Re: DB6NT sequencer


Robin Szemeti - G1YFG
 

Daft question ... have you got a back EMF diode on the relay coil?  You need something to catch the pulse when FET opens and the coil current collapses.  You could try slowing the gate rase/fall times to limit the di/dt in the coil.

On Tue, 23 Mar 2021 at 10:20, Graham - G3YJR <g3yjr@...> wrote:
I wonder if you might have done this?: I put an indicator LED/resistor across the switching FET to indicate the state and I was surprised to find that the indicator LED passed just enough current to hold the relay on. A higher resistance and a lower-drain/brighter LED solved the problem.

73 Graham


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Robin Szemeti - G1YFG

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