--- In TekScopes@..., "empr1o" wrote:
Thanks Steve,
You are right that I'm not familiar with all the terms. Some hope introduced here.
Turns out that the one that is smashed has a smashed getter! The remainder of what I write is about the other---the one that has a hairline crack in the getter.
Turns out, I guess, that I don't know if it is the crt that's cracked after all. From my reading all I can see outside of the big case is the getter.
I have seen something of a sign of life along the way. A dot marking in a small circle in the top left corner. It didn't respond to anything, and didn't seem all that healthy.
Tonight, (Eastern) I'll take another look at this getter business. Like I said, I've got all these parts and I'm not sure if any or all are in order.
One other thing---I don't have any probes yet, as I'm not sure I have a scope to connect them too! Will I be able to determine viability without a probe?
A probe is convenient for testing a scope, but not essential. A paper clip can serve the purpose as well.
If you have a probe or a BNC cable that brings out the center conductor to a bare wire, you can use it to connect from the vertical input connector to the scope's calibrator signal. This will allow you to see a square wave if the V/div and Time/Div controls are set properly.
To use a paper clip, bend the end of the wire to allow it to stick out so you can touch the center of the vertical input BNC connector. With the V/div set to a low setting like 10 mV/div or so, and the time base set to 5 ms/div or so, you should see deflection in the trace synced to power line frequency. Basically your body is acting as an antenna. If you switch to LINE trigger on the time base, note that the waveform remains stable.
Note that this technique only works with high impedance (1 M ohm) inputs. Plug-ins with 50 ohm input impedance such as the 7A24, 7A19 or 7A29 will not likely see any signal as the input load is too great acting on the antenna coupling your body is providing ¨C basically the scope is shorting your body to ground ¨C the same as touching the ground connection of the BNC connector.
- Steve
