Boost the range of your Monster iCarPlay
I love my iPod. Having virtually all of Motorhead's catalogue at hand is a darn good thing.
Back in December I was in the market for one of those adapters which would let me listen to the iPod in the car. I found the Monster iCarPlay. You know Monster, they're the people who make grossly overpriced cables for suckers called "audiophiles".
The transmitter worked fairly well but there was some static and drop-out while driving around. A few times I've had other people with similar transmitters override my own unit. "Why don't you change your station?" Because I own 88.1 MHz! One instance a couple of weeks ago stands out: the jolt of going from GG Allin's Be My Fuckin' Whore to some Top-40 dance crap nearly killed me. That's when I decided to remedy this.
All in all, this should take you no more than ~15-30 minutes. It took me about half an hour and I was doing it from scratch. I didn't think to take pictures before doing this so you're getting photos of the end result here.
What You'll Need
- Knife
- Soldering iron, solder
- Wire (I used a ~50 cm piece of plain ol' Cat-5 twisted pair which IS NOT IDEAL, see below.)
- Fort Garry Dark Ale
DISCLAIMER
This will void your warranty, I'm not responsible for whatever happens, blah blah blah.
1) Open the iCarPlay
This is easy, use a butter knife and gently pry the top and bottom halves apart. Mine came apart with absolutely no problem at all.
2) Locate the antenna
On one side of the board you'll find a small wire perhaps 4 cm long. It will be soldered to two pads labelled J10 and J11. Remember this is the finsihed product, this picture shows the pads after I've completed step 4.
3) Cut a new antenna
Ideally your antenna would be 1/2 or a full wavelength of the frequency you plan to transmit on. It's a simple calculation: speed of light / the frequency or c/f . So for my case: 300 000 000 / 88 100 000 = ~3.405 meters.
Even at a half wavelength, 1.7 meters will give me an antenna almost as long as I'm tall. You can go shorter, recall the original antenna was just 4 cm long and doesn't appear to be loaded with a coil (to emulate a longer antenna). FM transmits in doughnut shaped pattern: if you can mount your transmitter vertically, you'll get the best overall coverage. If you have the option of going with thinner or thicker copper for your antenna, go thicker.
Take the time to experiment with a portable radio and various lengths of antenna. The results will be worth it.
4) Replace your old antenna
Desolder the old antenna wire and toss it, unless you really need that 4 cm of wire around the house. Solder one end of your new antenna to pad J10. Pad J11 is useless, you don't need to use it unless you want to have a loop of wire for whatever reason (I did for testing). Ensure that you haven't shorted anything out with wayward solder.
5) Carefully cut a notch for the antenna
In the black backing of the unit you'll need to cut a small notch for your new antenna to pass through. The hole I show here needed a bit of tidying up.
6) Reassemble the unit
It's straight forward but watch for the alignment of the red frequency-selection button. It has 4 key notches on it but they aren't symmetrical. Notice how the one that the one you'd expect to be at 3 o'clock in this picture is actually around 4 o'clock.
Pass the antenna through the hole you cut in #5 and with a short piece of electrical tape secure it to the iCarPlay's cable so there isn't much play with the wire inside the unit. The rest can dangle.
The unit will need some SuperGlue to go back together. Being that I was still testing mine I just used a couple of zipties to hold the thing together while I was testing it in the car.
7) Results
So far it's been almost perfect. I've had very little static, no drop-out, and no override from others (what this does to others I don't know :)). There's one intersection here where my unmodded unit always had a lot of trouble (East bound Portage and Maryland for you Winnipeggers out there) This has completely remedied that problem. In a walking test with a portable radio, static started to affect the sound around the 15 meter mark from the car. That's cool.
8) Enjoy!
Feel free to post your comments/gripes here.
g
Back in December I was in the market for one of those adapters which would let me listen to the iPod in the car. I found the Monster iCarPlay. You know Monster, they're the people who make grossly overpriced cables for suckers called "audiophiles".
The transmitter worked fairly well but there was some static and drop-out while driving around. A few times I've had other people with similar transmitters override my own unit. "Why don't you change your station?" Because I own 88.1 MHz! One instance a couple of weeks ago stands out: the jolt of going from GG Allin's Be My Fuckin' Whore to some Top-40 dance crap nearly killed me. That's when I decided to remedy this.
