(01-10-2015, 12:20 PM)barnbiketom Wrote: I always wanted a scope, but never got around to it. Now I see apps for scopes and wonder if anyone has had experience..
Some use the mic audio input, any thoughts????
some require a usb based probe?? ut I am clueless ( no they have Digital scopes in a black box with just one USB port for digital comms) Most can not handle spikes.
USB is just a power source, and a very high speed balanced SERIAL transmission line (data), that is all it is. Wiki it.?
I also already use the android app TORQUE free version and it works GREAT with a $15 cheep bluetooth data port connector!!
I sometimes wish I could monitor wires just to see what is what..
Yes, that is the best first start.
to see and learn voltage over time presentations.
the band width will be limited, and many not allow watching say injectors.
the sound car is mic is a cheap analog do digital converter, same magic of the modern scope (DSO) but vastly slower, and free.
the reals scope has one more feature, that allows the user to not blow up the scope, 400v to 600v input protections, no mic amp has, nor needs.
Cars electrical system are vary noisy, and can produce noise spicks easy from relay noise, , alternator, and the worst is the A/C clutch solenoid,
cheap scopes work great for testing DIY made, circuits. like Aurdino card, projects, or ? all low voltage.
for sure a scope wins best, at injector or any PWM (ISC?) Signals. and for looking for excess noise. or live oxygen sensor actions.
many sellers, avoid the max input spec, to make a sale, (lies through omission, or as they say in Sales, Spec'-men-ship" (sic)
you need a quality scope card, to do this right,and best is with 10:1 probes,
here is one that can take 80v p-p (means peak to peak) or 400 with probes.
about the minimum off shelf scope.
http://www.ebay.com/itm/ARM-DSO203-Nano-...259359cbd0
you need 10mhz scope, bandwidth minimum. the above does not spec out vertical band width at all. just a guess on my part this will work. (so many sold...)
what i need is to resolve , 200 uS , on the injector (modulation pedestal)with no reduction in vertical accuracy, (reals scopes spec this is % at a many frequencies)
im guessing is this would work. 72/ms/s
so much can be learned watching COP coils and injector pulsed, on a running engine.
for bench only work, no killer SPIKES (cars)
see this, learn to build yours scope
and make it work
http://www.ebay.com/itm/Mini-3MHz-Analog...2ed06367ad
