Tonywoodside replication PCB
Webmug replication
As we can see the duty cycle to the TIP120 transistor is not 50%, this happens when the transistors in the driver circuit are not properly biased!
Also the pickup from the TIP120 signal has not 50% duty cycle.
The output from the PLL has 50% duty cycle.
I used the variable resistor values to get the same output as Tonywoodside. The values from Dynodon didn't work at all.
Any ideas what resistor values are needed? The current going into the primary coil should be high for the type of wire used (30AWG).
So the TIP120 is biased.
Stan used a 2N2222 (Ic 800 mA) and two 2N3906 (Ic 200 mA) transistors. The 4046 PLL is powered by 12V and pulsing at the resistor input network to the base of the 2N3906 (emitter 12V) etc.
Br,
Webmug
