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Pxxx: Prototype / Modified Audio Accessories

7 replies · 5,719 views · Started 29 December 2003

I have been perturbed by the annoyance of not being able to connect my favorite headphones to
my Pxxx mobile phones. The common issue that most mobile phone device users share is the
inability to use their unit (equipped with standard 2.5 mm input jack) with common audio devices
that more likely utilizes 3.5 mm output jacks. There are no BT audio device patchers in the market that
would eliminate the use of cables just yet. The only promises I have seen on the
drawing board thus far is a streaming mp3 BT stereo headset and a BT audio jack adapter. With that said,
I still don't believe we will ever see full compatibility with all of our common audio devices accross the board.
So I took about 1/2 hr of my time to modify some electronic components to enable compatibility with
the P800/P900 without the use of 'extra adapters'. The main focus of this project was to simply
'down convert' all standard 3.5 mm output jacks to 2.5 mm output jacks.
Here are the audio components I worked with below:

Components:

  • External Mini Speakers (Flat Planel)
  • External Mini Speakers (Clamshell)
  • Portable Speaker Amplifier (AC/Battery Operated)
  • Stereo Headphones (Foldable)
  • Stereo Audio Patch Cables

The speakers are very handy when trying to play audio/video from the Pxxx source speakers. Despite the
audio levels of the encoded audio/video source the sound is never loud enough in a noisy environment. With
that said, I added a portable amplifier to boost the output audio signal by at least 5 times that of what the Pxxx
speakers can produce. The results were phenomenal. The Pxxx was still audible from one end of a crowded
train car to another where the Pxxx speakers faded out at less then 1 meter away. There are two types of speakers
pictured below. One is a flat panel and the other is a foldable clamshell type. The clamshell speakers are
small enough to fit into my pockets. The flat panel is perfect for viewing video files in the office or home. I have
modified the clamshell speakers to plug in directly into the Pxxx phones or through the amplifier. I find the
clamshell more suitable for listening to MP3s through Unreal Player in 'flip closed' mode. The audio patch cable
attaches directly to the Pxxx and has a 3.5 mm output jack that connects to any audio device
(ie speakers,PC,stereo receiver,etc.). The headphones were generic foldable stereo headphones that I also
tweaked to attach directly to the Pxxx phones. All the above eliminates the use of an audio jack adapter. I tested
them with Unreal Player and the standard Pxxx PV player. Leisure time has now become more of a pleasurable
experience with my Pxxx series phones with these new additions.

Pics:
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4:3 (Standard) and 16:9 (Widescreen) w/ amplified stereo mini travel speakers audible in any crowded room.

great work bigfeat! I wish I could try that video out.

Here are some suggestions, but before that, I think its 2.5mm and not 1.5mm. The ordinary Jack is 3.5mm and we have the 2.5mm one.

1.) I am using a 2.5mm-3.5mm converter that I got from HK which amazingly works like a charm. Then you can use a 3.5mm-RCA cable and connect it to any stereo system with input capabilities. Problem is everytime you recieve a call you have to unplug it to take the call. Also sometimes when moving a lot I always seem to accidently activate voice dial. I think it has something to do with the mic terminal touching the adapter the wrong way that activates the voice dial.

2.) I am also have the 2.5mm-3.5mm converter with Microphone. I bought this when I had the P800. I could connect any kind of heaphones and speakers to it too and of course do the above too but I am also able to answer calls.

3.) Using any of the above adapters, you can get the Radio Tranciever accesory for the IPOD which allows you to transfer the audio from your P900/P800 to any radio/stereo/car stereo/component wirelessly via a radio frequency that you set on the tranciever device. eg: Set it to fm 88.7, then set your stereo to that frequency and voila! Actually, now I can now entertain my car passengers with a movie sound comes out on all four speakers and since I have the universal phone holder on my car, I simply twist it to landscape mode and instand LCD!

Originally posted by Muzikfreakah
3.) Using any of the above adapters, you can get the Radio Tranciever accesory for the IPOD which allows you to transfer the audio from your P900/P800 to any radio/stereo/car stereo/component wirelessly via a radio frequency that you set on the tranciever device. eg: Set it to fm 88.7, then set your stereo to that frequency and voila! Actually, now I can now entertain my car passengers with a movie sound comes out on all four speakers and since I have the universal phone holder on my car, I simply twist it to landscape mode and instand LCD!

That's a cool idea! But what Radio tranciever are you using? Not the (officialy made for Ipod) Griffin iTrip FM Transmitter, now are you? Because that one only works for the Ipod if I'm not mistaken...

Thanx Muzikfreakah. I allready own a similar device, but the only disadvantages I found to be that it requires its own batteries and that it can only broadcast on a limited amount of frequencies (two disadvantages, that Griffin device don't seem to have). But it seems that the Belkin device has the same disadvantages...😞

It requires 3(!) AA batteries, and you got 6 frequencies to choose from. But it's not as compact as your device I believe.

Hey

I'm kind of a beginner at the modifying business. I own a P900 and want to attach stereo speakers to it. Now, I know about 3,5mm vs 2,5mm plugs and all that but what concerns me is the polarity! I mean the speakers I intend to use have 3,5mm plug with 3 poles (I'm guessing Right,Left,Ground) but the telephone contact is a 2,5mm jack with 4 poles (I'm guessing Right,Left,Mic,Ground). How do I know which pole is which and what do I do with the mic since I don't have any use for it?

Best,

Bj�rn Andersson, Sweden.