Re: Suggestions for X10/Automation Widgets

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Jeff Volp" <JeffVolp@xxxxxxx> wrote:

>"Dave Houston" <nobody@xxxxxxxxxxxx> wrote in message
>news:43a9672c.35663098@xxxxxxxxxxxxxxxx
>> "Jeff Volp" <JeffVolp@xxxxxxx> wrote:
>>
>>>The modified CM15A is exactly the framework to implement a security RF
>>>link.
>>>So we may be able to develop something like that in the future.
>>
>> This is difficult unless you institute rolling codes.
>
>I wasn't thinking anything that complicated.  I believe the original poster
>was looking for a system where his "housecode" would be different from
>others on the street.  I do not see a way to do that without modifying the
>receiving modules.  The easy solution is a whole-house blocker.
>
>Another poster commented on stray RF commands from neighbors.  Here is where
>the CM15A can help without getting too complicated.  I'm not suggesting
>security at the level of entry systems.  Just a 2 or 3 code press within a
>time window to enable relaying a received RF command to the powerline.  The
>goal is to prevent neighbors stray commands from controlling his X10
>modules.

Two codes would be sufficient to prevent accidental codes. But, there are
still some difficulties.

The HR12A sends 5-6 copies of a code and each one takes ~105ms so this adds
1/2 second or so delay.

With universal remotes sending to unit codes > 9 is not very
straightforward.

It would be easy to implement with an RF capable programmable remote (e.g.
Pronto TSU3000) but that involves additional hardware to receive 418MHz.