All in all, this should take you no more than ~15-30 minutes. It took me about half an hour and I was doing it from scratch. I didn't think to take pictures before doing this so you're getting photos of the end result here.
What You'll Need
- Knife
- Soldering iron, solder
- Wire (I used a ~50 cm piece of plain ol' Cat-5 twisted pair which IS NOT IDEAL, see below.)
- Fort Garry Dark Ale
DISCLAIMER
This will void your warranty, I'm not responsible for whatever happens, blah blah blah.
1) Open the iCarPlay
This is easy, use a butter knife and gently pry the top and bottom halves apart. Mine came apart with absolutely no problem at all.
2) Locate the antenna
On one side of the board you'll find a small wire perhaps 4 cm long. It will be soldered to two pads labelled J10 and J11. Remember this is the finsihed product, this picture shows the pads after I've completed step 4.
3) Cut a new antenna
Ideally your antenna would be 1/2 or a full wavelength of the frequency you plan to transmit on. It's a simple calculation: speed of light / the frequency or c/f . So for my case: 300 000 000 / 88 100 000 = ~3.405 meters.
Even at a half wavelength, 1.7 meters will give me an antenna almost as long as I'm tall. You can go shorter, recall the original antenna was just 4 cm long and doesn't appear to be loaded with a coil (to emulate a longer antenna). FM transmits in doughnut shaped pattern: if you can mount your transmitter vertically, you'll get the best overall coverage. If you have the option of going with thinner or thicker copper for your antenna, go thicker.
Take the time to experiment with a portable radio and various lengths of antenna. The results will be worth it.
4) Replace your old antenna
Desolder the old antenna wire and toss it, unless you really need that 4 cm of wire around the house. Solder one end of your new antenna to pad J10. Pad J11 is useless, you don't need to use it unless you want to have a loop of wire for whatever reason (I did for testing). Ensure that you haven't shorted anything out with wayward solder.
5) Carefully cut a notch for the antenna
In the black backing of the unit you'll need to cut a small notch for your new antenna to pass through. The hole I show here needed a bit of tidying up.
6) Reassemble the unit
It's straight forward but watch for the alignment of the red frequency-selection button. It has 4 key notches on it but they aren't symmetrical. Notice how the one that the one you'd expect to be at 3 o'clock in this picture is actually around 4 o'clock.
Pass the antenna through the hole you cut in #5 and with a short piece of electrical tape secure it to the iCarPlay's cable so there isn't much play with the wire inside the unit. The rest can dangle.
The unit will need some SuperGlue to go back together. Being that I was still testing mine I just used a couple of zipties to hold the thing together while I was testing it in the car.
7) Results
So far it's been almost perfect. I've had very little static, no drop-out, and no override from others (what this does to others I don't know :)). There's one intersection here where my unmodded unit always had a lot of trouble (East bound Portage and Maryland for you Winnipeggers out there) This has completely remedied that problem. In a walking test with a portable radio, static started to affect the sound around the 15 meter mark from the car. That's cool.
8) Enjoy!
Feel free to post your comments/gripes here.
g
9 Comments:
Awesome!
It works freakin awesome! Thank you!!!!
This works great.
Thanks for the info!
Hey grub!
Saw this link on /. on the weekend. Tried it out and I'm transmitting at least 50' from my car now.
Fucking cool top, thanks bud!
Anybody try this with the icarplay plus? I opened mine up and it looks a lot different and there was no 4cm antenna just sitting on the inside.
Mike:
If you don't have a wired antenna, it may be a length of copper trace directly on the board.
Look for a transistor with one leg going to the trace (or wire) and nothing else. The trace (or wire) will probably have nothing else connected to it.
Could you put up a JPG somewhere (or email it to me) of the circuit board?
mail it to blog at grub dot net
This sounds cool. Anyone know if you can mod the Kensington Digital FM transmitter for iPod? Mine often gets killed by power lines and local stations.
Grub: if you like i can open it up and send you some pics, for some mod advice.
So after reading your blog i went over to hackaday.com to see what they had in their iPod hacking archive and found this little gem for the iTrip
Why isn't cat 5 ideal? Because it's thin?
Anyone able to figure out the iCarPlay Plus? I can post a circuit board photo if it hasn't already been done.
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