micr0man
Member
Hi,
I do not use this forum very often, and mostly just hide in the chat, but I have come across a problem which I can't figure out what the problem is, so I'm hoping maybe somebody could give me a bit of help. I have a few IN9 bar-graph nixie tubes sitting on my desk which I decided to attempt to interface. I created a HV supply, from stepping down the 230v mains to 50v, rectified to ~71V and then doubled using a voltage doubler to 141V. The datasheet says that the max firing voltage is 140V, but due to the low current I am getting more like 160V on the transformer output which is good.
I am controlling the current with a transistor giving me a variable current of around 0-20mA, but here is where my problem lies. For some reason, I am not getting a full bottom to top scale on the tube, even when the multimeter is saying up to about 19mA. At about 12mA, the tube is just getting brighter as is expected to do when at the top of the scale. I have tried multiple tubes with the same outcome, so I was wondering if I am doing anything majorly wrong.
I know quite a few of you dislike the java circuit simulator, but I have here a basic simulation of the circuit and it seems to work well enough: Falstad Circuit Simulator - Nixie Control
This is the schematic:
**broken link removed**
It could be the worst video you've ever seen, without any explanation but you can quickly see what is happening in this video:
Thanks again for the help anybody can give,
Dave
I do not use this forum very often, and mostly just hide in the chat, but I have come across a problem which I can't figure out what the problem is, so I'm hoping maybe somebody could give me a bit of help. I have a few IN9 bar-graph nixie tubes sitting on my desk which I decided to attempt to interface. I created a HV supply, from stepping down the 230v mains to 50v, rectified to ~71V and then doubled using a voltage doubler to 141V. The datasheet says that the max firing voltage is 140V, but due to the low current I am getting more like 160V on the transformer output which is good.
I am controlling the current with a transistor giving me a variable current of around 0-20mA, but here is where my problem lies. For some reason, I am not getting a full bottom to top scale on the tube, even when the multimeter is saying up to about 19mA. At about 12mA, the tube is just getting brighter as is expected to do when at the top of the scale. I have tried multiple tubes with the same outcome, so I was wondering if I am doing anything majorly wrong.
I know quite a few of you dislike the java circuit simulator, but I have here a basic simulation of the circuit and it seems to work well enough: Falstad Circuit Simulator - Nixie Control
This is the schematic:
**broken link removed**
It could be the worst video you've ever seen, without any explanation but you can quickly see what is happening in this video:
Thanks again for the help anybody can give,
Dave