| Author |
Message |
    
Pancake
Junior Member
Username: Pancake
Post Number: 48
Registered: 3-2002
| | Posted on Friday, October 30, 2009 - 7:55 am: | 
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ok i live in a 2 family house (i am on 2nd fl and my landlord is on 1st fl)one night while pulling up to my house in my mobile i scared the landlord right out of bed because when i pulled in the driveway and parked in our parking area out back chatting a little on the air i was interfering with his baby monitor reciever .this landlord is real nice and he just recently bought this house and moved in so i would like to stay on his good side...
my mobile is a galaxy dx55v that has been peaked and tuned with a handheld d104 on it and a fiberglass whip mounted to the fender of the truck ...
since this problem came to be i havent even attempted to use my base at all for fear that the same will happen
my question is is there any way to stop my base from interfering with the baby monitor reciever...common sense tells me that since the baby monitor picks up its signal out of the air with a crappy little antenna and me transmitting is also going into the same airwaves so closeby something tells me that i am out of luck ,however i hope someone here knows something that i dont that could fix the problem
and as far as my base setup i have actually 3 radios inline a cobra 2000gtl stock that i use my silver eagle on,i have a galaxy dx2517 that has been tuned up and i use my tup9 d104 on it ,and i have my small g.e. base(not sure the model) that is stock and i use my turner +2 desk mic on it .also inline is a set of astatic 3 window meters and a drake low pass filter ,the antenna is an antron-99 that is about 7-8 years old its grounded and i run the thick coax .
any help is appreciated |
Tech808
Moderator
Username: Tech808
Post Number: 17189
Registered: 8-2002
| | Posted on Friday, October 30, 2009 - 8:22 am: |
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Pancake,
This may take awhile to Solve / Resolve your problem.
Question #1 ~ Remove all Power Mic's from Radio's and try your Stock Non Modulated mic's and see if you still have the problem and let us know.
Question #2 ~ Are ALL / EVERYTHING ie: your Radio's, Meter's, Speaker's, Coax & Antenna's, Accessories & POWER OUTLET's ALL CONNECTED to a SINGLE POINT GROUND like an 8' Copper Ground rod?
Question #3 ~ Do you share a SINGLE Power Suppy/Fuse/Breaker box with your Landlord?
 Sad to say but if you do then you may never be able to Solve / Resolve your problem.
The Area / Topic below may be of help to you:
Copper Talk
» Ask The Tech
» Installations
» Cb equipment grounding question for Tech 833/others
Lon~Tech808
N9CEF
CEF#808~CVC#002
Radio Enthusiast!
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Bruce
Senior Member
Username: Bruce
Post Number: 5218
Registered: 9-2003
| | Posted on Friday, October 30, 2009 - 5:12 pm: |
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Most are on 49.83 mhz
You might try a low pass filter on your radio ...
See if that cuts it out ...... |
N8fgb
Member
Username: N8fgb
Post Number: 78
Registered: 5-2002
| | Posted on Friday, October 30, 2009 - 8:54 pm: |
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Might be better to see if you can find a unit that operates at 2.4 gig or so. That should solve the problem.49 meg is to close to your first harmonic.
Rich |
Crackshot
Intermediate Member
Username: Crackshot
Post Number: 348
Registered: 10-2005
| | Posted on Friday, October 30, 2009 - 11:16 pm: |
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How much power you running? You might want to reduce the wattage.
The problem with export radios is that they splatter out of band and cause all kinds of problems. |
Tech833
Moderator
Username: Tech833
Post Number: 1768
Registered: 8-2002
| | Posted on Saturday, October 31, 2009 - 10:34 am: |
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I see 2 potential causes here, possibly a third.
First, you need to remember, those baby monitor receivers really suck when it comes to image rejection and adjacent channel rejection. They are almost always simple, single conversion superhets. 49.6 MHz. plus 455 kc. (I.F. frequency) comes out to just above 50 MHz. The second harmonic of your CB band transmissions comes out to around 54 MHz. The monitor receiver could be picking up and demodulating your second harmonic. A lowpass filter on your mobile could help this. You mentioned that your base has a lowpass filter inline already.
Second cause could be that on a poorly designed receiver like a baby monitor, overload would be a concern. The only way to solve this would be for you to buy your landlord a new baby monitor using another frequency band, like 900 MHz. or the 2.4 GHz. models.
The third cause, but admittedly a remote possibility, could be that the baby monitor is also on 27 MHz. and due to afore mentioned poorly designed receiver, is simply picking you up despite being on a different frequency. I recall that my sister had a similar device just after her first son was born. Her and her husband would hear some CBer in the neighborhood on it talking about how lonely he was and laughed their heads off imagining it was their newborn saying it in the other room.
Your first step is to experiment using your base and see if it still happens. If not, get a lowpass filter for your car and stop letting that person adjust your radios for you. Seek out someone to realign your radios using a spectrum analyzer and not just a cheap wattmeter. |
