On 25/11/2010 11:08, William "Chops" Westfield wrote:
> On Nov 24, 2010, at 9:34 PM, Vitaliy wrote:
>
>> I shall assume that a
>> 9600 baud pure-FSK modem IC does not exist. :)
> Don't some of the low cost wireless transceivers claim to do 9600bps
> FSK ?
>
ASK/OOK on 433MHz and other ISM bands up to 9,600 using Manchester=20
Encoding is feasible. The chips have no modem as such. The RX is a=20
superhet and dataslicer.

Analog Devices and Maxim have some parts that carry FSK 9,600. But it's=20
just the RF part to /from baseband (i.e. Superhet receiver). Not the=20
actual "modem".

There are a couple of modules that have modem too..

http://in.rsdelivers.com/product/micrel/micrf620z-tr/433mhz-ism-band-transc=
eiver-module/0382652.aspx

I have something like this that does 9,600 or maybe 19,200 full duplex=20
maybe Micrel?
There is no baseband. UHF only.. may not really be FSK, but QAM / QPSK

The chips these are based on are often adaptable for 350MHz to 950MHz,=20
but no other frequency.

> Doing it in 20k of bandwidth seems like it would be pretty tricky,
> though.
> On phones we got 1/5th of supposed total bandwidths (600bps out of
> 3000Hz
> bandwidth?)
>
> BillW
>

--=20
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