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Biggles · 14th Feb 2019, 9:47 pm

I think the 455KHz oscillator could be pressed into use if you have a scope to compare the input and output waveform levels to check gain. A lot of dual gate mosfets are designed to operate at VHF/UHF but it would be very tricky to test them dynamically at those sorts of frequencies without an appropriate test circuit and some good test gear. Substitution in the front end of a VHF receiver would be one way but of course that will mean soldering and possible cropping of leads to make them fit so the DC testing is going to be the quick and easy option.

14th Feb 2019, 9:47 pm	#9
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Re: Testing a dual gate mosfet I think the 455KHz oscillator could be pressed into use if you have a scope to compare the input and output waveform levels to check gain. A lot of dual gate mosfets are designed to operate at VHF/UHF but it would be very tricky to test them dynamically at those sorts of frequencies without an appropriate test circuit and some good test gear. Substitution in the front end of a VHF receiver would be one way but of course that will mean soldering and possible cropping of leads to make them fit so the DC testing is going to be the quick and easy option.