Hello LF'ers,
04 June 2017
Marco, do you have the means of posting screen shots of the gare and
drain wave forms? I am always keen to see just what people consider
good and bad ones and a capture speaks a thousand words. Glad you seem
to be progressing with this now! Crossed fingers for you! :)
This is a capture of my latest amp on 52V @ about 18 Amps Gate is
lower trace, drain upper.
http://www.gatesgarth.com/capture.jpg
Best regards,
Chris 2E0ILY mailto:[email protected]
> Good morning LF &VLF :-)
> I had not a big choice among available cores for the driver xfmr.. and
> finally I choose a BN43-202 with a lower AL but higher cross section.
> Now the driver xfmr is wound 10T primary and 22T+22T of sec (it had to
> be 20T but the cutted wire allowed a couple of turns more ;-) )
> Now have provided much confortable test points for the gates too.
> So I wired everything and replaced the original 150µH coil with
> 4x2200pF in the output tank and have again available(but not yet
> connected) the 25T for the guard circuit.
> the gates now are switched with a square wave (a bit smoothed in the
> rising side) swinging from + 20 to -10 V with respect to ground.
> The tx is running since about half an hour at 50Vdc and only the dummy
> load is warming a bit.
> With 7T/19T xfmr on the output it is puring 35Wout with 45W input
> Unfortunately I cannot rise the supply continously from 50V to the
> final 180V.. so will let it to be used to eat 50V and later give 180V
> Cross your fingers!
> Marco IK1HSS
--
Best regards,
Chris mailto:[email protected]
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