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Jolly 7 · 13th Feb 2019, 7:44 pm

I recently received a batch of BF981 mosfets and need to establish that they are working.
I found the following instructions on the net,; can anyone please advise if they are valid tests for dual gate mosfets ? Thanks.

Firstly, measure the resistance between both gates (connect them together) and drain and source, the resistance should be near infinite, >100M.

Secondly connect both of the gates to the drain. Measure the resistance between the drain (meter positive) and the source (meter negative), it should be under 1k.

Finally connect the 5V supply's positive to the source and negative to the gates. Measure the source - drain resistance, it should be much higher than the previous measurement >1M.

13th Feb 2019, 7:44 pm	#1
Jolly 7 Octode Join Date: Feb 2018 Location: Southampton, Hampshire, UK. Posts: 1,063	Testing a dual gate mosfet I recently received a batch of BF981 mosfets and need to establish that they are working. I found the following instructions on the net,; can anyone please advise if they are valid tests for dual gate mosfets ? Thanks. Firstly, measure the resistance between both gates (connect them together) and drain and source, the resistance should be near infinite, >100M. Secondly connect both of the gates to the drain. Measure the resistance between the drain (meter positive) and the source (meter negative), it should be under 1k. Finally connect the 5V supply's positive to the source and negative to the gates. Measure the source - drain resistance, it should be much higher than the previous measurement >1M.