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- From: ornitz@kodak.kodak.com (Barry Ornitz)
- Newsgroups: sci.electronics
- Subject: Re: Restrictions on 46/49MHz band?
- Summary: FCC Rules Part 15
- Keywords: Part 15, Title 47 CFR, unlicensed transmitters, cordless telephones
- Message-ID: <1992Nov7.011652.6443@kodak.kodak.com>
- Date: 7 Nov 92 01:16:52 GMT
- Article-I.D.: kodak.1992Nov7.011652.6443
- References: <1992Nov5.123811.11033@doug.cae.wisc.edu>
- Sender: Barry L. Ornitz
- Followup-To: sci.electronics
- Distribution: usa
- Organization: Eastman Chemical Company
- Lines: 39
-
- In article <1992Nov5.123811.11033@doug.cae.wisc.edu> kolstad@cae.wisc.edu
- (Joel Kolstad) writes:
- >I'm just curious... does anyone out there know the bandwidth limitations
- >on the baby monitor/cordless phone/RC car/etc. non-lincensed 46 and 49MHz
- >radio bands?
-
- To start with baby monitors must operate between 49.82 and 49.90 MHz. Cordless
- telephones operate in the 46.60 to 46.98 and 49.66 to 50.0 MHz bands on 10
- assigned channels (actually 10 base transmitter channels at 46 MHz and 10
- handset channels at 49 MHz).
-
- >I believe I've heard that the power output is limited to producing an
- >E-field of 10000uV/m at a distance of one meter from the transmitting
- >antennta (correct me if I'm wrong). But what is the frequency range
- >of the "49MHz band?" I would assume that I can't start modulating my
- >49MHz carrier at 1Mhz, for instance... :-)
-
- Actually the limits are 10,000 uV/m measured at 3 meters. The detailed rules
- are somewhat complicated as to emission bandwidths but basically all of the
- energy in the carrier and modulation products must fall within 49.82 to 49.90
- MHz band with emissions outside this band being severely limited. This
- effectively limits your modulation frequencies to 4 kHz or less if you stay
- in the center of the band.
-
- The full set of rules can be found in Part 15 of the FCC Rules and Regulations.
- Check your local library for the Code of Federal Regulations, Title 47, for
- a copy. There are special provisions for home-built (but not marketed)
- devices for this band that are outlined in Part 15.
-
- Barry
- -----------------
- | ___ ________ | Dr. Barry L. Ornitz WA4VZQ
- | | / / | | Eastman Kodak Company
- | | / / | | Eastman Chemical Company Research Laboratories
- | |< < K O D A K| | Process Instrumentation Research Laboratory
- | | \ \ | | P. O. Box 1972, Building 167B
- | |__\ \________| | Kingsport, TN 37662 615/229-4904
- | | INTERNET: ornitz@kodak.com
- -----------------
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