Re: CM11A hangup: Any better products?

[nobody@xxxxxxxxxxxx (Dave Houston)]

George Pontis <gpontis@xxxxxxxxxxx> wrote:

>> I've looked at the frequency of several X-10 transmitters and found all to
>> be at 120kHz.
>
>The transmit frequency is controlled by the crystal or resonator, which is usually
>quite accurate. The transformer (X2 in the powerlinc circuit) is part of a tuned
>circuit that may not be perfectly tuned to 120KHz. If not, then the receive signal
>coupled through C5 will be smaller at 120Khz. Transmit operation is not affected
>very much by a small mistuning; the transmit current will increase and that is
>about all.

None of the X-10 modules used in North America use crystals or resonators -
all are LC tuned. This is true both for the 120kHz PLC modules as well as
for their 310MHz and 418MHz wireless devices.

Transmitter mistuning is much more of a problem than receiver mistuning as
it will affect all receivers whereas a mistuned receiver has no effect on
others.

The 1132 circuitry designed by SmartHome is not at all similar to the PLC
design used by X-10. I gave a link to a schematic for an X-10 made lamp
module.