Pro-433 Picking up cordless phone

Status
Not open for further replies.

hillikus

Member
Joined
Aug 28, 2007
Messages
4
Location
PA
First of all great site with loads of info. Me...well I'm fairly new to scanning on my own, parents always had one and my dad just bought me a PRO-433 from RS. Now I ask you guys if this type of behavior is normal: My PRO-433 is picking up my 5.8GHz G.E. cordless phone. It seems to be picking it up on a few different freqs and it is completely driving my wife crazy. If she had her way I would be getting rid of the scanner just because of this. Now I've been locking out the channels that it is picking it up on but I was under the impression that it would not pick up a cordless phone. Any ideas to help with my dilemma or just keep the channels locked out? The channels it is picking up on were pre-programmed in the scanner from the factory and don't match up with any of my local freqs but it is still troubling me.

The other issue is whether or not to buy a new phone because if my scanner can pick it up then I'd imagine other people could too or would they have to be sitting in my dining room to receive it?

Thanks for your help guys and if you need any more info just let me know.

-Hans
 

Tryton

Member
Joined
Sep 15, 2007
Messages
562
Location
Largo, Fl
what freq is it picking it up at? I also have a GE 5.8, so I want to make sure im not broadcasting as well...
 

rcvmo

Member
Joined
Aug 11, 2004
Messages
433
Location
Romulus, Mi.
It sounds like the heterodyne or in laymen's terms a combination of the scanner's recieved frequency, the scanner's IF frequency, and the cordless phone's frequencies all mixing together and showing up on one of those frequencies you are listening to.
The cordless phone may be throwing a harmonic frequency which can also be picked up by the scanner at certain freq.'s. It may not be as clear, but ledgible. And you probably would have to be somewhere only limited to inside your house to hear it.

rcvmo
 

n2mdk

Member
Joined
Jul 27, 2007
Messages
2,450
Location
Ames, IA
Since those 5.8GHz phones all seem to transmit digitally, I would have to imagine your picking up the the internal frequencies of the phone itself rather than the actual output from it. I would think that proximity is the main reason you can hear it.
 

Russell

Texas DB Admin
Database Admin
Joined
Dec 18, 2002
Messages
1,791
Location
Dallas Texas
Most of the 2GHz and 5.8GHz phones have a "return" or "fallback" frequency in the unlicensed 900mhz band. Very few GHz phones actually use the advertised bands exclusively. Read the fine print, it's in there somewhere.

Russell
 

Radiohead79

Member
Joined
Sep 20, 2007
Messages
9
Location
Twin Cities, Minn.
Russell said:
Most of the 2GHz and 5.8GHz phones have a "return" or "fallback" frequency in the unlicensed 900mhz band. Very few GHz phones actually use the advertised bands exclusively. Read the fine print, it's in there somewhere.

Exactly. Also, a cordless phone uses one freq. for the base and another for the handheld. Surprisingly many 2.4 and 5.8GHz phones use analog 900MHz frequencies for the handheld. The 900MHz portion can be heard on a scanner, so my guess is your '433 is picking up some sort of an image of the 900MHz frequency (assuming your phone is analog and uses the 900 band).

You can look up a phone's freq. range in the FCC database if you're really curious...you just need the FCC ID off the phone. These are near the model and serial # tag.

To your other point, since I got into scanning I promised myself to NEVER own an analog cordless. As you've found out, there is just too much of a risk that someone could hear it. I'd suggest replacing your phone with one that is digital or "digital spread spectrum". If it's not digital there is a strong possibility it can be easily heard on a scanner. Of course for credit card #s, etc. it's always best to use a good ol' corded phone.

I admit that I did own a Uniden 46/49MHz analog cordless beast at one point, but it had a scramble (voice inversion) feature that you could switch on and off!
 

hillikus

Member
Joined
Aug 28, 2007
Messages
4
Location
PA
I'll have to get the freqs when I get home but I'll let you know what they are.
 

mciupa

Member
Moderator
Joined
Nov 5, 2002
Messages
8,349
hillikus said:
I'll have to get the freqs when I get home but I'll let you know what they are.

You are hearing the handset freq. I bet . Check between 924 to 928 mhz. They transmit to the base unit in that range.
 

hillikus

Member
Joined
Aug 28, 2007
Messages
4
Location
PA
mciupa said:
You are hearing the handset freq. I bet . Check between 924 to 928 mhz. They transmit to the base unit in that range.

If I remember correctly the freqs were in the 460-465 mhz range. Ok I called my wife and had her look at the scanner, one of the frequencies was 462.6125. I say one of them because there were more than one and one of the times that the scanner was picking it up I changed the channel on the phone and it stopped. Should have mentioned that in my first post.


