[Coco] Re: Buying scopes -- -- -- was CoCo RGB video timing and levels

[Rogelio Perea]

James Dessart wrote: 

> Since people here seem to know about oscilloscopes, I'll ask a 
> question. :) When buying off eBay, a lot of the lower priced units come 
> without probes, power cords or manuals. Let's say I get one, and the 
> probe, what kind of power cord do they typically use? And are they easy 
> to operate? I've never touched an oscilloscope in my life, but I 
> understand the principle.

Usually the equipment uses the standard 3 prong AC plug exactly as the one used for PC power supplies. That one you can get from almost every hardware store.

As far as ease of use, it ll depends on what kind of signals you are working with, and what information you expect to retrieve from the trace on the scope screen. There are some high end units that are computer based and will just about mince every detail about a given signal in nice digital text readouts, and they're fully programmable also... these type of osciloscopes usually can store a digital rendition of the signal for later review or archival uses. Its complexity in use accompanies the usefulnes of their "output". Whit a more basic scope you usually have fewer knobs to turn:

a). One that sets the range of the voltage level to measure, much like a voltmeter
b). Another that sets the frequency at which the scope "tracks" the signal beign analazyed... the horizontal 'time' range
c). The knobs that adjust the signal to be IN properly presented in the screen, vertical & horizontal position, etc
d). and perhaps the knob that controls the intensity of the trace on the screen... the brightness, plus the one that focuses it.

There are more, teh above list is merely a broad overview of scope controls.

For the CoCo, I know at least of very basic scope program that uses the joystick port as signal input, Bill Barden wrote it as for an article in The Rainbow - more of a demo than an actual diagnostic tool for electronics though. With added external electronics plus an ML driver probably it could work out as a decent basic digital scope.



-=[ Rogelio ]=-