Sorry I am a little tardy getting back to you on this. I was gone much of today, and am doing catch up now. You have raised a number of issues, and I will try to answer them all in this one response.
I have found that in-band noise (reading near 120KHz) can block X10 commands at levels as low as 100mVpp (.10 on the XTBM display). So you have some serious noise to deal with.
The repeater check is performed when the XTBM is first plugged into a receptacle. At that point the AGC is using a default value that works well for most installations. It is possible to miss the repeated command if there is noise or a signal sucker on that circuit. This issue has been reported by several people, and I am not sure how best to deal with it. Many of us hate to wait for anything, so I didn't want to delay the repeater check for several seconds every time the unit is plugged in.
While the XTBM usually does a good job of detecting noise, it can be confused trying to decode noise that looks like a X10 command. I considered displaying the "X10 amplitude" as noise if the X10 command is not properly decoded. The problem is that valid X10 commands that are of marginal amplitude could also be displayed just as noise. That may be just as confusing. I can see people saying: "Why does the XTBM ignore X10 commands from my ___ and display them just as noise?"
I have also seen that HIGH NOISE / NOISE DECREASE when the XTBM is plugged in. It appears to be the plug not making positive contact as it is plugged in. That can generate some noise that takes a few seconds to dissipate. Again, this could be suppressed by delaying the display for a few seconds.
Your question on the XTB-IIR not reliably seeing the Maxi Controller is probably due to your high noise level. The XTB-IIR does incorporate AGC, so it will raise its detection above the background noise level. In fact the default condition raises it one step higher than necessary to further desensitize it to any background noise. There is a mode option to not add that additional step that will give it more sensitivity. But the real issue is to isolate your noisemakers so that the XTB-IIR is not raising the threshold too high. You might also look for potential signal suckers on the Maxi Controller circuit that are attenuating its signal level. The PSC05 does not have AGC, and relies on there being very little noise directly in the X10 passband.
Regarding the Stargate seeing the repeater check, but the XTBM not, something is corrupting that signal enough that the XTBM does not pick it up with the default values seeded into the digital filters when it is first plugged in.
I have no idea why the Stargate saw a P ON / P OFF sequence instead of the P Hail Acknowledge. The XTBM only transmits the Hail Acknowledge. I have seen noise morph one command into another, but I don't see that producing the ON / OFF sequence. My only guess is that there is something else in the installation that generated the ON / OFF sequence.
Those voltage readings indicate both phases are indeed connected. Again, those higher noise numbers must be pursued. Anything above .05 can cause a problem if it is in the X10 passband. Note that some noise may only be indicated as Bad Start Codes (BSCs) because they were trying to be decoded, and not give actual voltage readings.
If you have a XTB-IIR driving your system, and you are only seeing X10 voltage levels of 0.75V or 1.77V, those circuits have some SERIOUS signal suckers. That can explain why the XTBM repeater test isn't working. Many people report the XTB-IIR signal saturates their XTBM readings (over 10V), and even the lowest readings are typically in the 2 to 5V range.
I suggest you use the XTBM as a tool to find those devices that are generating the noise and sucking down the signal levels. Then isolate them with appropriate filters.
Good luck, and I will try to check this thread whenever I log on.
Jeff
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Topic: XTBM: Noise levels, not always seeing repeater, and XTB-IIR not seeing some stuf (Read 14194 times)