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Looking for something portable and not satisfied with jailbreaking, or paying a metered fee, maker Adam Byers decided to build this interface box to record calls made on his iPhone.

[via @adambyers]

Adam Flaherty

I make cool stuff and write about other people making cool stuff on If you have something you think I should see, send me a tip.



  1. alandove says:

    I’ve seen (and tried) numerous call-recording hacks in my work as a journalist, but that was before I found the head-slappingly ingenious Olympus TP-7 miniature microphone. It’s a simple electret mic that plugs into … your ear. Interposing itself between your eardrum and the phone speaker, it easily picks up both sides of the conversation, catching everything you hear because, well, it’s in your ear. Plug its cord into your recording device of choice, and you can tape any call on any phone, anytime. sells it for about $18.

    I think the only reason people continue to come up with clunky hacks to record calls is that they haven’t found the TP-7, or they have, but they can’t understand how it works because it’s so ridiculously simple.

    1. Adam says:

      Oh, cool that’s my blog! It’s on honor to be on Make!

      It’s funny – in all my searching up till I decided to make the breakout box I did not come across the TP-7. So for a device that is made to record phone calls, even from cell phones, it’s not easy to find. I certainly didn’t see it come up in my searching. So, shame on Olympus for not marketing their product better.

      On the other hand I’m curios to know how it gets both sides of the conversation. It goes in your ear so it gets the side of the person your talking to through your phones ear piece but how is it getting your side? Phones feed a smidgen of your voice in your ear piece but, as I mentioned in my post, it’s far to little to get a decent level from on a recording. So it must just be getting your voice by picking it up directly from your mouth. Interesting device but I wonder how well it gets “your” side of the conversation being as it’s in your ear covered by a phone but at $18 I suppose it would not hurt to try it.

      Do you have an audio sample that you could post somewhere? I’d love to hear it.

      I’d disagree that what I made was “Unnecessarily Clunky” for what I was setting out to accomplish (given the information I had) I think it’s the least clunky, most basic way to do it. I could probably fit it all into a smaller box to make it less bulky but I used a box I already had. And I bet that mine works better in respect to getting both sides clearly since it’s recording directly from the mic input of the iPhone and not relying on picking up my ambient voice, like I believe the TP-7 is doing. Be interesting to pick one up and play with it to see how well it works.

    2. Adam says:

      My solution also affords you the ability to use an external mic and headset with your iPhone (even if you don’t record, connect you iPhone to a PA system, plus other perhaps more seedy things like insert a voice changer between you and the caller. I think this setup woudl also work better in a podcasting type situation.

  2. Steve says:

    I’m interested in purchasing one or maybe you would consider just selling the plans?

    1. Adam says:

      I can make ya one if you want – e-mail me:

      adam [at]

      The schematic is posted on my website (linked to in the article above) and everything on my site (that’s my original work) is under a Creative Commons Attribution-Share Alike license so your free to take the schematic and make your own, improve upon my design, sell it yourself, make millions whatever. So long as you abide by the Creative Commons license.

  3. Rex2010 says:

    Thanks for the great article.
    I use WM Sound Recorder to record my HTC Touch Pro phone conversation. It could also record outgoing and incoming calls automatically.