Enhanced_Cordless_Telecommunications

It says the encryption used is "weak" but I would think something is better than nothing and it might be more work than its worth in most cases to try and "hack" the algorithm......

Here's an excerpt:

" [DECT] provides encryption services with the DECT Standard Cipher (DSC). The encryption is fairly weak, using a 35-bit initialization vector and encrypting the voice stream with 64-bit encryption."


EDIT: Here's another source actually stating that DECT encryption is in fact "very secure":

Page not found. Can we help?



DECT usually doesn't even use encryption for both directions unfortunately.
https://www.youtube.com/watch?v=omS7OMLAnaA

Soon enough a simple SDR will be able to grab these, in the meantime there is the DeDECTed project.
 

SCPD

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The law says to intercept phones is illegal however it does not stop it from happening. There is receivers and a couple foreign made scanners that can receive some cordless modern phones. Do people try to import yes. Do some get caught yes but not all. Some newer cordless phones do use secure (I'll use that loosely) technology but even then if a receiver or scanner mixed with software it can be done. Is it legal? No. But some do it illegally. I'll say I don't condone it and one shouldn't try it. But facts are facts. If your really worried about 1 person out of entire area only capable of it there is higher end phone systems to prevent that but probably wouldn't be cost effective for a basic low end home user. If your that worried of a wireless intruder the old corded phone in closet has a use for your end at least but not from the wireless ends.
 
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