All house code receiver is the reason I bought CM15A, but it didn't
respond to any RF signal sent from any remote recently. It was once
working for a while. I used other receiver like TM751, it just works
fine. by using the active home pro software, it can send the X10
command to the power line. Any clues I can fix this problem by not
sending it back to X10.com?

What is the distance between the remote and the CM15A? My initial tests
showed limited RF range of 20-25 feet. I replaced the antenna with one that
is remotely located, more efficient, and preamplified. Of course, this voids
the warranty.

Have you checked the "transceived housecodes" setting? My CM15A recently
stopped sending X-10 PLC commands in response to RF. I feared I had blown
one of the controller pins (My controller has been moved to a breadboard so
I can experiment.) but it turned out that I had inadvertently cleared the
"transceived housecodes" settings.

tony_9221@yahoo.com (Tony_king) wrote:

>All house code receiver is the reason I bought CM15A, but it didn't
>respond to any RF signal sent from any remote recently. It was once
>working for a while. I used other receiver like TM751, it just works
>fine. by using the active home pro software, it can send the X10
>command to the power line. Any clues I can fix this problem by not
>sending it back to X10.com?

Hi Dave,
My remote is just several inches near the CM15A, so not a distance
problem. I also double checked the transeiver house codes, all are
selected. But CM15A still can't react to any RF signals. I wonder if I
can use the multimeter to check the RF receiver daughter board in the
CM15A to see if it really receives the signal. Can you give me some
hints of how to do this?

Thanks!

Tony

Tony,

That's very tough to do with a multimeter. The digital output line of the RF
receiver module will output constant noise pulses in the absence of a
signal. While it's not from a CM15A, I've published some oscilloscope screen
shots from a similar receiver at http://www.mbx-usa.com/rf-noise.htm. The
bottom, magenta trace resembles the ocilloscope trace you would see from the
CM15A receiver.

Pin 1 of the Cypress controller is the RF data line. It will vary between 0V
& 5V. You can record it using a soundcard line-in input (NOT the mic input)
but you should use a voltage divider like I show at
http://www.mbx-usa.com/learn.htm to reduce the voltage to the 1-2V range
expected at line-in. The frequency is in the audio range (~1kHz). You can
see similar recordings at both of the cited URLs (the green traces on blue
backgrounds). Actually, you can hear a distinct rat-a-tat-tat of a code via
the soundcard so recording may not be needed to tell whether the RF receiver
output is OK. My expectation would be that the RF receiver is OK. 

tony_9221@yahoo.com (Tony_king) wrote:

>Hi Dave,
>My remote is just several inches near the CM15A, so not a distance
>problem. I also double checked the transeiver house codes, all are
>selected. But CM15A still can't react to any RF signals. I wonder if I
>can use the multimeter to check the RF receiver daughter board in the
>CM15A to see if it really receives the signal. Can you give me some
>hints of how to do this?
>
>Thanks!
>
>Tony

I used the multimeter to check the output pin of the RF daughter
board. Before I press the X10 remote button, the pointer of the
multimeter is sweeping at 2.5V as I remember, when I press the button,
the Pointer sweep left to 1V. So I presume the RF receiver is working.

Then that is strange why it didn't process the incoming signal. One
question:does that tranceived house code configuration stored in the
CM15A? I doubt if it is not successfully stored.

The "Transceived House Codes" settings are stored in the interface. Mine
have disappeared 3-4 times now. Since I'm not interested in the X-10
software or firmware, I haven't explored why it gets wiped out.

tony_9221@yahoo.com (Tony_king) wrote:

>I used the multimeter to check the output pin of the RF daughter
>board. Before I press the X10 remote button, the pointer of the
>multimeter is sweeping at 2.5V as I remember, when I press the button,
>the Pointer sweep left to 1V. So I presume the RF receiver is working.
>
>Then that is strange why it didn't process the incoming signal. One
>question:does that tranceived house code configuration stored in the
>CM15A? I doubt if it is not successfully stored.