Re: Need some antenna advice (for my CM15A, of course)

BPL does the same thing as DSL, modulating several different frequencies so that, in effect, they have several parallel channels with each carrying a portion of the message. That gives them the speed (soon to be much, much faster). While I think they can turn individual frequencies on/off to avoid any excessive noise at that frequency, the robustness is mostly because they are using the same methods as Ethernet with the receiver asking for repeats when there are errors.

Can you post the actual powerline bitstream?

You're reading more into 'calibrate' than it really means. In this case, they merely adjust the ESM1 so that it's fullscale reading is the same as the Monterey fullscale reading. Now both are in error by more than 50% whereas the initial ESM1 shows the true peak-to-peak level.

There is one benefit in that it may let you see weaker signals than before.

It should merely be called 1110. Some are intended to be startcodes by the transmitter, some become startcodes because they are created by collisions that also create a valid sequence following them, some are merely collision debris as there is no valid code that follows.

In a split-phase residence, all zero crossings coincide. Half are going positive while the other half are going negative. The only time the phase matters is when a transmitter waits for a positive going zero crossing (needed to trigger the relay on a transceiver).

You're Dave and the required adapter is labeled "PowerLinc II Model 1132B computer interface" which is listed here:

where they also remind the buyer, in big red letters: "Due to the nature of this product, Smarthome cannot offer programming support. We cannot assist in the troubleshooting or development of applications and/or code for this product."

I assume that's because unlike the CM11A, the TW523 and its clones speak a very low level form of X-10.

I became curious about what else was needed because the Smarthome picture shows the TesterLinc curiously devoid of any wires - I wanted to know if it had a wall wart or just a line cord, like the Monterey has. I'm not as hot for the TesterLinc now that I know it's got to be used in tandem with the

1132B. I found it amusing that they hype this one the same way MicroSoft hawks Windows upgrades: "This one really works, honest!" Here's the comment from the site:

"much better value than the previous powerlinc package" - MARK -- SUNRISE, FL

-- Bobby G.

I'm going to try to do that when I reload the software onto a different machine. So far, all I've been able to do is take limited screen shots that only show half of the screen (small monitor set to 640 by 480 - should improve when I change to 1024 by 768).

Since it's a JPG file, it wouldn't be kosher to post them to the newsgroup. The Lynx SW depends heavily on color and graphics to display the bitstream, using different forms of shading and different colors to represent various items. If I can't figure out how to post them to my Yahoo site so that others can see them, I'm open to suggestions as to where to post them.

I'm a little confused (well maybe more than a little). Do both meters now NOT read peak-to-peak and only peak to baseline?

I'm assuming that's merely the side effect of expanding the scale.

-- Bobby G.

It's not exactly straightforward since both (I assume) rectify the signal and only measure the positive half.

My pre-ELK ESM1 reads full scale when plugged into the same powerstrip as a TW523 or any other pre-CM11A X-10 PLC transmitter. All of these output about

10Vpp. The bargraph really represents 0.2Vpp to 10Vpp.

The ELK ESM1 reads fullscale when plugged into the same powerstrip as a CM11A which outputs about 5Vpp (actually, a bit less). IIRC, the Monterey is fullscale @ 4.096Vpp.

There's a potentiometer inside the ESM1 that is used to set fullscale.

Yes, the effect is to make the first bar twice as sensitive as the original design. It also doubles the noise sensitivity.

Since it is more likely that you'll want to compare weak signals than 10Vpp signals I can't argue with their decision. But, none of the testers give a complete picture.

The original PowerLinc did not output all of the bits but only those that represented a valid signal. That's less than ideal for troubleshooting. It also had some 'hearing' problems, frequently going deaf to the powerline.

I think the programming disclaimer is probably because they were overwhelmed with questions from amateur programmers. It may also be because there's a USB version and low level USB programming is not simple. They published the serial protocol for the first PowerLinc but it was TTL/RS232 only; there was no USB version.

