Hi - Did you ever resolve the unstable intensity problem? I have the same problem in my 465B. The intensity will toggle from normal to super-bright randomly.
toggle quoted message
Show quoted text
--- In TekScopes@..., "warren" <wna@...> wrote:
Thanks, Tom. Do you have any idea why the intensity is unstable? I notice that when the unit is first turned on and the trace is dim, it flickers a fair bit. The flickering eventually goes away and usually, after a sufficiently long time, the intensity gets very high, no matter the setting of the knob. I wouldn't expect this to be fixable by re-calibrating the scope.
Thanks again.
Warren
--- In TekScopes@..., "Tom Miller" <tmiller@> wrote:
Hi Warren,
I would suggest that you print out the calibration section of the manual and go
through the adjustments procedure step by step. it starts out with setting and
checking the power supply voltages. There is a part that deals with setting the
grid bias correctly.
Then do pay attention to the vertical adjustments. You will need a pulse generator
and a signal generator to do it right.
Good luck,
Tom
----- Original Message -----
From: warren
To: TekScopes@...
Sent: Friday, June 25, 2010 9:51 PM
Subject: [TekScopes] Some problems with recently acquired 465
Hello,
I am new to this group but not to Tek scopes - I have used a large variety of them since I was a graduate student in the late 60s. I recently retired and purchased a used 465 to help with some projects I am working on. It was from a local person who works for the large local software company and was sold at a good price. At his house, I noticed that the display was very bright and couldn't be turned down very much (it had been on for some time before I arrived). We opened the cabinet and turned down the bias pot in the CRT power supply section and this seemed to solve the problem.
Unfortunately, the problem re-occurs from time to time, usually when the scope has been on for a while. The trace focus is pretty good for a 465 with little blooming at high intensity (similar to the 475 I had in my lab and, of course, not as good as our old 453).
A second problem is the presence of a lot of overshoot on the leading edge of the calibration square wave (with or without a probe, which has been adjusted). This only happens at certain sensitivity settings and seems to occur in both channels (but at different settings).
Any help would be much appreciated. I have the pdf of the manuals, which are a bit difficult to use in that form (I have printed some of it out).
Thanks!
Warren Nagourney
