Wednesday | December 19, 2007

iPod Touch Mic DMD : Do-It-Yourself : Part 2


This is the 2nd part of the Do-It-Yourself tutorial on building the external Mic for the iPod Touch.

Last time we finished the circuitry, and now as you check the Mic and see the one millimeter distance between its legs, you are saying: "noooo- waaaaay, I am rather adding a 3.5mm plug for (external mics and a headset)?"

Yess, ok, just check the photo below. What do you think the weight ratio between the Mic preamp and that big external cable is?


Roughly 1:10? And how heavy it is going to be when you plug in your headset plug? Not to mention when you start to pull that 0.5kg cable? You do not wanna destroy the Dock Plug of your brand new Touch, do you?! So, now that you know there is (almost) no other way but to add that beautiful tiny mic you anyway ordered, let's do it then!

12. Let's start by approving the fitting of the construction you made up to now. Try fitting it into the metal housing of the dock connector. (the image was made before the capacitor was added as we check it several times during the construction).




13. Fits? Well done. We are going first to connect the 3rd leg of the IC to that 15k resistor on the bottom. Then the next step is to connect the 6k8 resistor to the end of the capacitor (yellow on the image). And finally to connect the GND of the IC (leg 4) to the GND of the Dock (PIN 30 or 29).





14. Trick nr1 today: we are reusing one pin of the Dock Connector you removed as the future Gnd line of the Mic. Pls note the pin is shaped into an L-shape that exactly reaches the GND of the mic, but also does reach out behind the edge of the mic cylinder around 0.5 mm. This will not let the Mic fall out, even in hot situations. Add also a 10 mm wire to the "line-out" pin of the mic.



15. So Let's add the Mic! Connect the black wire of the mic to the Cap where it meets the 6k8 (4k7 or a little lower value) resistor.


16. Since the whole construction is going to be placed into a metal housing that is directly connected to the ground (remember), we need to protect the parts we connected up to now by plastic self-adhesive folia strips (from your paper-shops).


17. Ready? Close the whole metal housing, by keeping the mic wire between the bottom metal part (the bigger one) and the folia strips covering pin 4 of the IC. The mic should reach out just so-so!!!



18. Add the bottom plastic cover (there is a label inside saying "Bottom"), and the two plastic buttons as depicted on the image. Left and Right are the same.

19. Push the Mic GENTLY into his final position by keeping it away from the folia-covered IC legs. Now fix the mic GND leg with another folia strip. Good! We are close :)



20. Close the plastic box first without a glue, then glue the four corners and the edges next to the mic, and push it together. Here we go. After the glue part is done, check if the plastic buttons still work. If not, push them gently until the glue release them.

21. Plug in your mic, load VNotes that was sitting on your Touch since the first day you got it, and enjoy its Voice functions!!!



Ok, now, please, Donate a little, if you liked this tutorial, or you are thinking about supporting our Project. You may click on the "Donate" link at touchmods.net. Thnx.

Cheers, Marian
Posted by mrn at 01:41:44 | Permanent Link | Comments (34) |
Comments
1 2 3 4
1 - Awesome job marian. (Comment this)

Written by: RadicalxEdward at 2007/12/19 - 05:52:10
2 - i know it said that the 6.8k resistors were not foundon newarks website and you substituted with a 4.7... can we still use the 6.8?

||_GuY_|| (Comment this)

Written by: ||_GuY_|| at 2007/12/19 - 06:29:56
3 - How Much is the complete mic?? (Comment this)

Written by: Anonymous at 2007/12/19 - 06:58:54
4 - there is no price yet as we are just finishing up the production of the first batch (Comment this)

Written by: ||_GuY_|| at 2007/12/19 - 07:54:49
5 - ps... help mrn finish this project and donate, see you all in the new years (Comment this)

Written by: ||_GuY_|| at 2007/12/19 - 07:55:25
6 - 6k8 is ok, 4k7 is ok, 3k3 is also ok! The reason for the 6k8 was that in case of using the Conrad Mic it exactly shared the Ucc with the Mic in a 50-50% way. Your mic can differ and it is more secure to use lower values, then higher.

Price: I think we should agree that all providers will offer the complete mic around 30 Eu + Shipment. We already have like 4 extra providers :) I will collect and post the addresses in like 4-5 days?

Thnx guys! You are making a better world! (Comment this)

Written by: mrn at 2007/12/19 - 11:40:48
7 - "Connect the black wire of the mic to the Cap where it meets the 6k8"

Right at the with the wire of the 6k8 where it meets the Cap ?

Something like this ?

[6k8]--------[CAP]
(mic)-------/ (Comment this)

Written by: Anonymous at 2007/12/19 - 11:51:40
8 - yes. just check the schematic,
http://touchmods.blog.com/2420619/
and one important point: the mic has two pins:
(+) .. the one that is NOT connected to its housing - goes to the R and C.
(-) .. the one that IS connected to the Mic housing - goes to the GND (through that Pin you stick to the Mic House. The mic housing provides Gnd, without any ground loop. No worries. (Comment this)

Written by: mrn at 2007/12/19 - 13:29:45
9 - Thanx Marian, ur awesome ! :D


pHiL (Comment this)

Written by: Anonymous at 2007/12/19 - 17:10:50
10 - Hey Marian

Little question, why is there adhesive on the last picture ? I mean, you have to put adhesive inside, but why outside ?

Thanks for this great tutorial =)) (Comment this)

Written by: DarkM at 2007/12/19 - 19:58:55
Write a comment






1 2 3 4