Tek 310A sillyscope

From: John Lawson <jpl15_at_panix.com>
Date: Mon Nov 25 18:58:00 2002

  A manual for your oscilloscope can be found at: www.w7fg.com for $25
bux.

  I also second Tony Duell that it is unlikely the power transformer would
have failed, especially in such a small and lightly-loaded device.

  But locating and removing the B+ secondary leads from the rectifier
components (probably selenum in that vintage of a scope) will begin to
isolate the problem. Also be very aware that shorted and/or arcing
selenium rectifiers produce copious amounts of deadly (and stinky)
hydrogen sulfide gas. (The same gas that makes rotten eggs so odiferous)

  Be thankful that it's a catasrophic, fuse-blowing-instantly type of
fault - which will have a definite unmistakable cause and a hopefully easy
remedy. But isolate the HV leads first, then the filament leads if the
fuse still blows.

  Also verify that the proper value fuse is installed. I chased my tail
all over the workbench trying to find the 'problem' in a Hewlett Packard
VHF signal generator, only to realize that the fuse holder was clearly
marked "4A" and someone had put a 1-1/2A fuse in it, which, of course,
blew as soon as the voltage hit the tubes - and which I dutifully kept
replacing with one of the same value as the blown one as I methodically
and carefully 'troubleshot' the damn thing.

   D'OH!!!!


  Cheers

John
Received on Mon Nov 25 2002 - 18:58:00 GMT