TNC 145 - Electronic Part Identification

[Joe_Leen]

Hey all,

I'm currently dismatling my TNC145 controller and trying to identify an electronic part. Basically it's mounted on the first board on the top right hand corner. It resembles a fuse in size and shape but has a red graduated scale along it's body, going from zero to ten. Does anyone know what this is ? Haven't seen one before.

I'm currently drawing out a circuit diagram for the board, until I find the fault - Heidenhain only seem to make the block diagrams available - no schematics about ?

Thanks,

Joe

[Mike Woo]

Hi Jo
I would be greatfull of your diagrams when you are done. I am trying to trace a power supply board problem but like you am having trouble getting info on the circuits.
Cheers and good luck.

[jmelson]

Originally Posted by Joe_Leen Hey all, I'm currently dismatling my TNC145 controller and trying to identify an electronic part. Basically it's mounted on the first board on the top right hand corner. It resembles a fuse in size and shape but has a red graduated scale along it's body, going from zero to ten. Does anyone know what this is ? Haven't seen one before. Joe

I suspect it is a running time meter. They have a glass tube with some electrolyte and mercury in it, and a small current causes the mercury to move from one end to the other of the tube. It will have a resistor in series with it, and be connected across a power supply. If you reverse it, the line will start moving the opposite direction.

Jon

[dreammstr6]

Jon is correct it is a run time counter for the display. Tektronix also uses those on the o-scopes and spectrum analyzers for service purposes.