On the deafness problem, I saw the same problem with the LampLinc 2000STW. All three that I have would stop responding and the LED would blink at random. LM14As worked fine in the same circuits and I could see nothing amiss with my scope/Scope-Test2. If it was noise, it was out of the frequency band of the Scope-Test2. The LampLinc was OK if used on the building.

The recent thread about phantom signals when a paper shredder ran caused me to test the LampLincs again. For the past couple of weeks they've been OK in the same circuits which gave them trouble before. The only change I'm aware of is that I gave an older desktop machine to a niece. There have also been

2-3 changes >> but it's pre-coffee in the morning so I can't recall its name (nor mine). >

Actaully, it's an HID-USB device, which is pretty simple. It's file I/O with

9 byte packets (in the case of this particular device.) Other than some not so well documented Windows stuff required to actually find the device path so that you can open the pseudo file, it's simpler than serial programming.

------------------------------------- Dean Roddey Chairman/CTO, Charmed Quark Systems

Mark my words. You will end up buying the ACT 004. You seem serious about having the ability to really see what's going on with your installation and you want to be able to do so from anywhere in the house. IOW, you're like me (at least in that regard). The TesterLinc is tempting but I don't think it's going to be "satisfying" in telling you what you want to know. Consider biting the bullet... most places will give you a 30 day return privilege (some exclude test equipment for obvious reasons).

From:Robert Green ROBERT snipped-for-privacy@YAH00.COM

We're beginning to own a lot of the same test equipment, that's for sure! :-) I've even thought that the ESM1's are cheap enough to use as sensors at the breaker panel and the far ends of the longest branches. If any one of three starting showing signal loss, I'd not only know about it, I could vector in on it. As much as I can, I try to keep tracking of what gets plugged into the AC outlets, but it's not always possible with other technologically-inclined family members around. It seems to me that someone's got a mod to turn old appliance modules with bad cams into remote signal strength sensors. To me that status of the powerline is almost like the house's pulse.

Dave, if you're reading this, do you know how much distance there can be between the ESM1 wall wart and the meter assembly? Would it be possible to mount the wall wart at the breaker panel and cut the wires from the meter head to the PS and splice a very long cable in between so that the wallwart sits in the basement and the LED display is mounted so I can see it from my desk? Somewhere I read that the distance might be critical, but I can't seem to find that message again in Google.

The TesterLinc lost its luster when Dave pointed out it came with a rather large tail. I don't like the "units" approach to signal measurement when there's already a pretty good standard to use: volts. I suppose I could mount the interface and an extension cord along with the TesterLinc in a larger box, but that's pretty kludgy.

The ACT unit's ability to read 220V could be a big plus in my next house. Even the Monterey can't do that. I wish either the ACT or the Monterey had a USB links. Then my choice would be simple! Sometimes you can learn an awful lot from stored logs. Taking and saving a snapshot each quarter would reveal an overall system degradation you might never notice otherwise.

I should be cleaning out the grill for the holiday but here I am fiddling with Lynx and the newly arrived OmniLT. This stuff is just too much fun. The puzzle for today is how to switch over from a leased ADT unit to the OmniLT with the least amount of disruption. I was thinking of reusing ADT's old door switches and sensors, but the only way to really stay protected

24x7 is by getting the LT operational on all its own sensors. Then I can use the ADT stuff as backup or HA sensors once I'm sure the LT has worked out.

-- Bobby G.

I was afraid that might be the case. A more primitive way to get "signal health" feedback might be to design a "sensor" using a combination of one of the filter designs floating around the net and an appliance module. If I can find a filter design that offers variable attenuation, then I can balance the signal to an appliance module (for convenience, I'll call it an ASTM for Attentuated Signal Test Module) so that it just managed to fire. These modules could serve as Go/No Go signal indicators.

