I’m hoping for suggestions — to fill this lamp out and drive the chosen emitters.
I haven’t worked with COB emitters before. I know they get very hot and have to be screwed/glued to a significant heat sink.
But I haven’t figured out what to get, yet. All I know is what I described above.
This has one of the pair of AC black wires going directly to one of the two screw connectors side by side on one end of the fluorescent tube.
The second of that pair of screws on that end of the lamp is another black wire going to the ballast.
The other side of the ballast has another black wire that goes to the switch (usual red and white pair of buttons) and from the switch back to the AC.
And the AC isn’t polarized.
The pair of white wires from the ballast go together to the pair of screws side by side on the other end of the fluorescent tube.
I’ve never seen that wiring setup before… Took it apart to make sure that’s what I was seeing.
I guess the 110v on one end heats up the tube, and the pair of connectors on the other end has the high voltage to excite the light.
Seems weird.
Could you just get a 12V dc wall-wart rated at 1500mA and power one of those COB strips from DX with that? Or, get a 12V transformer and a regulator and wire them into the base? Or, choice three, install batteries in the base, and replace/recharge them as needed.
Put in a chroma50,design50,vitalite,or othe 5000k high cri tube.
it sounds like it could be a very early example and worth preserving.
I did one for dc but it was essentialy scrap metal when I got it.
all my solar buddies loved it so much I did a ton of 50,s-60,s units up.
if mine were not a total wreck I would have left it original.
it had a very early side printed ge tube.one of the very first fluorescents.
OK, I like the idea of a modern multiple phosphor lamp. It’s worth trying to see if lamps sold today will work with this setup.
I find cool white 15 watt 18-inch T8s advertised, anyhow.
Looking at Sam’s Repair FAQ, which has ASCII-art diagrams of wiring, none quite match this one but some are close.
One diagrammed circuit he shows connects the neutral side of the house wiring to one end of the fluorescent.
His diagrams all include a starter separate from the ballast — I’d guess that’s a newer design than what I have here.
The wiring on the lamp I have was nonpolarized, as I mentioned (and old, cracking rubber over paper insulation).
No protection on it where it goes through a hole in the base either, just a bit of old cloth tape on the inside to keep it from pulling out.
I doubt the actual plug was original, it looks like 1950s-60s typical plastic.
So I want to put a 3-wire cord and a strain relief and properly ground the case, though a historian would cringe I suppose.
But I”ll try it with the original setup other than that and see what we get.
(I’m not sure what a “simple choke” is but if it’s an “ordinary inductor” see the caution quoted below)
I appreciate it’s possibly of some historical interest; I haven’t torn it up yet. I pulled off the old (likely original) 110v wire (which was badly cracked rubber over disintegrating paper wrapped wires, and connected to the inside wires with sticky black cloth tape — as it had a non-polarized plug and seemed just plain unsafe).
The diagrams I found at the Electronics Repair FAQ show some old lamp wiring diagrams that do route one side — neutral side— of the 110v directly to one end of the fluorescent, as is done on this lamp. But nothing that exactly matches. I’ll work up an ASCII Art diagram of this one along with pictures. As time allows.
So I’ll put on a grounded wire, connect the neutral to the wire that goes to the lamp and the hot to the wire that goes to the black box, and — um — see what happens.
The Electronics Repair FAQ does say:
GE’s website says all their older ballasts include a PCB capacitor, but they could just be being “safe rather than sorry” or not go back far enough. Or maybe this isn’t technically a “ballast”…
