The Apple diyMod: My Take on the Famous iMod [56k killer] Featuring 3G, 4G, 5G and nano 1G! - Page 52

Good to see more people enjoying this mod.

I, too, had the problem of the pad being lifted due to bad wiring. It is a pain, but soldering to the chip isn't all that bad. How did that 26AWG work out for you? And how is your faceplate relative pre-diyMod? Using 32AWG, the faceplate lifted quite a bit and produced a little dip in the click wheel region.

You're right about the internal headphone amp, though. Keeping the caps in place right after the DAC would allow it to keep running, but might I ask why you'd want to do that? You'd have overall greater power consumption, signal degradation, etc. As far as I know, that's where all the circuitry is lying though it hasn't been fleshed out by anyone, which I'm guessing would be near impossible due to the multilayer PCB. Then there's the issue cfcubed brought up about the DZP-labeled transistors. For all we know, those are the opamps that RWA mentioned on the iMod page that is contributing to the signal loss, so maybe those guys have got to go as well. From what can be seen in the 5G photos on the OP, the sound goes into them, but where they go, no one knows.


iQEM:

Keep chugging along, brother. We've all been waiting a long time for you to finish that diyMod nano! Give it a couple hours work and you'll finally get to join the club.

I think you've made your point.

Sounds good, Christine. Do you still have those extra BGs you had from before? If not, I can send you a pair or so.

Actually, I just picked up a friend's broken iPod 3G last night for $50. The 15GB hard drive on it was fried, but somehow I was able to squeeze in my old 4G's 20GB hard drive. It's so awesome. I love the front panel on the 3G and the red buttons when I turn on the backlight. The only downside is that it doesn't charge via USB or my laptop's 4-pin FireWire port, but there isn't any power on that connector anyway. It'll probably be my home rig diyMod. I just ordered an 1100mAh battery for it, and I just got a new shipment of BGs in yesterday. Let the modding begin!

Just finished my diyMod 3G. Throwing those BGs was kinda tricky at first, but it went down okay. I fit the caps on either side of the hold switch lever, taped them down, it's all good. Burning in now.

I agree about the 5G's vulnerability due to external capping. d_w31, the one whose iPod 5G I diyModded, wanted me to check his iPod speaker dock so he could use it safely. One of the great things about the diyMod is that you can personalize it to your own uses. For instance, the loading and series resistors don't have to be implemented by everyone, and caps can fit to your sound tastes. If the diyMod will always be used with a high input impedance amplifier, the resistors to ground aren't required. They are meant to reduce the effects of hooking up a low impedance load to the DAC, so if you're always using a low impedance load or always using a high impedance load, they can be omitted. For series resistors, they are meant to protect the DAC from misuse, which we have inconclusively concluded to be from paralleling voltage sources with the DAC. If you're going to be docking your diyMod, you can use bigger caps than the BGs for different sound flavouring. And not only different cap brands but also different cap configs, much like vvs_75's Auricap and CAvanessia's Sonicap dock. cfcubed has chosen his path of diyModding, and that's great because it serves his needs. Glad to hear you're enjoying it, buddy.

An idea I was floating in my head was doing a dual diyMod, where you send a BG'd signal to the headphone jack and sever the existing signal. This Wolfson paper suggests using 220uF caps with a 32ohm load, but fitting that size caps in any of the iPods isn't practical. What I've thought of is taking the headphone signal (not the line out signal, the one controlled by the click wheel) and putting a 1kohm resistor after the cap. Stackpoles come in sufficiently small packages, so it won't be too hard fitting it in, say, the diyMod 4G or iPod 4G. I addressed this matter because I gave my dad my Mini^3 since it was smaller than the PIMETA I made him, so now I'm listening to my iPod unamped. As such, the bass rolloff is pretty distracting when I'm used to listening to the Mini^3's flat FR. I'm not sure what exactly is going on in between the DAC and HP jack, but if I can just yank the signal and personalize it for flatter bass response, I could enjoy my diyMod even further. Some of you may want to also consider it.

Yeah, sorry about that lack of clarity. That one photo was actually done by the iPodlinux guys, and vvs_75 showed the ones from which we obtain the signal. KerryKing has a website featuring some of his DIY work, so check it out at Erik's and Sven's DIY page under "Erik's Gallery." It seems to be identical to the 4G click wheel, but I'll post it in the OP for future reference. Thanks for pointing that out.

It wasn't that hard. Just use the Search function and put in "KoKoKrunch" for the username and "iMod" in the search terms.

How much offset are you getting, Kerry? There are only 4 solder points you really need to make (take signal, to cap, out of cap, dock connector), so if it's in the tenth-of-a-millivolt range, it could just be the DMM. Your pictures seem to show pretty solid connections, so it could just be that. Try it with different caps to see if the problem is the onboard solder joints. Sometimes those pads can be difficult to work with, so see if you can find any equivalent pads to which you can solder your wires.