So, here the promised. First the pics of my new scope as delevered by the ebay seller:
Here remnants of the double sided tape once securing the pouch ( with probes, cables etc ) to the top of the smaller enclosure are clearly visible.
In the upper left hand corner you can see the last calibration sticker (green circle with dates etc, this one was officially calibrated up to 6/12).
These two pics show the detail of the remnants of the round sticker all scopes in the industry have to carry to atest they are calibrated at prescribed time intervals - usually yearly.
Electronics in industry and lab use is not pampered the way we use home audio gear - there will be scratches, dents, stickers, tape and other remnants of unmentionables telling it HAS BEEN USED. Contrary to home, particularly vintage equipment, such electronics has to conform to certain standards and is tested/adjusted=calibrated accordingly - usually on yeary basis. Pics also clearly show knobs dirty from regular use, everything within the normal .
The remnants of stickers/tape are particularly stubborn and rather hard to remove without damage to the surface below. The most usual catastrophic failure is to use alcohol (based) cleaner - it is HIGHLY LIKELY that you will get it clean - TOO MUCH, by partially or completely remowing lettering. There is lots
collectible (prior to alcohol treatment at least... ) vintage McIntosh etc gear - reduced in resale value by painful % by this common error...
The "cleaner" I have yet to fail me or damage anything is good ol' - WD40 (or its
reverse engineered equivalents ). This thing will dillute the most stubborn remnants without damage to the surface below. Application is as follows:
1. You need an (old) medium hardness toothbrush.
2. WD40 or equivalent
3. NEVER apply the WD40 by spraying to the surface treated directly; at least not until you acquire enough experience when it is safe to do so. ALWAYS spray the WD40 from the closest proximity possible to the toothbrush first
4. GENTLY start scrubbing the surface with remnants of tape etc - the surface has to be damp, but not wet; excess WD40 can leak inside and cause ???, so use it sparingly. Brush the surface say every 10 minutes, so that it does not dry; WD40 evaporates, you may need to apply some more to keep the surface damp. I suggest working in a well ventilated space; WD40 has quite a powerful odour/smell and is not the most healthy substance to inhale. You will see that dirt/grime is loosenig up and say after half an hour the treated surface will be visibly better looking. You may want to repeat until satisfied with the result.
It is OK to "drown" most affected portions with WD40 and leave it working. Specially on "pebbled" surface, as customary on Tektronix scopes.
Only damp brush on the front plate, particularly around switches, levers, etc, where liquid could do damage to internals :