Graham Gunderson's Energy conference presentation Most impressive and mysterious

[TinselKoala]

Since the U3 clock is entirely independent of the clock pulses generated by the U5-U7 system it's hard for me to understand how they could maintain a precise relationship. Perhaps the timing drift between these two independent pulse generating systems is why Gunderson's results are not consistent over time or from trial to trial.

A microprocessor control system would certainly make synchronization among all the necessary pulse timings more precise.

[Spokane1]

Since the U3 clock is entirely independent of the clock pulses generated by the U5-U7 system it's hard for me to understand how they could maintain a precise relationship. Perhaps the timing drift between these two independent pulse generating systems is why Gunderson's results are not consistent over time or from trial to trial.

A microprocessor control system would certainly make synchronization among all the necessary pulse timings more precise.

Dear TK,

I agree with you. I probably missed a connection or small jumper wire some where.

Spokane1

[Farmhand]

I'm reposting Gotoluc's scopeshot along with the Gunderson scopeshot. As you can see Luc's shot is virtually identical to the "input" traces on Gunderson's shot.

And he achieved it with a much simpler circuit (but using a FG for the clock instead of making an oscillator out of logic chips.)

Now, I'd like to see what Luc can get for an output!

Umm, isn't Gotoluc's output 4.07 volts across a 20 Ohm resister ?

Doesn't that work out to about 0.8 Watt output ?

Input says 1.97 VA but what is the input in Watts ?

I'm assuming he has no synchronous rectification. Is he just using a FWBR.

[TinselKoala]

The 74HC123s do not oscillate on their own. Apparently there must be an input from an external clock for the system to work. I supplied a clock signal from one of my function generators to Pin 10 of U7. I could not get it to work with a signal from the 556 circuit that I tested earlier. The result is shown in the screenshot below.

The CH1 Yellow trace is the Pin 13 output of U5 which goes to the Synchronous Diode. The CH2 Light Blue and CH3 Purple (Cyan and Magenta?) traces are the complimentary outputs of the 7414 U8 which go to the H-bridge. The CH4 Dark Blue trace is the input from my FG to Pin 10 of U7.

The two pots on U5 control the Yellow trace pulse width and pulse delay. One of the pots on U7 controls the pulse width of the two complimentary outputs of U8 to the H-bridge. I couldn't see any effect of the other pot on U7 but that may be due to where I'm injecting the clock signal.

[k4zep]

The 74HC123s do not oscillate on their own. Apparently there must be an input from an external clock for the system to work. I supplied a clock signal from one of my function generators to Pin 10 of U7. I could not get it to work with a signal from the 556 circuit that I tested earlier. The result is shown in the screenshot below.

The CH1 Yellow trace is the Pin 13 output of U5 which goes to the Synchronous Diode. The CH2 Light Blue and CH3 Purple (Cyan and Magenta?) traces are the complimentary outputs of the 7414 U8 which go to the H-bridge. The CH4 Dark Blue trace is the input from my FG to Pin 10 of U7.

The two pots on U5 control the Yellow trace pulse width and pulse delay. One of the pots on U7 controls the pulse width of the two complimentary outputs of U8 to the H-bridge. I couldn't see any effect of the other pot on U7 but that may be due to where I'm injecting the clock signal.

Morning TK,

Try this: