Re: TI-H: RF Link Idea....
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So you're sayind i'd need a modem of sort, then connect that to an RF
transmitter/receiver? Uhg, that's lots of work. I wanted to use a walkie
talkie, and it uses a mic, which converts sound into electrical pulses. Why
wouldn't the electrical binary code from the calc simply represent a sound
wave? A mic pics up sound, then converts it into electricity, then sends it
over RF. Why can't plugging the send cable into the mic spot just work? I
get what you're saying about it needing binary, but like you said, its +5v,
0v. On, off. Why doesn't that end up being represented as a sound wave?
Binary: Analog:
__|__||_|| _/\__/\/\_/\/\
It should work! I don't get why it cant!
/--------------------------------\
/ Travis Pettijohn \
/ primary: travisp@inil.com \
/ alternate: travisp@juno.com \
/ http://www.inil.com/users/travisp/ \
/------------------------------------------\
----------
> From: Greg Hill <ghill@lab.tech.bhs.davis.k12.ut.us>
> To: ti-hardware@lists.ticalc.org
> Subject: Re: TI-H: RF Link Idea....
> Date: Saturday, November 02, 1996 12:44 AM
>
> travisp wrote:
> >
> > TTL?
>
> Yeah. It's a TLA (three-letter acronym). It means transistor-transistor
> logic. It's how computers work. The logic signals (high and low)
> correspond to voltages, typically +5v and 0v. Those are the digital
> signals that get piped around computers, representing whatever
> information you're processing. TTL basically says that a HIGH signal
> equals +5v and a LOW signal equals 0v (or *very* close to it). You'd
> need a chip (modulator) that converts this digital signal into an analog
> (sound) signal for transmission over the radio, and then a demodulator
> chip to convert the analog/sound signal back into TTL logic signals.
> Whew!
>
> --
> Greg Hill
> http://braves.bhs.davis.k12.ut.us/
> ghill@lab.tech.bhs.davis.k12.ut.us
> greg_hill@email.state.ut.us
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