Fixing tube broked pins

[catalin gramada]

This is how some tech fixed broked pins of the tube in comunist period when there was no chance to found any replacement on the market.

[Mick Bailey]

It looks like a real act of desperation and it makes you wonder what the story is behind that.

[Jon Snell]

I see safety was in mind, as they used safety pins.

[Mick Bailey]

You forget to add "I'm here all week, try the Veal."

[vintagekiki]

Tube time machine

[Pedro Vecino]

A while ago I bought a few 12BH7s marketed by National and found this:



Each one has a circular printed circuit with which it exchanges the connection of certain pins. The original mark on the glass is erased with acid. After doing some research I came to the conclusion that the original tubes are 6463 G.E. A tube used for computers. They work in a similar way to the 12BH7.

[g1]

This is how some tech fixed broked pins of the tube in comunist period when there was no chance to found any replacement on the market.

I don't understand this fix. If the pins were broken, how does pulling them up toward the top provide any strain relief? Was there a strap running around the circumference of the tube?

[Pedro Vecino]

The rising metal frame that makes up the extensions (4) is shaped like the base of the tube. Presumably those pins were accidentally cut off. It seems that the wires going upwards are a fulcrum to obtain mechanical strength when soldering the added angled pins with the rest of the tube pin between them.

[Helmholtz]

I don't understand the repair either.

[g1]

The rising metal frame that makes up the extensions (4) is shaped like the base of the tube. Presumably those pins were accidentally cut off. It seems that the wires going upwards are a fulcrum to obtain mechanical strength when soldering the added angled pins with the rest of the tube pin between them.

The only advantage I can see is maybe it helps support the new pin extensions when the tube is being pulled from it's socket?
Perhaps some wishful thinking on the part of the repairman, looking ahead at a long extended life for this 'refurbished' tube.

[vintagekiki]

... fixed broked pins...

The tube broken points, make contact with the new pin, similar as contact point at 775 CPU socket.

[Pedro Vecino]

The only advantage I can see is maybe it helps support the new pin extensions when the tube is being pulled from it's socket?
Perhaps some wishful thinking on the part of the repairman, looking ahead at a long extended life for this 'refurbished' tube.

I think that a direct solder of a wire on a pin cut practically flush without any other type of contribution in terms of mass could not even support its insertion in the socket.

[drewl]

Hey, sometimes you have to do what you can if no replacement s are available.

Not that this qualifies.

[Jon Snell]

The tube broken points, make contact with the new pin, similar as contact point at 775 CPU socket.

But steel pins on valves are not gold plated like BGA CPUs. Poor connection at best.
Don't break the pins in the first place is the best option, in my view.

[J M Fahey]

Why not junk broken tubes and insert something else?

Tubes ARE available,and always were.
Some particular model could have disappeared but tons others can more or less do the same, LOTS of interchangeability.

If needed, rewire *sockets* and leave tubes alone.