roZetta and MR26A

[nobody@xxxxxxxxxxxx (Dave Houston)]

It looks like it will be possible to use the MR26A with roZetta without any
modification to the MR26A. The MR26A draws its power from the PC serial port
DTR & RTS lines and uses the PC TXD line to power its LED. Since it needs to
work with PCs that have 12V on DTR & RTS as well as others that only have
5V, the MR26A has a 3V regulator and operates on 3V. All that's needed is to
supply 5V on either DTR or RTS and this can be done with jumpers internal to
roZetta. Two of the 9600 bps serial ports will have jumpers. The other two
will have solder pads that can be used to supply 5V.

In most cases it will be necessary to improve the MR26A antenna but I've
already published details for that and will publish them again once I get
another web page up for roZetta.

If you want to receive RF codes from X-10 security devices it will be
necessary to replace the PIC in the MR26A or just build another RF receiver
using the generic DIY board I've designed.

The MR25A is 310MHz and cannot realistically be tuned to other frequencies.
The MR26E is 433.92MHz and can *probably* be altered to 418MHz just by
replacing the SAW resonator or by tuning if it is not SAW controlled.

The Pronto TS1000 is getting pretty scarce so, for those who want a
programmable RF remote, I recommend the Pronto TSU-3000 (which has native
support for 418MHz ASK) and building a 418MHz receiver module that can be
used for input to a roZetta serial port. A refurb TSU-3000 can be had for
about $190. You can then program the Pronto to send whatever codes you wish
and program roZetta to do whatever you wish in response to the codes. There
are other (costly) programmable touchscreen remotes. Most of the North
American color versions have 418MHz RF.

Since neither UPB nor the technolgy associated with the 2414S are available
outside of North America there are no plans to ship to Europe or Asia. Due
to Canadian postal policies we will not ship to Canada. We will work with
dealers in areas outside the USA, if any are interested and willing to buy
in some (moderate) quantity.