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Help with a very old electrical issue

jebnight

New Member
Hello!

First, thanks for bearing with this post. I'm not an electrician at all.

Second, I have something I'd like to fix. It was a simple light fixture that used edison bulbs inside an R2-D2 ceramic model. This was made in 1978. The fixture worked until a week ago. For years, I realized even without electrical expertise, that a cord like this with this set up would not likely work for 40 years, but it did. The fixture simply stopped working when plugged in. There are small burns at the cord ties.

I have three pictures here to show. My main question is whether the fixture is jury rigged or is it an assembly that can be purchased? Either way, I was hoping to get opinions on a modern alternative. I would like to note that these edison bulb fixtures allowed for the lights to turn on and off. It would take maybe 2-3 minutes to warm up and then the sequence would start. I want to say two lights would activate for about a minute or two then turn off and two others would then turn on, etc.

Third, yes this is silly, impractical, and nostalgic. I realize that but I still would like to find a solution to this purely for the sake of solving a problem.

Thank you for your time and expertise. I hope there are some folks here that can easily offer a modern alternative to this device.

lights1.jpglights2.jpglights3.jpg
 

audioguru

Well-Known Member
Most Helpful Member
The old cord is a fire and shock hazard and should be replaced. An electrician could quickly and safely replace it.
 

MaxHeadRoom78

Well-Known Member
The lamps all appear in parallel, so I don't see how you would get an alternating sequence?
If there is some kind of lamp dimming feature, then there is something in the unit responsible for this.
I am guessing it was a custom made item and nothing off the shelf.
You would need to do some reverse-engineering to find out the exact nature of control.
Max.
 

rjenkinsgb

Well-Known Member
Possibly two or three chains with a thermal flasher bulb in each?
I've not seen those for many years, a filament lamp with an integral bimetal switch and contact so it switches itself on and off, once it fully warms up.

That would fit with the start-up delay.

Edit - found a small version..

I wonder - did that gadget originally have a transformer to run low voltage lamps, where the wire is cut and wire nuts now used?
It could have used a 6V transformer and half a dozen flashing filament lamps all in parallel.
 

jebnight

New Member
Thanks very much everyone for the replies and thoughts.

I wonder - did that gadget originally have a transformer to run low voltage lamps, where the wire is cut and wire nuts now used?
It could have used a 6V transformer and half a dozen flashing filament lamps all in parallel.
rjenkinsgb Actually what you see there in the pictures is all there is. The cord ends tied into the fixture unit with those wire nuts. The fixture is then screwed into the back of the model and sat vertically on the inside. The screw allowed it to hang there. The model has glass elements and holes that allows the light to shine through. The cord on the fixture unit does seem to match the cord with the outlet plug. The fixtures are part of the cord and do have two capped terminal ends.
 

Ylli

Active Member
Can you post a couple pictures of the bulbs? In particular, if you can get a good shot of the filament and filament support structure of the bulb.
 

rjenkinsgb

Well-Known Member
Can you post a couple pictures of the bulbs? In particular, if you can get a good shot of the filament and filament support structure of the bulb.
Agreed; I've never seen them, but there is no reason thermal flasher lamps may not have been manufactured for 110/120V operation in the past.

Looking on ebay etc., that model appears to have possibly been from a kit that was sold at one time, apparently an unpainted body and the electrical setup, for people to finish in their own colours.
There are quite a few about with the same body & cable, but different paintwork; some say they were painted by the original buyers.
 

dr pepper

Well-Known Member
Most Helpful Member
A long time back here in the Uk you could get an inline doofer, you plugged it into the lamp socket, and plugged a lamp into it, and there was a bimetallic switch in it that flashed the lamp, after a warm up.
I've never tried it but I believe neons can be made to sequence I think with just resistors.
 

jebnight

New Member
Agreed; I've never seen them, but there is no reason thermal flasher lamps may not have been manufactured for 110/120V operation in the past.

Looking on ebay etc., that model appears to have possibly been from a kit that was sold at one time, apparently an unpainted body and the electrical setup, for people to finish in their own colours.
There are quite a few about with the same body & cable, but different paintwork; some say they were painted by the original buyers.
This is such a simple solution. For years I thought this was a custom thing not realizing it might have been a kit. I've contacted the ebay sellers I could find. I'll transplant the electrical components if I can actually find a kit that works.

