I have neglected my blog for a while, whilst still doing my projects and schoolwork; so I have alot to get caught up with (hopefully I can remember what I did!).
Over 3 years ago I wanted to make an NES controller into a cellular phone. My idea was more ambitious then my skills at the time, to say the least. And also, at that time I only had a Radioshack pencil soldering iron to use (that couldn't wet up, except in one tiny spot. It was horrible). So when I stumbled upon a cheap (~$18) Motorola bluetooth headset, my idea changed. Although there was some SMT soldering involved, it was much less work than wiring up the keypad of a cellphone. I couldn't find many examples on the internets of this being done except for the banana headset, and the payphone headset.
Edit: I just found this blog of an NES BT, but at the time I wasn't aware of it (just found it for completeness sake.)
It took me a while to get an idea of how to charge the internal battery, because the original bluetooth used a single AAA for power. I opted for using a rechargable AA for the extended battery life. My idea of charging the AA was to use a 2 cell AA charger and hack into one of the charging docks and break it out to inside the controller. I found out later that I really didnt need that on/off switch. Removing the battery in the charger has the same affect.
Anyways, I opened it up a little bit ago to take some pictures...
As you can see the wiring is a mess! All the spare wires were ones I had laying around, or could cut off of something else. I wasn't too proud of the work I did on this, but it was working for a long time. This BT has a sad ending though. I applied a little too much voltage to charge the AA (no voltage regulation from the battery charger) and toasted the whole thing. But I still wanted an NES BT headset, enter NES BT Part 2.
My old Sony cellphone came bundled with speakers and a bluetooth headset that could never stay on your ear. Perfect specimen, and the price was right. I made a cleaner cut of the original PCB to fit in the BT as well as better soldering all around thanks to my Hakko 936.
The Sony Ericsson BT is better than the Motorola one I used in the first NES BT because it has the rechargable batteries included and my cellphone charger is able to charge it up. Battery life is around 4 days with moderate usage.
I had to cut off some of the standoffs around where the cord used to go, so I could fit in my 1/8" mono jack used for charging. I enlarged the hole a little with a 7/16" ? drill bit.
Soldering on the Kynar wire wasn't that big of a deal, even with my medium size tip on my iron. The secret is lots of flux! I used the speaker and mic from the BT and just hot-glued it in. At my previous work I used Loctite 3936 UV acrylic and would have loved to use that here, but I wasn't able to get any in time for the project.
I had to trim the PCB a little to fit in all the guts. The best way to do this without cracking the PCB is to first score the PCB with a knife along your desired path, and then use some cutter to trim it up. I did not do this the first time and you can tell! Before you cut the PCB you might as well remove the HD14021 shift register first to use in another project.
I used the up and down buttons on the D pad for volume and the start button for call/end call. Use the knife to scrape off the solder mask to expose the bare copper trace and solder to it. Use lots of flux, or a fiberglass brush to clean it/rough it up first.
Using a small drill bit I made the holes for the mic and speaker. In the first version I just used the xacto knife and twisted it to make to hole. Worked like a charm.
I lost my steam by the end of the project so I didn't do an "appropriate" charging cable. So I just soldered an 1/8" mono plug to the original charging jack and used some good ol' hot glue to keep them from shorting out. Works good enough for my daily use. I would like to make something a little better, it's just that I am too lazy.
Finished product. Works good. Although there is a law in my province that forbids you from using a cellphone while driving, I think it would be interesting to see what a police officer would say about this.