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also I need an EF92 for an old Sky king radio ...Willy
As to germanium transistors and diodes (I noticed somebody saying the are still in production - BUT they can't be found) are long dead is that newer tech works a lot better and has much better reliability.Silicium is really starting to be yesterday's tech now in Power Conversion - AC/DC, DC/DC and DC/AC as Silicon Carbide (SiC) and Gallium Nitride (GaN) can cope with much higher Power, Voltage and Ampere, with much higher efficiency and reliability.
Just as well we need things like governors and ignition systems to allow us to combine our interests.
I know that the voltage generated in the coil is dependent on the rate of change of current, so switching time is obviously important. But how did you decide on your target of 100 nS?
Germanium diodes are made by American Microsemiconductor:https://www.americanmicrosemi.com/tutorial/germanium-diodes/
I can't see silicon disappearing any time soon. I've used silicon carbide devices for a high temperature (>200°C) inverter, but the devices are expensive if you don't need the high temperature capability. Gallium nitride is good for power RF devices as it has a very high electron mobility, but it is also a high bandgap material so the forward voltage across a junction is high - can't see that being an advantage in general power devices. Ultimately engineering is all about money and silicon devices are relatively cheap.
I do not agree with your interpretation of Copyright Jason, each case must be considered in context. In the future if any one has any concerns about a post could they please use the "Report to Moderators" feature, rather than taking it upon themselves to police our forum. Thank you.JoHi Jo, nothing do with copywrite and just wondered if you recognise the castings for this ancient table engine that someone gave me a photo of ...it was in a derelict house that someone visited just before it was being demolished ...no further details however ....Thankswilly