Ice Tube converter issue

[Mundoo]

Tests in order as before:

10.49v 7805 input voltage
5.00v 7805 output
18.74v VFD booster voltage (this kept going down while I had the probes in place, is this normal?)

Looks like the 7805 is outputting the proper voltage! Geez, what a difference a battery makes, eh?

[adafruit_support_bill]

Are these measurements with the tube installed?

[Mundoo]

They are without the tube installed.

[adafruit_support_bill]

What voltages do you measure on each of the three pins of Q3?

[Mundoo]

Across 1 and 3, it measures 1.0 volts. Across 1 and 2, I get 1.6 volts. Across 2 and 3, I get nothing.

The tube is not installed.

[adafruit_support_bill]

Sorry, I meant measure the voltage of each pin relative to ground.

[Mundoo]

Okay, measured using ground = the flat bit of the 7805:

Pin 1: 4.7v
Pin 2: 3.0v
Pin 3: 3.0v

[adafruit_support_bill]

Now measure the voltage on pin 13 of the Atmega chip.
And, just to double check, the voltage on pin 5. (should be the same as pin 2 of Q3)

[Mundoo]

Pin 13: 1.14v
Pin 5: 2.94v

I used this pin-out sheet:

[adafruit]

why isnt the 22 ohm resistor installed?

[Mundoo]

... you know I have no idea, I'll go install it.

Be right back :3

Edit: Okay, it's installed now. I'll get those voltages again in a minute.

[Mundoo]

Pin 13: 1.14v
Pin 5: 2.95v

Tried booting it with the tube installed, still nothing :/

[adafruit_support_bill]

On Q3, carefully short pin-1 to pin-3 and see if the tube lights.

[Mundoo]

Okay, I shorted pins 1 and 3 on Q3. Still nothing. It beeped, but no display.

I tried it 3 times, but now it's not beeping and there's two dim orange lines running horizontally across the display on the inside. It does it even if I'm not shorting Q3 :/

[adafruit_support_bill]

Q3 controls the filament voltage in the tube as well as power to the VFD chip. The missing 22 ohm resistor was preventing the filament voltage from getting to the tube, but it seems we have other problems as well.

What voltage to you see on the 3 pins of Q3 now?