Type of modulation

[Al542]

I have a scanner that can tune to 310mhz and can be set to any type of modulation. I'm trying to listen in to see what interferes with my alarm once in a while. Does anyone know what mode of modulation that X-10 is using. As in AM, FM, FSK or other.
Thanks
Al

[dhouston]

OOK - On-Off-Keying which is a subset of ASK - Amplitude-Shift-Keying.
There's very few systems using 310MHz so I doubt you are seeing interference from non-X10 sources. A Palmpad lost under couch cushions is a frequent culprit.
There's a brief description here...
https://www.laser.com/dhouston/rf.html