I've worked with Sun, Allen, and the Snappy Counselor series oscilloscopes, but never a Bear. I've heard really good things about Bear, but never played with one.
Of course, they're "huge space-wasting monsters, obsolete and useless" at this point in time. Machines that cost well beyond $10,000 in their prime sell on eBay for several hundred bucks.
There's no access point to see the primary ignition pattern in the typical electronic-box coil driver used on distributorless ignitions. With no access to the primary circuit, cylinder shorting for cylinder balance testing is also impossible. Secondary pattern is still readable, though.
There is NOTHING like looking at the current draw of an electric motor--such as the COOLING FAN that started this thread--on a digital storage oscilloscope. You can look at the oscilloscope pattern, see the current draw of each individual armature bar, and determine peak and average amperage load, and the motor RPM.
https://www.thirdgen.org/forums/tbi/612473-tbi-fuel-pump-upgrade.html
See post #2 for 'scope pattern on an electric fuel pump.
The problem is that you have to test a shitload of "good" motors--starter motors, HVAC blowers, electric fuel pumps, fan motors, power-antenna motors, etc. to get feel for what represents good amperage draw and rpm for each of them, because none of that is in the service manual. I refuse to replace an in-tank electric fuel pump without looking at the amperage pattern on a 'scope. There's just too much labor in dropping the tank to not double-check the electrical side of the electric fuel pump. About the same for some HVAC blowers, you 'bout have to take the fender off to get at them.
But almost no-one else in the hobby world has an automotive oscilloscope, so there's little point in asking them to look at the amperage pattern on equipment they don't have access to.
At least with scan tools, there's cheap ones brand-new with warranty, and there's pretty-much no other way to do the job. If you want to dick with OBD engine performance as a D-I-Y project, you'd BETTER have access to a scan tool. The oscilloscope can be sort-of replaced with a cheap multimeter and a spark-tester and some common sense.
Of course, they're "huge space-wasting monsters, obsolete and useless" at this point in time. Machines that cost well beyond $10,000 in their prime sell on eBay for several hundred bucks.
There's no access point to see the primary ignition pattern in the typical electronic-box coil driver used on distributorless ignitions. With no access to the primary circuit, cylinder shorting for cylinder balance testing is also impossible. Secondary pattern is still readable, though.
There is NOTHING like looking at the current draw of an electric motor--such as the COOLING FAN that started this thread--on a digital storage oscilloscope. You can look at the oscilloscope pattern, see the current draw of each individual armature bar, and determine peak and average amperage load, and the motor RPM.
https://www.thirdgen.org/forums/tbi/612473-tbi-fuel-pump-upgrade.html
See post #2 for 'scope pattern on an electric fuel pump.
The problem is that you have to test a shitload of "good" motors--starter motors, HVAC blowers, electric fuel pumps, fan motors, power-antenna motors, etc. to get feel for what represents good amperage draw and rpm for each of them, because none of that is in the service manual. I refuse to replace an in-tank electric fuel pump without looking at the amperage pattern on a 'scope. There's just too much labor in dropping the tank to not double-check the electrical side of the electric fuel pump. About the same for some HVAC blowers, you 'bout have to take the fender off to get at them.
But almost no-one else in the hobby world has an automotive oscilloscope, so there's little point in asking them to look at the amperage pattern on equipment they don't have access to.
At least with scan tools, there's cheap ones brand-new with warranty, and there's pretty-much no other way to do the job. If you want to dick with OBD engine performance as a D-I-Y project, you'd BETTER have access to a scan tool. The oscilloscope can be sort-of replaced with a cheap multimeter and a spark-tester and some common sense.
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