Elk ESM1...sensitivity?

[Guy Lavoie]

I had one of those "hmmm" moments the other day: I was troubleshooting a weak X10 signal problem around my PC/lab area and at one point I had my ESM1 signal meter plugged in alongside a PSC-05 that wasn't connected to anything. I was sending X10 from another part of the house and couldn't see any indication of a signal on the ESM1...yet the LED on the PSC-05 was blinking twice, indicating that it was receiving a valid X10 signal pair.

I thought that the ESM1's lowest LED bar would indicate a very weak signal that some X10 receivers might miss, but instead it appears that the PSC-05 can reliably receive a signal that is too weak for any indication on the ESM1. Has anyone else ever noticed this? The ESM1 has been very useful and I don't think that its defective or anything, but I am a bit surprised. Or have I discovered a magic PSC-05?

 

[JohnBullard]

Guy,

You must have a magic PSC-05 ! Is this one of the one's you modded?

 

[Guy Lavoie]

Well, the only "mod" I did is the capacitor mod, which concerns signal transmission for the most part. Other then that', its stock. I have several of these, so I should try out a few more...

 

[BraveSirRobbin]

Well, the only "mod" I did is the capacitor mod, which concerns signal transmission for the most part.

Is this mod really worth the effort Guy? Have you noticed an increase in signal strength?

 

[Guy Lavoie]

Yes, definately. This mod came about as a result of not being able to send X10 reliably when I first got my Ocelot. I could see that the Ocelot was retrying the transmission a total of 5 times before giving up. I could also see that the PSC-05's LED would dim slightly when it was transmitting (or trying to). Its after examining the TW-523's schematic and hearing about the previous "solution" of cutting out the LED to save power that I came up with the idea of trying a larger capacitor to replace C12. I found that I could physically fit a 470uF cap in the place of the 100uF that was there. It worked really well after that so I mentioned it on the Futurestandard ADI mailing list and CHA newsgroup, and many other people have since used this mod with good results themselves.

 

[BraveSirRobbin]

Hey, I might try it. I believe I did this on a TW523 and didn't notice much change, but can't really remember the details (man, I'm getting old!).

Thanks again.