Re: Software support Request for Full QSK BITX40
Gary,toggle quoted messageShow quoted text
Simulating just the IRF510 and T7, minimal load, driving the gate hard with a 0-10v square wave,
I see spikes to several kV as current through the IRF510 shuts off, but only if I slow the square wave down enough.
The simulation gets kind of weird with a load of 10k ohms or more
At 7mhz the IRF510 stays on, even in the troughs, even though the gate pin goes to zero volts.
I haven't looked at the model for the IRF510, but all it would take is resistance going into the gate
and miller capacitance from drain to gate to account for this.
So T7 does indeed behave like a flyback transformer at slow speeds, but at 7mhz the IRF510
stays on to where that coil current always has somewhere to go, T7 behaves more like a forward transformer.
On Wed, Jan 31, 2018 at 01:26 pm, Jerry Gaffke wrote:
With no load at the antenna port, the simulation shows an IRF510 drain current that stays near the quiescent 100ma