The connectors arrived today to tie the MCU board tothe filter board, and the counter is counting! I am still running the HV supply on a separate power supply until the PCBs show up for the power filter/pre-regulator. Power consumption is about 1/2W total.

The software is working well enough to get coherent log files through the serial port. Right now, I am running the UART at logic level out to an external logic level UART board until I decide on RS232 or RS422 for the external interface.

Initial testing on the bench in my shop is showing about 20 - 36 counts/minute and parking an envelope of 35 year old 2% thoriated tungsten TIG electrodes a couple of inches from the tube triples that number.

So far, so good.

I also started on the Linux software that will monitor the serial data output stream and log it. That is coming together slowly, as I am still deciding what I want it to do...