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6AL5W-Martin · 2nd Jan 2016, 4:13 pm

hello Dave,
1.) check -150V
first of all you have to check the voltages from the PSU, always !
And always at first the -150 volts bec. this is used for reference to provide all other voltages in that PSU. If there is another then -150V , there is a pot to adjust it, and if this will not help write here again. Adjust the -150V very exactly, <1%

Tell us if you have a running scope there, if yes check the ripple on the -150V also,
if you have a high voltage test head for the multimeter or VTVM?
if you have a valves tester?

2.) check all other voltages from the PSU

+100V
+225V
+350V
+500V

if possible give us a screen picture and of coarse the results of your test.

greetings from germany
Martin

! take care, the PSU is very powerful, life dangerous voltages !

2nd Jan 2016, 4:13 pm	#11
6AL5W-Martin Hexode Join Date: Nov 2006 Location: Biedenkopf, [Hessen], Germany. Posts: 425	Re: Tektronix 545 Oscilloscope fault hello Dave, 1.) check -150V first of all you have to check the voltages from the PSU, always ! And always at first the -150 volts bec. this is used for reference to provide all other voltages in that PSU. If there is another then -150V , there is a pot to adjust it, and if this will not help write here again. Adjust the -150V very exactly, <1% Tell us if you have a running scope there, if yes check the ripple on the -150V also, if you have a high voltage test head for the multimeter or VTVM? if you have a valves tester? 2.) check all other voltages from the PSU +100V +225V +350V +500V if possible give us a screen picture and of coarse the results of your test. greetings from germany Martin ! take care, the PSU is very powerful, life dangerous voltages !