On Apr 4, 9:58*am, ken scharf wrote:
JIMMIE wrote:
I have a Systron Donner frequency counter that uses Nixie tubes. The
counter works fine but I am forever replacing the Nixie drivers
74141s. I started to use it this AM an one was out. Is there a
replacement for the 74141, I couldnt find one, or is there a circuit I
could build on a DIP header to replace them. I could probably design
one but I wanted something tried an tested as I dont want to put my
counter board at more risk than I have to.

Jimmie

The chips are failing for one of two reasons, over voltage or over
current. *Try reducing the supply voltage to the minimum that will light
the nixies. *Also try heatsinking the 74141's. *They do make clip on
heatsinks for dip packages, but you can just superglue scraps of
aluminum to the top of the chips.

This has been a problem on two different Systron Donner counters I own
and one we used at work years ago. It was such a regular thing at work
we added sockets to facilitate replacing the chips. I have done
likewise to mine but only as the chips failed. There are still a
couple of origonal chips in it. Mycounters are model 6153. I have
never had a schematic or manual for them and
This makes maintaining them a little difficult but having two of them
helps allowing me to compare signals and swap boards to help isolate
problems. If anyone has a schematic I would greatly appreciate it.

Jimmie