If not, i'll come back and try something like dr pepper and yourself are hinting at. The challenge of figuring that out would be more rewarding but maybe not as practical.

Cheers, folks!
 

Pommie

Well-Known Member
Most Helpful Member
I've never tried it but I believe neons can be made to sequence I think with just resistors.
I believe the flashing neons used a resistor and capacitor in series with the neon across the capacitor. When the capacitor reached the strike voltage of the neon then the neon would light, discharge the capacitor and the whole sequence would repeat.

Mike.
 

gophert

Well-Known Member
Most Helpful Member
I believe the flashing neons used a resistor and capacitor in series with the neon across the capacitor. When the capacitor reached the strike voltage of the neon then the neon would light, discharge the capacitor and the whole sequence would repeat.

Mike.
Neons are bi-directional on AC, did the old neons have a diode to prevent the resistor from discharging the cap?
 

dr pepper

Well-Known Member
Most Helpful Member
I think the neon flash was even simpler, maybe just a resistor & neons, one neon tends to strike first, then warms up increasing its maintain voltage causing another neon to strike, then the whole thing repeats.
Something like that I think.
What you described pomms is how my old timer capacitor leakage tester works.
 

AnalogKid

Well-Known Member
Most Helpful Member
A line-powered neon sequencer requires at least a half-wave rectifier in series with the cirucit. The caps then can be electrolytic if needed for long delay times.

Here is one version. The 100 V is DC:

118964

Here's another, sequential flavor:

118965

ak
 
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AnalogKid

Well-Known Member
Most Helpful Member
Those are simple insulation-displacement sockets, with no brains inside. The big squares on the bottom slide off to reveal the contacts. Sliding on the cap presses the wires down into the tines to puncture the insulation. You can slide off all of the covers to confirm, but I agree with others that the five sockets probably are in direct parallel, and all light control is built into the bulbs.

ak
 

gophert

Well-Known Member
Most Helpful Member
This is such a simple solution. For years I thought this was a custom thing not realizing it might have been a kit. I've contacted the ebay sellers I could find. I'll transplant the electrical components if I can actually find a kit that works.

If not, i'll come back and try something like dr pepper and yourself are hinting at. The challenge of figuring that out would be more rewarding but maybe not as practical.

Cheers, folks!
If all of the lamps died at the same time, the wire under the wire nut may have simply oxidized and current flow slowed over the past 40 years. As resistance of the connection goes higher, so does temp and it eventually the heat, oxygen combination eventually oxides all the wire surface and it crapped out.

Try getting s new extension cord at the hardware store of the same thickness and wire gauge. Then open each black box and remove the cords without bending any of the small pins that are puncturing the cord insulation to make contact.

Then install the new section of cord by positioning it carefully between the two halves of each box and tightening the screws. The pins will either puncture the insulation or slice into the insulation.

That main power source is the only thing that would cause all to die at the same time.

If they stopped working one-by-one over the years, there is likely just an electrical contact issue at each box where the cord connects.

Cheers.
 

unclejed613

Well-Known Member
Most Helpful Member
Agreed; I've never seen them, but there is no reason thermal flasher lamps may not have been manufactured for 110/120V operation in the past.
i have seen some in the past, but they were in a holiday light string, and i think they were a series string, and so only one bulb in the string had the bimetallic switch inside it. occasionally there were parallel strings with flasher lamps (in a parallel string they're all 120V bulbs). the flashers in the parallel strings don't last very long, as some of the metal on the contacts eventually vaporizes, darkening the glass, and either the contacts eventually weld together (or burn open), or the filament fails from the continuous temperature cycling. incandescent flashing bulbs are usually very short-lived because there are so many possible failure modes.
 

narkeleptk

Member
i have seen some in the past, but they were in a holiday light string, and i think they were a series string, and so only one bulb in the string had the bimetallic switch inside it.
I just installed some old lights last Christmas that had these bulbs in them. You are correct that you only needed one in the string to blink all the lights in that series, and if this blinking contraption bulb thing was blown the whole series was out. I believe I had 4 total each controlling about 30 lights. Only one lasted the entire month.
 

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