Logic probe vs logic analyser

[3pcedev]

If I had the cash I would get one of these. Almost as small as a DMM, has all the functions and simplicity of a DMM if you desire but it's a full on oscilloscope.

Years ago my employer supplied me with one. It was unbelievably good, pity I couldn't take it with me when I left.

 

[Dwight Elvey]

There is one little tool that I lusted after back in the day--the HP E2310A Logic Dart. Less than a logic analyzer, but more than a logic probe--it seemed to be the ultimate handheld probe for digital circuitry. It was also very expensive.

HP also made a tool that one could see, as little as 100ua flowing through
a pin. It was great when one would trace it down to one net, stuck high
a 5 IC's on that trace.
One would just probe all of the dip leads and see which way the abnormal
current was flowing. It wasn't a hall effect, it had 3 contacts as I recall.
Dwight

 

[mwillegal]

After a multi-meter, the next tool I would purchase is an oscilloscope. In fact, though I used logic analyzers extensively in a professional capacity, I've only run across a few occasions where having one for my hobby activities would have saved me substantial time, and in every case, I was able to solve the issue, with other tools that I had on hand.

Note that for slow signals, up to 30 KHz or so, with some sound capture software and the right interfacing, you can use a stereo sound port on a PC, as a simple two channel digital storage scope.

regards,
Mike Willegal

 

[KC9UDX]

I've got a bunch of nice scopes, and a logic probe (and a plethora of VTVMs and the like). I've always wanted a logic analyser (and a spectrum analyser).

Almost every time I set up a scope to work on a computer, I end up doing the job with the logic probe.

Knowing the limitations of your probe, and how to interpret what it's telling you, are very, very important.

You can deduce things that the probe isn't supposed to be able to tell you, by comparing signals.

Also, it's important to understand a circuit and when you can or cannot force a level. I would have found the bad OR gate above that way. It doesn't make sense to me to assume an OR gate being pulsed is working correctly without being able to force the inputs low (or having an analyser).

 

[glitch]

If you can find a Tektronix 6401 logic probe, I highly recommend it. One of the problems mentioned in this thread, not knowing the state of a pin w.r.t. the state of another pin, can be solved with the 6401. It has a strobe input that will display the status of the probe tip when the strobe input is either high or low (it's selectable). With my old logic probe I used to have to breadboard a little latch circuit when I wanted to do that.

Still, even with that functionality built in, I don't use it very often.

 

[Dwight Elvey]

If you can find a Tektronix 6401 logic probe, I highly recommend it. One of the problems mentioned in this thread, not knowing the state of a pin w.r.t. the state of another pin, can be solved with the 6401. It has a strobe input that will display the status of the probe tip when the strobe input is either high or low (it's selectable). With my old logic probe I used to have to breadboard a little latch circuit when I wanted to do that.

Still, even with that functionality built in, I don't use it very often.

An almost dual channel scope with trigger.
Dwight