Lidmotor's Penny circuit help needed.

[TinselKoala]

Well, with my build using the MPSA18 transistor, I decided to put the board together first without the 1.2 nF cap, although I have the board drilled for it. I was going to wait until I had baseline data without it, before installing on the board. But it gave ambiguous results when I had the thing in its first build, the "deadbug" construction. When I get the BC337 transistors I'll be able to test the 1.2 nF cap properly.

So yes, for the rotated transistor test, I didn't use the 1.2 nF cap.


It is still oscillating. The battery voltage is down to 334 mV, the collector peaks are 1320 mV and the frequency is 529 kHz. Scope reports "average" collector voltage 330-340 mV.


Do you have a 2sc710 in the sim?

[Legalizeshemp420]

It does not but it does have the MPS line up (2sc/2sd are rare in it and I have had zero luck making my own even when I do exactly as it the tutorials say with datasheet in hand).

For it to have dropped only 3000 micro volts in this length of time it is hardly using any current to sustain its oscillation but I am surprised it is oscillating without a load too.

[TinselKoala]

Sorry, I had the "rotation" test described wrong. But your schematic is wrong too! Your LEDs are now disconnected!
Please try the original circuit, but just hook the transistor as follows:

Base of transistor >  where the collector used to connect.
Emitter of transistor > leave in place
Collector of transistor > where the base used to connect.

So you just swap collector and base, don't change anything else from the original. Try with and without the 1.2 nF cap.

[Legalizeshemp420]

Naw, my screenshot chopped off the ground but it was there only hidden.

Let me run up the new stuff you want.

[Legalizeshemp420]

Same results with and without the cap.