Question about Oscilloscopes

Cliffo

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I just got a Hitachi V660 Scope from work. My question is this... Is a 60MHz scope adequate for arcade board work, or is it much like with a logic analyzer where you want a speed of 10x that of which you are testing? In which case I'd want to find a scope of 100MHz or higher.

It was free, so I'm not complaining, but need to buy probes and want to make sure it's going to be usable before I do that.

Thanks!
 
I have used an old BK Precision 20 MHz for old Atari classics like Asteroids and Tempest, and it worked fine.

It depends on what games your going to be working on and what part of the circuit, newer games run at a faster bus speed so you would need a faster scope. Most of the early 80's games stay below 5MHz on clock speed I believe.

Genreal rule of thumb I have always heard is 5X the speed you are trying to check the signal on with an analog scope. The ratio is a bit higher for digital because of the sample and aliasing that can happen.
 
I just got a Hitachi V660 Scope from work. My question is this... Is a 60MHz scope adequate for arcade board work, or is it much like with a logic analyzer where you want a speed of 10x that of which you are testing? In which case I'd want to find a scope of 100MHz or higher.

It was free, so I'm not complaining, but need to buy probes and want to make sure it's going to be usable before I do that.

Thanks!

60 will do fine for your purposes. The 10x recommendation is for sampling-type systems (digital scopes, logic analyzers, etc). When you've got an analog scope, as long as the bandwidth of the scope is > the frequency of the signal, you're good to go. Just make sure you get probes that are the same rating as the scope, and you'll do just fine.
 
I have used an old BK Precision 20 MHz for old Atari classics like Asteroids and Tempest, and it worked fine.

It depends on what games your going to be working on and what part of the circuit, newer games run at a faster bus speed so you would need a faster scope. Most of the early 80's games stay below 5MHz on clock speed I believe.

Genreal rule of thumb I have always heard is 5X the speed you are trying to check the signal on with an analog scope. The ratio is a bit higher for digital because of the sample and aliasing that can happen.

Cool, sounds like I should be fine then. Most of my games are rather old, only a few are relatively recent.

Thanks for the input, now to find probes for this beast.
 
I just got a Hitachi V660 Scope from work. My question is this... Is a 60MHz scope adequate for arcade board work, or is it much like with a logic analyzer where you want a speed of 10x that of which you are testing? In which case I'd want to find a scope of 100MHz or higher.

You should be fine for most things. eg. Pacman 18MHz max, and most of the early Namcos, williams 12MHz max. Getting to some of the later boards around 1987+ master clocks are 49MHz with logic clocked at around 24MHz. Most of the classic boards are running slow enough for a free 60MHz scope to be useful ;)

- James
 
With oscilloscopes usually you'll be looking at edge rates, undershoot, overshoot, rise times, fall times, and comparing them among two or more channels. So with an oscilloscope you'll need a much higher bandwidth i.e. sampling frequency than a logic analyzer to be able to see all of those things. I'd recommend a minumum 10-20x the fastest edge or glitch you expect to see.
 
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