Follow up for the odd member who might be interested.
Zuludog kindly sent me the meters and with varying degrees of brute force and ignorance opened up the cases.
On the plus side, they are very neat and tidy on the inside with all the electronics and stuff nicely mounted on custom printed circuit boards. Interestingly, they all use variants of the same Texas Instruments micro-processor chip despite being from different manufacturers and different vintages. I'm told this particular chip is designed for low power consumption (needed in a meter running off small batteries) and is in common use for this type of application. They each have different types of screen and I suspect most of the circuitry outside the main chip is there to run them. As far as I can see they, like my accucheck meter, all use six contacts on the test strip. My guess from that is that they all measure a change in resistance in the test strip when blood is applied. How that is turned into a blood glucose measurement is a mystery hiding somewhere in the microprocessor. It would need someone more knowledgable than me to tease out what is going on in there.
Sadly, nothing inside is salvageable for reuse so it is landfill for the debris.
