Resistors; Check The Tubes - Nixie Clock ITS1A Manual

5. Secure the display board to the brackets with the nuts and bolts provide.
6. Solder the socket to the main board – making sure it is flush with the board.
7. Solder the right-angled header to the display board.
8. Un-bolt the display board and remove it for the following steps.

Resistors

Solder the 47K resistors (Display: R1-R4) into place. You can choose whether you want these on the
front or the back.

Check the Tubes

Before you solder in the tubes, you should check that they work. Removing a broken tube is not easy.
There are a couple of things that can be checked before they are soldered in.
The first is to check that there are no shorts between the pins.
The second is to check that the tubes contain neon. The easiest way to do this is to hold them next to a
plasma globe, or anything that generates a few KV. Plasma globes are fairly cheap these days. Check
Amazon, ebay, Walmart, a toy store, a party store etc. etc. If there is neon in the tube, you should see an
orange glow inside it like the image on the left. The image on the right is of a nixie tube with no neon in
it. There is no orange glow inside it:
ITS1A CLOCK
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