Christmas Lights Problem

Naaah! My highest electric bill was $660.29 for the month of July.

Our "new" house (now here 12.5 years :-) is much better insulated than the old one, with smaller floor space but flat-roofed ranch style architecture would often run over $1200/month :-(

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

snip I would put a wire into the input of an audio amplifier. When that wire comes close to a voltage carrying wire you can hear it. All unbroken lights will have the same sound on both sides, the one with a broken light will have mains on one side, and zero on the other side. Happy hunting.

Gross! Yesterday we had our family tradition: drive to Half Moon Bay, go to the 4C's tree farm, and let The Brat lie in the mud and saw down a tree. Then lunch at the Moss Beach Distillery, on a bluff overlooking the coast.

Our PG&E bill peaks at about $150, just about half gas and half electricity. The electricity is about 20 cents per KWH! We don't have air conditioning.

Speaking of global warming, yesterday morning all the houses below us on the hill had beautiful white frosted roofs. I've never seen that before.

And I *just found* the major cause of the jitter in my delay generator digital PLL thing. What looked like random jitter (80 ps RMS!) actually had structure that depended on trigger rate. I isolated a number of squirmy trigger rates, but they weren't divisors of anything on the board, so that let the uP and the switching regulators off the hook. After some poking around with spectrum analyzers and such, the only numbers that fit were local FM radio frequencies! Sure enough, that's what was happening... the jitter would show coherent wiggles at trigger rates that were sub-multiples (like 237:1) of the major FM station frequencies. So I disconnected the background debug pod, blew the firmware into flash memory, and scrinched the board into its extruded enclosure and tightened all the screws: jitter dropped in half! Who woulda thunk it? Now I can goof off until some time in January.

John

Some of these strings have three wires twisted together so you can plug another string into the far end and not need so many extension cords. I just take a matching socket off a similar string and use it to test the bulbs from a battery or AC adapter.

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

At least it was only one station (hope they had some good music on). I have a case in Europe right now where it's at least one police pager plus a few FM stations intermodding into a unit. And none of the EMI companies I contacted over there wants to come out to take a few plots. Drat.

--
Regards, Joerg

http://www.analogconsultants.com

I like Fred's and John's suggestion. TDR would be the nerdy way of doing it, very cool. A bit less nerdy and so far I have only used it for long stretched-out lines like LAN cables: Take a saw-tooth generator, the clip to ground and the tip to one prong of the suspect light chain. Then move an AM radio along the chain until the buzz drops. That's where it's cut off, usually. The generator I use is decidedly low tech but has helped me diagnose more than any of the fancy tools in the lab. It's a pencil-shape $5-edition of a signal injector from some European Radio-Shack type vendor.

--
Regards, Joerg

http://www.analogconsultants.com

--
If it\'s just a series string and you\'ve got a blown lamp, I\'d
generate some high-voltage pulses using a battery on the secondary
of an output transformer with the primary hooked across the string\'s
plug, and then go looking for the arc.

John Fields a écrit :

A Tesla tree?

--
Thanks,
Fred.

Good idea!

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

I once was testing a circuit in a client's building that had steel studs in the walls that resonated exactly to an FM station... produced some really weird results ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

Hey! I have plenty of good ideas, if you will just take the time to read between the bad jokes! ;-)

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Thanks! Ordered. Should be here in time for the tear-down. With a few thousand lights they're hardly noticeable unless you get up close and personal... and it's on the side where no one is likely to stand.

I did have to have an electrician come and pull me a dedicated circuit for my fish tank... chiller plus Christmas tree was just too much load ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

Holy crap, why not just buy a replacement bulb and start on one end and replace each one until all the lights work again?

Actually, the math corresponds to effects from at least 3 stations,

88.5 FM (KQED, the Public Propaganda System), 96.5 (KOIT, geezer music) and something big at 140 MHz, probably a TV station. Dangling a lead out a spectrum analyzer, this place is a horror... there's a big line every 200 KHz clean across the FM band. Heck, we can see the same thing on a scope FFT. We look up at Sutro Tower out our back window, maybe the world's biggest free EMI test facility.

John

What if there are TWO bad bulbs in the series string? You could be at it till you die, and not find the bad bulb with your method.

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

140MHz won't be TV, should be something else. The worst I have ever seen is this site in Rotterdam, Netherlands. Towers all around, ERP levels well north of 10kW and a emergency services paging station on the roof. Oh man. And that is a hospital.

--
Regards, Joerg

http://www.analogconsultants.com

I know Michael. And the jokes are not ALL bad ;-)

Merry Christmas to you and yours!

And to all those politically correct weenies who object to me saying "Merry Christmas", your holiday greeting is, "May You Rot in Hell" ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

Wow, more than 15A or 20A? Is that a Griswold Christmas tree? Anyhow, I'd probably have done it the redneck way, get a bright red extension cord at Ace Hardware and run that along the hallway.

--
Regards, Joerg

http://www.analogconsultants.com

If there is enough rf floating about the dead bulbs are the ones that are not glowing.