Please login or register.

Login with username, password and session length
Advanced search  

News:

The X10Hub (PiX10Hub) is here! Created by the Community, for the Community.:)% #:)

Pages: 1 2 [3] 4 5

Author Topic: X10 Signal Meter  (Read 101673 times)

dave w

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 137
  • Posts: 5995
« Last Edit: July 25, 2009, 01:03:32 PM by dave w »
Logged
"This aftershave makes me look fat"

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #31 on: July 25, 2009, 01:01:02 PM »

Oh, I vote for black because it matches better with my OptiVisor. 

Black cases have been ordered...

Jeff
Logged
X-10 automation since the BSR days

GregH

  • Full Member
  • ***
  • Helpful Post Rating: 0
  • Posts: 63
Re: X10 Signal Meter
« Reply #32 on: July 27, 2009, 09:56:41 PM »

How does less than 4 bucks sound?   :D

That would send my wife over the edge!  rofl
Logged

dave w

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 137
  • Posts: 5995
Re: X10 Signal Meter
« Reply #33 on: July 28, 2009, 12:22:36 PM »

Black cases have been ordered...
Jeff
s-s-s-s-s-s-snuff!

...silence...



(and that friends, is the sound of "bated breath")
« Last Edit: July 28, 2009, 12:26:46 PM by dave w »
Logged
"This aftershave makes me look fat"

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #34 on: August 03, 2009, 05:27:20 PM »

I would like some feedback here.

I added the code that transmits a P1 ON in response to a significant increase in noise, and confirmed that was working by injecting a variable noise level from my Wavetek.

Then I plugged in that infamous Cellet cellphone charger.  The meter immediately started logging bad start codes, but there was virtually no increase in indicated noise level, and the noise increase detector was not triggered.

The meter samples the powerline in three windows:  just before, during, and just after the X10 transmission window.  It normally displays the signal or noise level during the X10 window.  Using a storage scope to capture noise from the Cellet charger, its switching regulator only pulses on in the X10 reception window a few times a second.  While that is certainly enough to corrupt X10 transmissions, it is not enough to raise the average noise level significantly.  Looking just during X10 reception windows, the average noise remains below 25mV.  However, looking over the whole cycle, the noise gets up to almost a volt when there is a load on the charger.  Yes, that is one nasty device.

To be useful, I think the meter should identify even very intermittent noise capable of causing X10 communications problems.  I modified the A/D sampling routines to not only capture peak noise over an entire  X10 transmission, but also peak noise during each individual X10 sample window.  That does show an increase when the charger is plugged in, but still less than 100mV.  However, that is certainly capable of causing bad start codes, and a serious X10 reliability problem.  Maybe the best indicator is the fact that the meter is displaying a continuous stream of bad start codes whenever the charger is plugged in.

Displaying peak noise clearly works better for a device such as the Cellet charger.  It will also give a good reading for constant noise, such as that produced by a wireless intercom.  Noise injected from my Wavetek reads virtually the same with either an average or a peak detector.  The peak detector does have a problem with very short high-energy pulses, which indicate an elevated noise level, but may not be long enough to corrupt X10 communications.  My next step is to gate the max amplitude detector with pulse count, and ignore any high amplitude pulse that does not last long enough to be detected as a X10 logic "1".

One other option is to examine noise over other regions of the waveform.  The Cellet charger is much more active during the mid portion of the sinewave, which is where it generates most of its noise.  However, that noise has no impact at all on X10 communication.  Sampling over more of the waveform could "red-flag" devices as filter candidates even though adding the filter does nothing to improve X10 system reliability.  Because of this, I thought it best to focus just on the X10 reception window.  The other windows are used to help isolate X10 traffic from the background noise level on either side of the X10 sample window.

Any suggestions as I continue to work this issue are welcome.

Jeff
Logged
X-10 automation since the BSR days

steven r

  • Advanced Member
  • Hero Member
  • ******
  • Helpful Post Rating: 74
  • Posts: 2189
  • Halloween with X10
Re: X10 Signal Meter
« Reply #35 on: August 03, 2009, 06:06:07 PM »

...Any suggestions as I continue to work this issue are welcome...
You're so far ahead of most of us on the whole issue of noise and X10 that I humble in you presence.
I'll certainly let you know should I think of something, however.  ;D
Logged
BVC let's me tell my camera where to go!
:) Murphy is my beta testing pal. He helps me find problems whether I like it or not. :)

Brian H

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 289
  • Posts: 12714
Re: X10 Signal Meter
« Reply #36 on: August 04, 2009, 06:53:36 AM »

Though my test equipment is not close to what you have Jeff. I have seen devices give me a bar or two on my ESM1. While my scope shows the noise on the peak of the waveform. So maybe looking around the X10 signal area maybe be better.
Logged

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #37 on: August 04, 2009, 09:44:56 AM »

I have seen devices give me a bar or two on my ESM1. While my scope shows the noise on the peak of the waveform. So maybe looking around the X10 signal area maybe be better.

