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MrBungle · 13th Jan 2018, 10:03 am

Just a point on spooky readings on FET GDOs; I’m wondering if this is the same thing I had with my VFO based on a 2n4416. I found after looking closely with the scope is that it would periodically break into bursts of oscillation. So it was oscillating at the fundamental and a high frequency that was modulated by a third. Couldn’t see it on an analogue scope but could on a digital. Ferrite from a broken tek scope slipped over gate stopped that but I’m not sure that would scale to a wide band oscillator like a GDO without tailing off.

13th Jan 2018, 10:03 am	#39
MrBungle Dekatron Join Date: Jun 2016 Location: London, UK. Posts: 3,687	Re: The Best GDO Ever Made? Just a point on spooky readings on FET GDOs; I’m wondering if this is the same thing I had with my VFO based on a 2n4416. I found after looking closely with the scope is that it would periodically break into bursts of oscillation. So it was oscillating at the fundamental and a high frequency that was modulated by a third. Couldn’t see it on an analogue scope but could on a digital. Ferrite from a broken tek scope slipped over gate stopped that but I’m not sure that would scale to a wide band oscillator like a GDO without tailing off.