Vintage Christmas Tree lights

[pifcolights]

Does anyone remember if the petal and diamond shade lights of the 70's and 80's were made more robustly than the sort of plastic they use today? Sadly i can't get the petal shades for my Premier 'Yuletide Nostagia' anymore as Premier don't stock replacement shades. Looked on Ebay and they are the type that twist on not slide over the lamp holder. I should of bought off Noma as i know for a fact they have a better spares department. Would i be better off buying a set of Vintage Pifco lights with the shades hard wired into the bulb holder? Secondly although the old transparent green cable is redundant and deemed not safe by modern safety regulations how come i see PAT testers passing these sort of lights as safe in charity shops and Ebay? From my memory the single insulated sets were quite tough cabling and not easily punctured.

[broadgage]

The older style single covered wire (often but not always transparent) does not comply with current regulations for mains voltage.
IMHO it is not actually dangerous, but it is less potentially less safe than either double insulated wire, or the use of a much reduced voltage from a suitable transformer.

I see no reason why Christmas lighting sets with single covered wire should not be used by competent persons, but would be very doubtful about selling them as working appliances as distinct from vintage collectables.

I have little faith in PAT test certificates.

[pifcolights]

Thanks for that information Broadgage. In answer to my question about shades, would iI be better getting a set where the shades are not removable i.e. some of the Jewel, mini bells and glitter lites were hard wired into the bulb holder.

[Herald1360]

If the problem is missing "shades" it sounds like another set for spares would be worth finding. Fixed shades couldn't go missing but if they get broken replacement is more of a pain.

Meanwhile why not just use the incomplete set on the tree where you can lose the dodgy lamps in the foliage?

[emeritus]

I am still using a set with the transparent green wire that I bought in the mid-1970's from a market stall in London's Leather Lane street market. The guy had a stall full of them, and they turned out to be re-labelled Woolworths sets with the Woolworths logo obliterated. I think this must have been just before the regulations changed and I assume Woolworths had cleared their stocks of the old soon-to-be non-compliant lamps. It has behaved reliably every year, and is used strung from the picture rail well out of harm's way.

Is there a source of green double insulated single core wire suitable for use with mains christmas tree lights? I couldn't track any down when I needed some a couple of years ago, and used some 500V-rated red wire that I had to hand to convert another set from ring to radial configuration. I presume it counts as double insulated as it has a white core surrounding the wire strands and a red outer layer that seems to be integrally bonded to the white core, which seems to be the way the cables of the latest mains lights I have are constructed.

[paulsherwin]

Poundland sell sets of 20 mains incandescent lights. Presumably the wiring on these is compliant with modern standards. You could just throw the 12V bulbs and holders away.

Actually, these Poundland sets are much better than you might expect for the price, though the cabling is a bit stingy. I have a set which will be on its third Christmas this year, and no bulbs have blown yet.

[richard.cs]

On some of my older sets of lights with hard-to-find lamps I have added a capacitor dropper. This reduces the running current but doesn't really improve inrush, A NTC thermistor would be a nice addition but they run hot and then I'd have to find somewhere to put it.

On mine an X2 capacitor of the right value (I don't remember exactly, maybe 2u2) to drop the chain of lamps to 90% of the nominal voltage is epoxied onto the back of the 13A plug with short flying leads on the inside. It had to go diagonally so that it had reasonable clearance to the inner guts but when finished it looks quite neat (much like those plugs with the extra handle on the back for those with weak grip) and isn't going anywhere. Obviously some sufficiently violent impact could knock it free and perhaps expose a live part but I suspect they're comparable with those needed to shatter the plug anyway. It's certainly not the most dubious piece of wiring in my Christmas light collection.*

What I'll get around to sometime is a proper transformer dropper on an extension lead. I'm imaginging taking a 24V plug-pack transformer, opening it up and wiring the transformer inside in anti-series with the mains to give the voltage drop, then bringing this out to a 6-way extension dedicated to Christmas light use. If there's room for an NTC thermistor or other form of soft start then that'd be great. Obviously it'd need something like a 1A fuse to protect the transformer's secondary in case some daft person plugs a kettle into it.


*I don't recomend anyone doing this but I also have a string of lamps where live and neutral go to two different plugs.

[paulsherwin]

You can add a 1N4007 inside the plug to reduce the power dissipation and extend the bulb life. Some people find the resultant flicker annoying but most can't see it.

[alanworland]

Each year I use a multitude of Christmas lights around the lounge which years ago I developed a 'wiring loom' around the walls using BICC BURNDY plugs and sockets - I just plug in what is required.
These are all fed from a triac controller which is wound up from zero to an under run condition, seems to work well enough, the bulbs date back to the fifties.

Alan

[Brigham]

A dedicated circuit for Christmas lights? Now that is Class.

[Station X]

Four posts moved to a new thread here:-

https://www.vintage-radio.net/forum/...d.php?t=111424

[jjwayle]

Excuse my ignorance but how does the addition of a IN4007 help extend the life of old Christmas light sets? Is it because of the extra 0.7v drop from the diode or to do with half wave rectification or a combo of both?

[paulsherwin]

It chops the AC waveform in half. This doesn't mean the lights run at half power (the calculations are more complex than that) but in practice they will run at about 2/3 power. They still look reasonably bright but run a lot cooler so last a lot longer.

It's easy enough to experiment if anyone's interested.

This technique is obviously only suitable for traditional series string lights connected across the mains. It can't be used for incandescent bulbs used in parallel from a transformer, or any form of LED lighting.

[Tazman1966]

There is a very slight 50Hz flicker noticable I've found...

[paulsherwin]

Sensitivity to flicker varies hugely from one person to the next. Some people will think it looks awful, and others won't be able to see it at all.

[alanworland]

Oh dear! After 50+ years of Christmas service my favourite bulb has given up the ghost!


Lit from below by torch for the photo.

These are still going!


Alan

[DangerMan]

Adding a 1N4007 causes the power in the lamps to be reduced by half, it's the RMS voltage that isn't halved but reduced to 240/sqrt2... so roughly 170V RMS for a 240V mains supply fed via a diode.

[paulsherwin]

Yes, you're quite right. I was in 'lazy summarising mode' when I made post 297.

[Nickthedentist]

Originally Posted by alanworland

Oh dear! After 50+ years of Christmas service my favourite bulb has given up the ghost!

Is there no way you could cut open the glass envelope and fit a modern lamp inside?

[paulsherwin]

You might Nick, with all your fancy dental cutting gear, but that glass will be very thin. Definitely a specialist job, though these things are becoming so rare and desirable now that it may be worth paying a jeweller or glassworker to do it.