On 23/12/2010 16:15, Tim Lamb wrote:
In message , Tim Lamb
writes
In message
,
writes
On Dec 22, 7:37 pm, Tim Lamb wrote:
Somebody has to ask this question:-)

Multi function filament bulb set. Chinese manufacture (in case you
wondered) fuse OK but no lights. Appear to be well made.

Control box is sealed and has a single pushbutton to select the
operation. Is there any point in forcing the box open in the hope of
by-passing the electronics?

regards
--
Tim Lamb

Assuming it's the common type of box I'm thinking of, prise off the
flap at the bottom, which is held at the sides by clips that will
probably break. Open carefully unless you want the fun of working out
which green wire came from where. Beneath the flap you will find the
wires connect via little tubular sockets to a row of pins. The
connections often come loose despite being held by blobs of
silicone.The mechanism that grips the wires also has a tendency to
slice through them. If no lights at all are on, it's probably the
power wires that are at fault, (or the wallwart's duff). With the pins
exposed you can easily check. Beware of shorting pins together as that
can kill the electronics.

Sounds likely. We have two sets with identical symptoms.

The controller is referred as *light chain control box* and presumably
the manufacturer as YIN YU.

OK. Back off.

All connections look sound so it must be the 'lectronics.

180 bulbs at 6V spread across 5 connections. So that's a common and 4
lots of 45?

So which is the common? Ah! I see the requirement and use of the
multimeter:-)

Hmmm.... All 4 circuits are open! I suppose it only takes 4 bulbs to
fail.... I wonder if Wyvale had many returns?

Shame really as the assembly job is very good. The purchasing dept.
spent too little on getting reliable bulbs:-(

regards


HI Tim

I spend a few hours earlier this week trying to sort some similar light
strings. One very useful gizmo that (I think) came with a set of lights
is a holder that takes a couple of AA batteries and has two contact
springs at the top that are the same spacing as the bulbs. (I guess you
could use one of the old-fashioned 'bicycle lamp' batteries with the
springy brass contacts, if they still exist).

Using this thing it's a (relatively) simple task to whip the bulbs out
one by one and check them (even though yours may be under-run at 3v /
4.5v they'll still light) - and then swap bulbs until you end up with as
many working sections as possible. Mine were 24v, with ten in a string.

My bulbs were the sort that fail short-circuit - and a couple of runs of
lights had more than one blown bulb - which suggested that they didn't
like the over-voltage caused when one went short...

Decision time for us @ 12th night - we have probably more than ten sets
of lights - dating back many years (some 50+) - and I'm told we're going
to have to bin some of them.... (rather than put them in the 'it'll come
in handy one day' box!)

Adrian