Hi,

I wondered if anyone could give any advice.
I'm currently making a Nixie clock and as some may know they run a quite a high voltage (170vdc).
I'm making it from a 'kit' so everything is supplied.
The build instructions are here http://www.pvelectronics.co.uk/kits/qtcplus/QtcPlusV3.pdf
I've made up the low voltage part and tested and got the correct voltage, then made up the high voltage part and dont get any more than about 11.4v from it.
I've emailed the suppliers and they actually replied straight away on boxing day! Just asked for some voltage readings and photos and had nothing since (I assume they'll get back to me after the new year, hopefully!).
But is there anything else I can try/test in the meantime? The wiring diagrams and troubleshooting they gave are at the end of the PDF linked above.
I've triple checked orientation of diodes and capacitors and that the resistors are the correct value. Along with checking all the soldered joints for any sort of bleed between the points or poorly soldered points but cant see anything!

Cheers for any help.

Mark

 

They will not be able to go any further until you send them the readings the requested. If they have not requested a picture of the waveform on the gate of Q1 I suggest sending them that as well. If you can't photograph the oscilloscope trace then just give them the frequency and duty cycle information. You could also post the information on the forum.

Les.

 

Simple:
You are seeing the input voltage minus a forward diode drop.

The PWM controller is not oscillating!

 

Post the voltages at these locations:


HV power supply section for reference:


EDIT: Added IC2