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gregz gregz is offline
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Default Tektronix 565 repair

Phil Allison wrote:
GS wrote:

--------

Been playing with this scope for some time. Original problem, blowing 10
ohm 2 watt surge resistors in supply. Replaced a couple caps so far, not
sure if they had problems. I can bring up on variac and run, no problems.
200 ma. Draw on each of 3 resistors. I still burn resistors on full power
up. Not sure if replacement resistors are suitable. Thinking now of upping
power from 2 watt types.



** Surge tolerant resistors rely on thermal inertia of the resistance
material - so there is not much change in conductor temp during a short current surge.

Wire wound types are the obvious choice, though solid composition may do
as well if you can find any.

If you have been blowing thick film resistors then try the same rating in WW.



.... Phil


Thanks. These things make a pop and a little hole.

Greg