1) inspect the string for broken or cracked bulbs. Usually caused by
careless handling when putting them away. Replace as needed
2) check the fuses (located in the plug end) with a multi meter. Replace as
needed.
3) Locate the first unlit bulb in the bad section and replace it with a
known good bulb
4) if still unlit. take the bulb you just pulled out (bulb1) and put it in
the second unlit bulb slot.
5) if still unlit, take the bulb you just pulled out (bulb2) and put it in
the third unlit bulb slot.
6) repeat. working your way down the line. When the string lights, throw the
bulb in your hand away.

This will only work if there is only one failed bulb. All bets are off if
there are two or more failures
My experience is that most bad lights are caused from rough handling
(dropping on to the floor) and are usually restricted to broken bulbs. A
truely bad bulb will usually be restricted to one per chain. THere are
actually two filaments in each bulb. The light producing filament and a
shunt filament. If the light producing filament burns out, the shunt
filament will allow enough current to flow to light the other lights to
light but at reduced voltage. it is only when both filaments burnout that
the string dies.

IF still a no go, go to local home center and buy a bad bulb detector for
$3. get the type where you insert the bulb into a hole. It seems to work
better than the type where you just touch the bulb. I suggest this as a last
resort because they don't work too well but they have their place.
http://www.howstuffworks.com/question270.htm

Just remember, the lights were working when you took them down (in April?).
THey don't go bad sitting in storage. THey failed because of rough handling
in the taking down phase. Treat them gently and you will have fewer problems
next Christmas.

"Hybyd2" wrote in message
ink.net...
For one who has the time but is low on funds ... how does one fix those
strings of Christmas tree / colored lights that have the bulbs in series -
presumably, if one bulb blows they all get knocked out? I have a
multimeter and several non-working strings (so hopefully there are plenty
of spare light bulbs).

Suggestions?

Thanks,

Henry