We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.

Author Topic: 49.847 mHz Baby monitor?  (Read 5819 times)

Offline flexoman61

  • DXing Phenomena
  • *******
  • Posts: 3027
  • Connecticut, USA
    • View Profile
    • Email
49.847 mHz Baby monitor?
« on: April 13, 2017, 1917 UTC »
Picking up a signal on 49.847 MHz, sounds like someone's baby monitor.
I tuned past it, don't want to spy on people, but do these monitors operate around this frequency?
Please QSL to: flexoman61@gmail.com
Connecticut
ICOM R75, Kenwood R-2000, Radio Shack PRO-2037
43m band folded dipole/VHF ground plane

Offline ChrisSmolinski

  • Administrator
  • Marconi Class DXer
  • *****
  • Posts: 31106
  • Westminster, MD USA
    • View Profile
    • Black Cat Systems
Re: 49.847 mHz Baby monitor?
« Reply #1 on: April 13, 2017, 2025 UTC »
Yes, the older ones used that range as did cordless phones, the newer models are around 900 MHz I think.  I don't know if newer models are still analog or digital.
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 400 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree

Offline fpeconsultant

  • DX Legend
  • ******
  • Posts: 1270
  • I miss "Up Against the Wall Radio"...
    • View Profile
    • Email
Re: 49.847 mHz Baby monitor?
« Reply #2 on: April 14, 2017, 0029 UTC »
Yes I used to hear nearby baby monitors in the same 49mhz range - quick to turn the dial too. 
Near Chicago, IL USA.  Drake R8, Ten-Tec RX340, JRC NRD545, Watkins Johnson HF-1000, Wellbrook loop at 28', 43m inverted vee.  Please QSL to fpeconsultant@aol.com thanks.

Offline flexoman61

  • DXing Phenomena
  • *******
  • Posts: 3027
  • Connecticut, USA
    • View Profile
    • Email
Re: 49.847 mHz Baby monitor?
« Reply #3 on: April 14, 2017, 0058 UTC »
Thanks for the info. We used those things for years when our kids were small.

Please QSL to: flexoman61@gmail.com
Connecticut
ICOM R75, Kenwood R-2000, Radio Shack PRO-2037
43m band folded dipole/VHF ground plane

Offline ThaDood

  • DX Legend
  • ******
  • Posts: 1209
  • Likely, not where you are.
    • View Profile
    • Extreme Part #15!
    • Email
Re: 49.847 mHz Baby monitor? Yep...
« Reply #4 on: April 17, 2017, 0944 UTC »
        They still sell 49MHz FM baby monitors, and with two channels. CH1 = 49.870MHz, and CH2 = 49.850MHz. Ya got a good 6M, or a decent scanner, antenna and you can hear those sucka's a couple of miles easily.
I was asked, yet another weird question, of how I would like to be buried, when I finally bite the big one. The answer was actually pretty easy. Face-down, like a certain historical figure in the late 1980's, (I will not mention who, but some of you will get it, and that's enough.) Why??? It would be a burial that will satisfy everyone: (1) My enemies will say that it will show me where to go. (2) On the same point, I can have my enemies kiss my butt. (3) It will temporarily give someone a place to park a bicycle. See??? A WIN / WIN for everyone.

Offline R4002

  • DXing Phenomena
  • *******
  • Posts: 2984
    • View Profile
    • R4002 - YouTube Videos
Re: 49.847 mHz Baby monitor?
« Reply #5 on: April 21, 2017, 0447 UTC »
I used to have a neighbor with an older-generation 10-channel 46/49 MHz cordless phone with the base station (which had a telescopic whip antenna) located on the top floor of their 3-story home.  The cordless phone base station in question got out several miles and the neighbor talked on the phone a lot.  

The 49 MHz band is still used even though most baby monitors have moved up to the various ISM bands 900MHz/2.4GHz/5.8GHz (and various combinations of digital/video/spread spectrum).  The same can be said for cordless phones (plus the 1.9GHz DECT band).  However, cheaper cordless phones still use analog 900 MHz band (902-928 MHz) for base-to-handset link transmissions, often using random frequency steps (there appears to be no standardization in regards to this, with some companies using 12.5 kHz channel steps, others using 40 kHz channel steps, etc).  

RadioShack used to sell 49MHz walkie-talkies (the TRC-512 model among others) before they switched to selling FRS radios.  The 5 channels used by these radios were also the channels used by baby monitors (and cordless phone handsets!).  Made for interesting situations when a neighborhood had baby monitors, cordless phones, and kids with 49MHz FM walkie talkies all on the same frequency.  Further complicating things is the fact that 49.600-50.000 MHz is technically a US military band, and US Army helicopters have been monitored on 49.700 MHz, 49.750 MHz and 49.950 MHz.  

49.830 MHz
49.845 MHz (some companies use/used 49.850 MHz instead)
49.860 MHz
49.875 MHz (some companies use/used 49.870 MHz instead)
49.890 MHz

« Last Edit: April 21, 2017, 0453 UTC by R4002 »
U.S. East Coast, various HF/VHF/UHF radios/transceivers/scanners/receivers - land mobile system operator - focus on VHF/UHF and 11m