[time-nuts] HP5061A tube question

corby d dawson cdelect at juno.com
Mon Jun 30 12:31:34 EDT 2008


The tube is in a vacuum so the ovens heat only has roundabout physical
paths to get to the outer case. If the tube feels warm at all at both
ends the oven and hotwire are  probably working OK.

If you have a T type thermocouple temperature meter you can connect it to
the copper and silver wires coming out of the potting and measure the
ovens temperature directly.

Another way is to let the unit warm up for an hour or so, remove power,
and then quickly remove the tubes connection to J16.
Then hook an ohmeter from pin 9 of the removed cable to chassis ground.

This is measuring the oven thermistor value and should be close to the
value on the tubes label.

If that is OK then I'd recommend performing the low frequency test
outlined in the manual. This will help determine if the tube is gone or

Whereabouts are you located?

Corby Dawson
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