Isn't 462.6125 a FRS Freq? Now I'm really not understanding some things.
 
Last edited:

Mick

Member
Joined
Dec 19, 2002
Messages
2,532
Location
Western U.S.
I was at my sister's house and while they used their 5.8 GHz cordless phone I heard both sides of the conversation in the area of 406-410 (I forget the exact frq.) MHz on my scanner. We were all surprised.
 

Russell

Texas DB Admin
Database Admin
Joined
Dec 18, 2002
Messages
1,791
Location
Dallas Texas
I would think for it to show up on that freq it would have to be the sub-harmonic thing. But I still think it's a sub-harmonic of a 900 mhz channel. That is really wierd.

Get a new 'digital spread spectrum' phone. Getting rid of your scanner doesn't prevent others from hearing your wife's phone calls. Analog cordless phones are such easy targets. DSS phones do cost more, but they can't easily be monitored and the sound quality and reliability are much better.

Russell
 
Last edited:

Jimmy252

Member
Premium Subscriber
Joined
Sep 28, 2006
Messages
557
Location
Oakland County, MI
ive scanned the middle 900 MHZ band before and ive heard conversations from people i dont know of, it wasn't a neighbor i knew, so it can be heard for a little ways, but i dont think it can be heard to far from your base.
 

hillikus

Member
Joined
Aug 28, 2007
Messages
4
Location
PA
Update

Well last night I was scanning and it seemed to pick up the phone conversation anytime it would lock on a channel regardless of the channel. Let me explain, while I was testing the phone the scanner locked on my county fire dispatch channel and I could hear the phone conversation AND the dispatcher. Just out of curiosity, while the dispatcher was still talking I locked the scanner onto the police channel and they also happened to be talking and yet again I could hear both their conversation and mine through the scanner. Well just wanted to enlist the help of the experts. Thanks again and I think a DSS phone may be in my future.

-Hans
 

rockag41

Member
Premium Subscriber
Joined
Oct 22, 2003
Messages
130
Location
San Antonio, Texas
I got rid of my home phone altogether. Everyone in my family has a cell phone. The only people that used by home phone wanted to sell me something. Saving about $40.month to go towards the new GRE.
 

kb2vxa

Completely Banned for the Greater Good
Banned
Joined
Mar 22, 2005
Messages
6,100
Location
Point Pleasant Beach, N.J.
Hi Hans and all,

See what you started? Ask a simple question and these guys will analyze it to death while I'll give you a simple answer. Frankly I hate crappy home electronics because pretty much whatever it is radiates spurious signals all over the place and cordless phones are no exception. The solution is simply live with it or live without it, the crappy cordless phone that is. Ask yourself the question "Do I really need this thing?" and act accordingly.

"The other issue is whether or not to buy a new phone because if my scanner can pick it up then I'd imagine other people could too or would they have to be sitting in my dining room to receive it?"

Unless you have a spook in the neighborhood I wouldn't worry about it. If you're really that paranoid just remember a wireless device is a broadcasting station, secrets only remain secrets when you keep your mouth shut.
 

Michael-SATX

Member
Joined
Jan 1, 2005
Messages
910
Location
San Antonio, Texas
I'd say replace that cordless phones with a DSS or DECT 6.0 model. Also, if your Pro-433 is within 90-days ... I would go back to RS and exchange it for AT LEAST a Pro-2055 with alpha-text tags :))
The Pro-433 was just another feature-less flop that seemed to go on clearence as soon as it launched !
Ah heck, some might even consider either the Pro-2096 or Pro-96 models that just recently dropped down to $379 ... or hope for exchange purposes that the Pro-106 "hurries-up" getting to the shelves ?
Say while scanning .. you don't happen to have you Signal Stalker on do you ? I agree it's intermod...
Good luck and Go GRE :))
 

chrismol1

P25 TruCking!
Joined
Mar 15, 2008
Messages
1,181
I'd say replace that cordless phones with a DSS or DECT 6.0 model. Also, if your Pro-433 is within 90-days ... I would go back to RS and exchange it for AT LEAST a Pro-2055 with alpha-text tags :))
The Pro-433 was just another feature-less flop that seemed to go on clearence as soon as it launched !
Ah heck, some might even consider either the Pro-2096 or Pro-96 models that just recently dropped down to $379 ... or hope for exchange purposes that the Pro-106 "hurries-up" getting to the shelves ?
Say while scanning .. you don't happen to have you Signal Stalker on do you ? I agree it's intermod...
Good luck and Go GRE :))

i would say that since this thread is about a year old and the DECT phones came out big earlier this year that he probably has one
 
Status
Not open for further replies.
Top