The Cellet charger gives one flickering bar on the ESM1, whether it is loaded or not.  Because the Cellet noise reaches almost a volt during the peak of the waveform when loaded, the ESM1 must be sampling only during the X10 reception window too.

The noise detector will display peak amplitude of noise bursts in the X10 reception window that are long enough to trigger false "1" bits.

Followup:  That method is working well.  It ignores the big fat transient we have right in the middle of the X10 sample window, but easily recognizes the noise produced by the Cellet charger.

Jeff
« Last Edit: August 04, 2009, 02:33:02 PM by JeffVolp »
Logged
X-10 automation since the BSR days

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #38 on: August 20, 2009, 06:54:30 PM »

The XTBM signal meter is almost here.  I ordered the remaining components today, and will assemble the first "production" unit next week.

While I have been thoroughly testing the various modes, I would like some feedback to see if there are any usability issues I haven't thought of.  Please contact me directly if you would like to receive one of the first few kits at a special introductory price.

Jeff
Logged
X-10 automation since the BSR days

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #39 on: August 28, 2009, 01:25:09 PM »

Here is a photo of the XTBM "production prototype" PCB:

http://jvde.us/xtb/XTBM_v10_pcb.jpg

Here is a draft of the description:

http://jvde.us/xtb/XTBM_X10_signal_meter.doc

For those who have already ordered kits, I am sorting and packaging components now, and your kits will be on the way tomorrow or Monday.

Thanks,

Jeff
Logged
X-10 automation since the BSR days

Brian H

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 289
  • Posts: 12714
Re: X10 Signal Meter
« Reply #40 on: August 28, 2009, 04:01:31 PM »

Looks like it will be a welcomed addition to many X10 installations.
Logged

dave w

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 137
  • Posts: 5995
Re: X10 Signal Meter
« Reply #41 on: August 28, 2009, 06:08:44 PM »

Weller temp controlled iron and 63/37 solder excitedly waiting for USPS delivery. (I'm vibrating...which may make soldering difficult).  :)%
Logged
"This aftershave makes me look fat"

GregH

  • Full Member
  • ***
  • Helpful Post Rating: 0
  • Posts: 63
Re: X10 Signal Meter
« Reply #42 on: August 29, 2009, 10:11:24 AM »

Yeah, I'm looking forward to building, and playing, with the XTMB!
Logged

dave w

  • Community Organizer
  • Hero Member
  • ***
  • Helpful Post Rating: 137
  • Posts: 5995
Re: X10 Signal Meter
« Reply #43 on: September 03, 2009, 12:19:15 PM »

FYI to kit buyers.

The kit is an easy build. Very high quality PC board, and well laid out. I'm not finished building yet, but am impressed with the quality so far.
One tip would be to print the jpg color pix of the assembled PC board to a good color printer for parts placement reference during build.

Especially important if you do not know resistor color code. Let's see, how does that go again; "Bad Boys ......"  ;D
Logged
"This aftershave makes me look fat"

JeffVolp

  • Moderator
  • Hero Member
  • *
  • Helpful Post Rating: 107
  • Posts: 2064
    • XTB Home Page
Re: X10 Signal Meter
« Reply #44 on: September 03, 2009, 12:52:07 PM »

As an example of how to use the XTBM, I have the prototype plugged into our "problem" X10 circuit.  That circuit feeds seven X10 devices, including three transmitters.  With no booster in the system, the XTBM was reporting the .13V signal received from the Ocelot's TW523.  Plugging the prototype XTB-R into a standard AC receptacle near the distribution panel boosted that reading to 2.27V.  Peak background noise is .05V.

The meter is displaying the G16 ON/OFF toggle that runs our hot water recirculation pump several times an hour.

Jeff
Logged
X-10 automation since the BSR days
Pages: 1 2 [3] 4 5
 

X10.com | About X10 | X10 Security Systems | Cameras| Package Deals
© Copyright 2014-2016 X10.com All rights reserved.