What to do when the a part is no longer available? Whilst visiting one of our customers for another issue, they asked a random question that we knew was the end of a much longer thread.
“Can you get resistors?” – resistors are an electronic component that you really wouldn’t ask for unless you knew exactly what you were doing, and if you did, you would know where to buy them.
We can get resistors, but we needed to explore what it was for.
They had several pieces of equipment used to monitor breathing of a sedated animal, and this had a sensor on a wire that kept getting damaged due to it being quite delicate. This part had now been discontinued.
They were faced with throwing 4 pieces of working equipment away because they could not get a tiny spare part. Replacing these would cost thousands of pounds, so we set about finding a solution.
There was the option of a quick fix. Solder a new thermistor (not resistor) on to the end, but that fix would probably only work once and carried a risk that any failure or breakage risked being inhaled by the animal.
We needed to reverse engineer the whole thing. We took some very accurate measurements which gave us the blueprint for the body. After a number of prototypes, we had a solution for the body.

The thermistor is the size of a grain of rice, so there was no chance of getting a part number. We took electrical measurements to ascertain its specification, and ordered a batch.

The connection was a simple RCA or phono connector, but we needed the right combination of panel mount and solder tabs. We settled on one, and ordered those also.

After some delicate soldering and construction, we had a working part.

The customer was delighted, and we had a part that could be sold to anyone else facing the same issue.
Reverse engineering and building bespoke is time consuming and expensive, but in can be done.
If you have a problem you just cannot find a solution for, get in contract. Our ability to work across engineering, electronics, and technology is second to none and we love making the impossible, possible.