Any disturbance to the powerline from a new noisy appliance or a signal sucker would likely make at least one of the ASTMs deaf. All I need to do is run a signal wire back from the ASTM to a central panel. If the house wiring's OK, all ASTM's will respond to their appropriate signals. If there's something amiss, one of the modules will fail to operate, no closure will occur and I can be alerted. HomeSeer could run the diagnostic a few times a day.

I'd like to implement something like this because on occasion something will get plugged in that will have only marginal effect on the main house wiring. It's the second signal sucker that causes real trouble and makes it hard to trace the problem. I've had a number of "sucker hunts" and they are miserable, time-wasting processes. I'm willing to spend some money to lock them down early.

Truth be told, I'd rather have modified ESM1 sensors, though, because I'd get actually voltage levels and not just a "set point" gauge. It may turn out that the ASTMs would be a better, more automatic way of checking signal health on a daily basis.

Agreed, but it's a lot easier and cheaper (for me, at least) to run 12V than

110VAC. I guess I could just pull out the wire cutters and see what affect various lengths of wire have on the ESM1.

I'm a little confused. Are they saying that not only the peak voltage is important, but the length of time the signal is at or near that peak?

For instance, when looking at:

and the image dated 8/20/01 2:37PM would it be reasonable to say that each of the separate vertical magenta trace lines represents a "count?"

I can imagine a need for a 220V capable analyzer in dealing with phase problems in a house with a number of 220V appliances. Not a big need, but it could be useful. It's nice to know I could eaily modify the ESM1 to read signal strength on a 220V line

-- Bobby G.

I don't think there is any simple way to use an appliance module as a signal strength indicator. The PLC_IN level is diode limited (i.e. it will never be greater than about ±0.7V).

The ESM1 transformer output is 12V AC. You should be able to lengthen it, within reason, without serious degradation but it would be better to just plug it into a 120V extension cord. In general, the higher the voltage the longer runs can be without losses.

Actually, both signal strength and number of cycles are important. The X-10 PLC protocol (both standard and extended commands) is explained in detail in XTC798.DOC available on the X-10 web site. I've reformatted it as a text file (the original is nearly impossible to read) and made it available on my web page.

The first paragraph explains why the cycle count is important.

It's a simple matter to c>> about having the ability to really see what's going on with your

There would be no need for a filter. The PLC_IN circuitry in the appliance module already has a tuned filter. It has the advantage of being X-10's own design so it should pass the range of frequencies that all X-10 made devices are affected by.

The disadvantage is that it is not isolated from the mains.

Why not just put a module that will respond to STATUS REQUEST on each circuit and poll them periodically? That requires a signal to traverse the route in both directions.

If I ever finish some other projects, I've thought about creating some modules that would report temperature and ambient light levels using extended codes that could be triggered by a STATUS REQUEST.

The best thing to do would be to replace the PIC16C711 in the ESM1 with a newer pin-compatible PIC (e.g. PIC16F88) and adding a serial output on one of the unused pins. The code would be fairly simple. But, if all ESM1s are like mine, desoldering the PIC is very difficult. I gave up after struggling with it for about an hour without freeing a single pin. I think it requires more sophisticated (and more costly) tools than are in my kit. I've never had to give up on one before this.

No. They're saying what that paragraph says. If the signal is weak, you may miss some 120kHz cycles.

No. Each of the magenta bursts represents ~120 cycles or counts. The horizontal resolution in that picture cannot show the detail. I have other screenshots that show ~1ms but I'd have to hunt them down.

X-10 says transmitters should send continuous cycles of 120kHz for 1ms, starting as soon as possible after ZC. 1ms of 120kHz gives 120 cycles (or counts). The receiver window is 650µs wide starting 250µs after ZC. Only 78 cycles can fit in the 650µs window. 48 cycles represents 61.5% of the expected 78. If the amplitude is marginal, some cycles will be missed but the accuracy will improve as the signal strength increases.

The TW523 does it differently, presenting a demodulated data envelope. Most applications that interface with it check for the presence/absence of the data envelope mid-way through the acceptance window.

Maybe there's something that I don't understand but I don't see how that tells you anything of value.