Wibbly Wobbly Oscilloscopey

April 4, 2013 12:13 PM

Can I hook up an iPhone to an old oscilloscope?

So I have these two old oscilloscopes that I got when a school district auctioned off some property. I think it would look neat if I could get one to do its thing when my iPhone plays music. So what cables would I need to buy/make? Is it even possible?

I'm thinking I would mount an iPhone/iPad charger on top and just charge the iPhone normally. Then would it be possible to deliver sound from the iPhone to the oscilloscope input as well as a pair of speakers so I could hear the music? Would it be as simple as getting a headphone cable splitter? What kind of cable would I need to be able to hook up to the connections on the front of the oscilloscope?

Please provide links if possible. I'm resourceful and crafty, but not very physics saavy. So saying "buy cable X, plug it into Y" is along the lines of what I'm looking for. I do have a wire stripper at home, so I can modify a cable if needed.

posted by MsMolly to Technology (9 answers total)

Well, I've done this in a non-permanent fashion with clip probes and an 1/8" male to 1/8" male audio cable, by just clipping the probes onto the exposed male plug (after plugging the other end into the iPhone).

To make it permanent, you'd just combine the two, although I am not sure a wire stripper would be enough for the task.
posted by destructive cactus at 12:28 PM on April 4, 2013

Best answer: The easiest way to do this, from stock parts I can find:

- Headphone splitter
- Headphone to RCA
- 2x RCA to BNC
- 2x BNC to Banana

Plug the things together in that order (the headphone to RCA gives you two separate sets of things, one for each stereo channel) and plug the terminal banana plugs into the same color holes on the oscilloscope.
posted by Maecenas at 12:28 PM on April 4, 2013 [2 favorites]

Oh, yeah, I neglected to look at the type of oscilloscopes first. Banana plugs!
posted by destructive cactus at 12:31 PM on April 4, 2013

Best answer: This cable plus a 1/8" male-male cable (of the type used to plug your iPhone into a car stereo, like the one linked above) should do it, even though it is apparently for tattooing equipment.
posted by exogenous at 12:40 PM on April 4, 2013

Best answer: What are the labels above the pairs of Red and Black banana sockets on each scope? I'm guess it's something like Input 1 and Input 2, in which case Maecenas's way should work and give you two lines on the scope. Extra groovy.

Using a headphone splitter is a good idea because it is super cheap, but it may make your audio from the speakers sound less than great. It might also make the amplitude of the signals on the scope too low for a good mad scientist vibe. If so, you can use the headphone port for the scope and get your audio out of the 30-pin dock connector with something like this: Dock to Audio and USB

If it were me, I wouldn't put my iDevice right on top of one of those things. An old CRT scope might have some serious magnetic flux which could screw with your hard drive. A few feet away should be fine.
posted by BeeDo at 12:49 PM on April 4, 2013

Ignore me, do exogenous's thing—I tried to find that same cable but couldn't, and his way will be cheaper and simpler.
posted by Maecenas at 12:58 PM on April 4, 2013

Response by poster: I can't believe it took me so long to ask Mefi how to do this! Thanks guys, these solutions look perfect!
posted by MsMolly at 2:08 PM on April 4, 2013

You could also feed the left channel into one scope input and the right channel into the other scope input and then put the scope in X-Y Mode.
posted by Confess, Fletch at 2:24 PM on April 4, 2013 [1 favorite]

If so, you can use the headphone port for the scope and get your audio out of the 30-pin dock connector with something like this: Dock to Audio and USB

As far as I know, there is no way to make the iPhone send audio to both the dock interface and the headphone jack.
posted by aubilenon at 3:26 PM on April 4, 2013