Re: CM11A hangup: Any better products?

[Joerg <notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx>]

Hello Dave,

> It is ABSOLUTELY so! All of the X-10 made PLC transmitters for which I've
> seen schematics (and looked at their innards) with the exception of the most
> recent RR501 (last 7-8 years?) use an LC controlled transistor oscillator.
> You can see the circuit in the schematics for the TW523, CM11A, CM15A,
> TM751, mini & maxi controllers. etc. If you need URLs, I can supply them.

Yes, do you have the URL for your version of the CM11A?

> PLC transmitters made by SmartHome and other manufacturers may use
> resonators and generate the PLC carrier with a PIC - I haven't seen many
> schematics for them.
>
> The most recent RR501 does generate the 120kHz with the PIC _BUT_ the PIC
> itself uses an LC circuit instead of a crystal or resonator on its OSC pins
> so it's unlikely to be any more tightly controlled than the others.

IIRC mine has a fixed resonator. A tunable LC would be more expensive in
production.

> The same is true for all of the wireless devices.

I know. Those are a pain, hardly adjustable. I found some of the key
chain ones all over the map so we quit using them.

Regards, Joerg

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