Christmas Lights Problem

Depending on how the strings are wired, on of those "no touch" electrical testers will do it, I am referring to the ones that detect electric fields. Usually about $15 at Home Depot.

love to cook with wine. Sometimes I even put it in the food.

there was a widget published in electronic design's circuit page a few years ago, simple, uses capacitive coupling. There is also the "short the plug prongs and ohm meter technique" watch out for the high ohms "fuse" in the base of the bulb thats designed to keep a string going.

see following link, ideas for design # 6351

circuit diagram:

hope this helps

Steve Roberts

I've used an ohm meter and a large, sharp needle. Clip meter lead to plug, then do 'half split' with the needle poking into the wire.

Luhan "Lets put the 'X' back in Xmas"

RatShack has a little amplified speaker, looks like a transistor radio. If you stick a little wire "antenna" on its input, it becomes an e-field sniffer.

John

Presuming you mean series chain lights:

In my first year electronics course I was taught the "half-split" method of fault finding, find the bulb nearest to half way and check which path to the plug is open, then divide that half in half again and check which quater is open - and so on..........

...Jim Thompson

that 21$ amp is worth it just as a bench tool. If they havent cheapened it, it has a really sensitive fet preamp and a agc.

Steve Roberts

Jim Thompson a écrit :

TDR. Given a 66% speed of light and a 50m max light string length (you always have to have the biggest) you should find it in about:

I guess you won't find any faster way :-)

If you don't have a TDR you can use a VNA and then apply an FFT.

That's the pb I'm working on ATM, so I'm self-proclaiming the expert and I can offer you consultancy. In case you feel more inclination to get a longer light string, I can go up to 10km.

Its a pre wired tree. You can't tell what lamp is where on the string on a lot of those because the wires are hidden.

Seems the manufacturers will do just about anything to make their products unrepairable!

On a sunny day (Thu, 21 Dec 2006 08:59:48 -0700) it happened Jim Thompson wrote in :

Sure, apply 1kV via a high resistor, where it arcs the bulb is defective.

You should stick to something you can handle, like candles on a cactus.

Jim Thompson wrote in news: snipped-for-privacy@4ax.com:

you could try this;

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With retail names like "Martha Stewart" what do you expect? I haven't bothered with a tree since I bought my first house. The total extent of decorations this year was a pair of green light bulbs in fixtures on the gateposts at the end of my driveway.

The way I do it is to use a Ohm Meter or continuity tester between the plug and the lamp sockets. I tried to use one of the E-Field line testers and it was usually ambiguous due to the proximity of both wires. It's more labor intensive to pull out the lamps and probe the socket but it does work.

Our cocker spaniel puppy has been chewing the heck out of the tree and light strings. We un-plug them when not in use but it keeps me busy continually doing safety inspections .

There was something written a while back, "You're and Electrical Engineer if..." One was "You're and Electrical Engineer if your family relies on you to fix the Christmas lights, and you have a good time at it."

Pax, Bob Oppenheimer

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Buy another tree?

Just a festive picture here..........

TDR? :)

...Jim Thompson