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Need some R5030 help and a manual.... + temp problem SOLVED!


 

Thanks for the idea of removing the *front bezel* to get at the fiber-optic display on the R5030.
Viewed from above, it seems to be bolted in from all sides in a totally inaccessible way, but maybe
the front path through the bezel does the trick! I will give it a try.

My observation about the covers proved true, *the top and bottom covers were reversed!*
While the covers *DO* have a *FRONT* arrow on them, nobody thought to put BOTTOM or TOP on the covers, and sure enough, the super-hot deflection area was covered completely, both top and bottom.  when I rearranged the covers, there is now a huge flow-through vented area over the deflection board. Clearly it's needed.

Now, when vented, the temps of the amplifier resistor leads rise to almost +70C, VERY hot, but probably survivable. The bad design issue is that in the R5030 rack mounted case, this vented area can be totally covered both top and bottom with other gear, making it too hot again. Drat.  I may still look at a fan here.  This board is very similar physically and electrically to the same deflection circuits in the 5K family scopes, and I was always leery of them due to the terrible heat issues they had, certainly the least impressive parts of those scopes..

I also came up with a slightly demented way to deal with the jammed lighted pushbuttons. Since my situation looked a bit hopeless, I figured it was time for some radical repair action (voodoo technology). I used some MG Chemicals Nu-Trol, and shot it right into the button clearance gap from the front, and cycled the buttons repeatedly. it worked the buttons loose on at least half the switches, and I am slowly bringing them all back to life. Nu-Trol is a good contact cleaner, but more importantly, it is also lubricating, and it seems to loosen up whatever has been mechanically binding in the switch assemblies.  I have to see how this holds up over time, it could just be transient joy at this point.

Now, I just have to get at those pesky bad backlight lamps. That does not look so easy.  I did notice that the vertical noise is huge with the covers off at high deflection values (<500uV/div), I am hoping this will improve once the case is re-assembled. The DC offset between steps is also pretty fierce as I move to the most sensitive ranges, beyond what the front panel adjustment can fix.

all the best,
walter

--
Walter Shawlee 2
Sphere Research Corp. 3394 Sunnyside Rd.
West Kelowna, BC, V1Z 2V4 CANADA
Phone: +1 (250-769-1834 -:- http://www.sphere.bc.ca
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