So this means that after unscrewing the tube with only head left, a cell with wires coming from the + and - ends be connected to the center and thread area while someone is pressing the switch?
When you have your light, and the head unscrewed, look first at the driver to make sure driver is sitting level and not damaged. If it is not level, it could prevent the battery tube’s negative end from making proper contact with the driver’s negative contact ring.
I have not yet tested Streamer’s suggestion, but photo below shows the non-working head at the left. On the not-malfunctioning right EA11 head, there is that white blob on the 12 o clock position, near the edge of the outer, negative ring.
I can not tell from pic of the head on left, but is the positive contact on driver flattened slightly or squashed? Has the driver been pushed lower in the head?
This would account for contact problem and light not working,
Remember, the end of battery tube must contact negative ring on driver. So,I think your driver MAY be pushed down slightly not allowing end of tube to make good contact with negative ring.
The head seems to be OK from your battery holder test. :+1:
I wonder why it’s there in my photo, but re-checking it again now there’s no lump of solder…perhaps it was just a reflection or something created by the camera phone.
So now that a test was performed as suggested by Streamer and the light worked, does it mean that the driver and switch are still good but only a ground problem?
Perhaps the light fell head first, jarring the pcb and moved it forward, out of reach of the tube now?
If so, what then is the next move? My non-modder’s mind tells me to put a conductive spacer between the tube and the (-) negative ring… is this a workable and safe idea?
Yes. Make a circle of appropriately sized wire to fit over the drivers negative ring so tube can make contact. But be very careful as to avoid a short.
HINT: Sometimes a key-ring of right diameter will fit perfectly over negative ring :student:
Got it.
I have some small brass shim sheets to make a ring, though I cannot find it now… perhaps this will be enough to make contact.
Edit: I tried a loop of soldering lead and it worked!
Now my next question is: If I fabricate a brass shim instead of the soldering lead, will it not be dangerous for the shim if it ‘bites’ into the anodized, threaded part of the head?
No danger. The shim your making will simply be an extension of the negative contact. The entire body of the flashlight is also negative, though it is non-conductive where the anodizing is present. Therefore if the shim bites the anodizing and makes contact with bare threads then there will be no difference in potentials (negative on negative).