Tektronix 465B Scope - Some problems.
I have recently acquired a Tektronix 465B scope. Although it is in working order on running it and making some checks I have found some problems.
I will run through them, also there are pictures for all but one item.
1/. Not a fault really but something that threw me until I read the service manual. Although the vertical Volts/Div switches are marked up to 50V per Div the 3 top ranges 10, 20 & 50 V/Div are not usable. The switches do not rotate any further than the 5V/Div position. I found that rather strange, why mark them up to 50V/Div? (Image 002)
2/. The two traces are fuzzy with the Astig and Focus controls set to their best positions. Image 001)
3/. With a slow timebase it can be seen that the spot is distorted. The Focus and Astig controls change the shape of the spot more than focus it. (Images 3 & 3a)
4/. With an input signal to the vertical inputs the fuzzy traces can clearly be seen. (Image 4)
5/. The effect of the Focus control shows distortion quite clearly. Rather more than just defocusing. (Images 5 & 5a)
6/. The beam find does not show a clean round spot, it shows a short line with distortion at the centre of the screen. (No Image)
I was wondering if I may have a dirty/faulty power supply?
Would be grateful if anybody could point me in any direction regarding the above faults.
Also of any known faults that I should look at.
I have the service manuals, but it would be good to have the operators manual if anybody knows where this may be found.
Thanks
Dave.
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