my wierd rf thing (was: [Noisebridge-discuss] Science, engineering and design huddle opening subject, RF Phone kind of thing)

[d p chang]

Michael Kan Kan <michaelkan_kan at yahoo.com> writes:

>  Why do stuff the hard and expensive way?

hmmm... i thought of it more as experimenting by modifying bits in ways
that i thought i could do. clearly, i'm out of my depth though.

>  One can do better and cheaper with a gain antenna than anhy kind of active
> circuit.
>  Simply upping the power does little good when it comes to reception
> of signals.

i'm actually generating the signal myself and then amplifying that to
transmit. pre-amp-stage i have some other goo that takes a binary stream
and generates a gsm modulation rf signal (at least by my reading and if
i squint and look at it sideways on the spectrum analyzer :-).

now, rather than wiring straight to the antenna of a phone i thought i'd
play w/ actually taking that signal and bumping it enough to send across
the room. maybe the antenna isn't right as well (i got out of a bin at
hsc), but the amp stage is eating more power than i expected. this is
because i only vaguely rememeber some old class materials so i figured
i'd try to kibitz w/ people who know more than me.

>  20 USD is very cheap so why not purchase one for everyone at
>  Noisebridge?

well, if everyone needed/wanted a vco chip i think i'd have enough for
the next ordering tier. the rest of the support bits are somewhat
annoyingly fiddly, but people would learn surface mount soldering in the
process :-)

\p
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