Tube PWM... I finally got around to it

[Tim Williams]

http://webpages.charter.net/dawill/tmoranwms/Elec_Compound.html

The top part is off topic; scroll down to around the bottom for the circuit
and description.

I haven't done the output stage yet; it's next.

Tim

 

[Tim Wescott]

http://webpages.charter.net/dawill/tmoranwms/Elec_Compound.html

The top part is off topic; scroll down to around the bottom for the circuit
and description.

I haven't done the output stage yet; it's next.

Tim

You will find, I think, some pretty significant nonlinearities in the
output stage due to discontinuous conduction.

But please, don't let that stop you, it's an interesting notion.

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html

 

[Tim Shoppa]

http://webpages.charter.net/dawill/tmoranwms/Elec_Compound.html

The top part is off topic; scroll down to around the bottom for the circuit
and description.

I haven't done the output stage yet; it's next.

Tim

Very interesting. One note based on me using those Heath scopes
decades ago: the little nubs you are seeing are probably related to
the scope's triggering circuitry either intentionally or
unintentionally screwing up the horizontal sweep. (It is an injection-
locked oscillator after all). IIRC if you move the trigger sensitivity
up and down then the nubs move too. I never knew if this was
intentional or not (after all many of the expensive scopes had an
"intensify trigger point" option, maybe Heath had a cheaper way of
doing it!)

Tim.