Kudos, you're right. Quite a rare beast.I think first symbol is a feedthrough filter.
I used them frequently when I built filters and such (basically anything in a sealed metal box) as an R&D tech.I searched for 'capacitor with wire through middle' and got one hit on a 5y old post on EE StackExchange referencing the same symbol.
Thanks for replyWelcome to AAC.
The bottom symbol is similar to what one sees for neon bulbs:
View attachment 209600
Hello, I have found these 2 symbols in electronic scheme and I can't identify them
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Thanks for your help
Thank you for replying. I have found this symbol in a transducer conditioning signal circuitI concur on the neon, its a variation on the theme. Can also be a gas discharge surge arrester.
The first symbol is most likely a variation on a (RF) resonant filter, most usually a ceramic, crystal or piezoelectric type, as would possibly be found in the IF strip of a miniature radio receiver as an alternative to inductive filters. The symbol usually only has 3 ports, in, out and ground, even though the actual device will often have 4 wires (in/gnd, out/gnd).
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