[Roadsters] OT - Oscilloscope advice?

[James Fogg]

> Sorry for the off topic post, but I thought someone here might be able
to
> help
> steer me in the right direction on buying a new or used Oscilloscope.
>
> Will be used mostly on automotive electronics.
> Most likely looking for a 2 channel scope.
>
> Any brands/models to avoid?
> Any reccomendations?
> Advice?


Automotive scopes are specific to the task and designed to troubleshoot
the high tension side of an ignition system (plugs, caps, rotors, points
and condenser). They don't really offer anything for electronics work.
Most of them use calibrated induction probes, which are unheard of in
the electronics world. Sears made a few homeowner grade auto scopes that
should be affordable.

An electronics scope isn't really designed for the voltages you'll
encounter in an ignition system without a high voltage probe, which
aren't very common. Scope probes are very expensive (considering how
simple they seem), so an HV probe might set you back some big money. 1X
and 10X probes are common and affordable in the used market.

You could make an inductive probe and use an electronics oscilloscope to
work on cars. It's just a coil of wire that is held close to the
ignition wire. You won't know the actual voltage on the plug, but you'll
be able to see patterns and its voltage relative to the other plugs.

By far the most favored oscilloscope brand in the electronics world is
Tektronix. Another good brand is HP/Agilent. You can pick up a nice used
Tektronix 22XX series for probably $200 on eBay. The only scopes I'd
avoid are the ones geared toward television service made by the big TV
equipment makers like Seneca, Hickok, and B&K. There are also a lot of
new manufacturers out there with Asian sounding names you've never heard
of that you might want to avoid (except Hitachi and Iwatsu, which have
been around a long time and are actually good scopes). An oscilloscope
is a precision circuit and I like to work with known manufacturers.