Re: X10 Transmit Buffer

[nobody@xxxxxxxxxxxx (Dave Houston)]

nobody@xxxxxxxxxxxx (Dave Houston) wrote:

>"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote:
>
>>AFAIK (and that ain't much!) the CM11A, besides having lower output voltage
>>than most controllers, also suffers from a peculiar output voltage decay
>>during the signal transmission itself.  I would assume since you're able to
>>boost the signal to a uniform output level despite varying input voltages
>>that the XTB X-10 signal will not contain the original transmitter's
>>waveform flaws.  I just wanted to be sure a CM11A plugged into the XTB
>>device would NOT show the same voltage drop during its output burst.
>
>The CM11A fade problem is easily cured by changing one resistor. If you
>search CHA for "CM11A schematic John Galvin" and read the entire thread
>you'll find where John recommended two possible fixes. I've changed the
>resistor on one of my CM11As and can confirm that it now has a steady
>output. It's still just over half of that from other X-10 PLC transmitters
>but the fade is gone.
>
>Doing that and then using Jeff's booster should really help with the CM11A.

The specific thread is...

http://groups.google.com/group/comp.home.automation/msg/683aab3fb0577048?q=elk-esm1+schematic&hl=en&lr=&ie=UTF-8&oe=UTF-8&rnum=2

Changing R12, per John's recommendation, is a fix.