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View Full Version : Hitec Reciever -Narrow Band means ?


woody
12-01-2005, 07:46 PM
I have a Hitec Reciever HFS-05MS
On the box it states
1 Narrow Band
2 Auto Gain Control
Can anyone explain in more detail what they mean

Thanks
Woody

rcers
12-01-2005, 08:08 PM
Narrow band is the term for post 1991 radio systems, as our channel bandwidth allocation was decrease then. Everything sold today on 72MHz is.

Now in the UK and 35MHz I'm not too sure!

Mike

Matt Kirsch
12-02-2005, 03:56 PM
FM stands for frequency modulation, meaning the signals from transmitter to receiver are encoded by modulating, or changing, the frequency of the radio waves being sent (the radio's channel is just the base frequency). This requires a band, or range, of radio frequencies.

Back in the old days, the technology of the time presumably required much wider variations in frequency to get a reliable signal than we do today. This is where we get "wide band" versus "narrow band."

Narrow band has been around for at least 20 years, and has been a matter of law in the USA since 1991 (we're required to use narrow band transmitters and receivers now because are channels are spaced too closely). Really, the term "narrow band" doesn't mean much these days, as ALL radio equipment is now narrow band. It's just there to look impressive to those who don't know what it means. It's marketing.

Auto gain control is another one of those marketing terms. I believe it just means that the receiver automatically tunes into the signal... Well, every receiver does that.

hoppy
12-02-2005, 07:09 PM
Automatic gain control (AGC) is the circuitry inside a radio receiver that automatically increases or decreases the gain of the various stages of a receiver so that, no matter how the received signal fluctuates, the output remains more or less constant.

Lots about that Rx on google - http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2003-43,GGLD:en&q=HFS%2D05MS