Author Topic: Transmitter Loading  (Read 2291 times)

Jeff

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Transmitter Loading
« on: March 17, 2014, 09:20:18 AM »
One of my customers reported that when he plugged a second PSC01 transmitter into a circuit, the reliability of his system degraded.  I just measured the output of a Maxi Controller dropped from 8.16Vpp to 5.60Vpp when a TW523 was plugged into the same power strip.  Interestingly, the drop was only to 7.68Vpp when the XTB-523 was plugged into the strip instead of the X10 module, which indicates the XTB output stage presents a far lighter load to incoming X10 signals.

Jeff
X10 automation since the BSR days...

Brian H

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Re: Transmitter Loading
« Reply #1 on: March 19, 2014, 03:34:40 AM »
Thank you for the heads up on the loading.
I have some older 2000 series Smarthome one way X10 clones.
They also seem to load the power line signals some what.
No tuned receive coil. Just a series capacitor inductor network into the microcontroller and a pair of clipping diodes.

Jeff

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Re: Transmitter Loading
« Reply #2 on: March 19, 2014, 06:42:49 AM »
I have some older 2000 series Smarthome one way X10 clones.
They also seem to load the power line signals some what.

Passive input stages will absorb some signal, and even more if the input stage includes clamping diodes for overload and transient protection.  Most XTB input stages look like about 3K under 1.4Vpp, and 130 ohms to signals above 1.4Vpp due to the clamping diodes.

Jeff

X10 automation since the BSR days...

 

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