LED replacement mod -Beautiful Sanyo 4920

[ZapWizard]

Hey folks,
I am a skilled computer modifier, and also a Sprint PCS Fan.
(I used to work at RadioShack)
You can check my work at www.ZapWizard.com

But onto the real reason for this post:

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-Sanyo 4920 Keypad Mod
-Replacing the dull green LEDs for brilliant white.

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http://www.zapwizard.com/mods/sprintphone/cimg0139.jpg

I recently (1 week ago) purchased a Sanyo RL-4920 Vision phone.
The phone is loaded with features and long battery life.

It also had a great color screen. But...and ugly dull, uninspired green keypad.
This needed to be fixed.

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http://www.zapwizard.com/mods/sprintphone/cimg0155.jpg

So after opening the phone, and counting the needed LEDs I ordered 12 LEDs from www.lsdiodes.com
It cost less then $10 for the LEDs needed to complete this mod. (including shipping)

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http://www.zapwizard.com/mods/sprintphone/cimg0158.jpg

Now it was time to crack the phone back open.
The phone has special Y shaped screw heads, but they can still be opened with the properly sized screwdriver.

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http://www.zapwizard.com/mods/sprintphone/cimg0160.jpg

Once open and taken apart I can remove the keypad for soldering.
There were actualy four extra solder pads for more LEDs, but they were not installed.

I installed two of the extra LEDs, as I lost one LED into my carpet.

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http://www.zapwizard.com/mods/sprintphone/cimg0162.jpg

I removed one LED and tested to make sure the orientation and power would light the white LEDs.

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http://www.zapwizard.com/mods/sprintphone/cimg0163.jpg

Once all the LEDs were replaced, they looked good.
But they were just as bright as the green LEDs.

The LEDs I ordered take 35milliamps of power, run at 3.6 volts, and have a brightness of 200MCD.

(VERY Bright for surface mount LEDs)

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http://www.zapwizard.com/mods/sprintphone/cimg0165.jpg

The solution was to calculate the correct resistor value needed to run all the LEDs in parallel. (A total of 350mA)
The resulting value was only 1.2ohms.

I decided to use a 2.2ohm resistor.

The resistor I installed is a normal resistor, and is held inside the rubber tube at the bottom of the phone.

It is just large enough to fit into some empty space next to the phone's mic.

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http://www.zapwizard.com/mods/sprintphone/cimg0167.jpg

Now the LED are running at their full brightness.
Also note, that they will run warmer, and consume much more battery power then the orignal LEDs.

The original LEDs consumed about 100mA of power total.

These LEDs consume 350mA of power.

This phone however has 1 week of standby power, and 5.5hours of talk time.

So the extra power needed shouldn't hurt the phone too much.

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http://www.zapwizard.com/mods/sprintphone/cimg0168.jpg

Here is a night shot showing the LEDs.

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http://www.zapwizard.com/mods/sprintphone/cimg0169.jpg

And another.
The LEDs are the only source of light in this image.

They are more then enough for a good flashlight.

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http://www.zapwizard.com/mods/sprintphone/cimg0174.jpg

With the phone put back together you can see that the keypad now matches the screen, both in color, and brightness.
It has increased the look of the phone considerably.

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http://www.zapwizard.com/mods/sprintphone/cimg0178.jpg

At night the keypad is clear and easier to read.
Also note the middle joy-button is now lit-up.

Where originally it was barley visible at night.

The final image is below:

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http://www.zapwizard.com/mods/sprintphone/cimg0176.jpg

[blue]

Wow...very nice.

[LoDown3]

i kno this umm...8200, that wouldnt mind having the same look on it as well :D

[Deval]

that looks so HOT!!! :D

[TRSNYPAZ]

one word: BLAZED

[Marlon_JB2]

Dude....speechless!!!! That is hot! :D

[SL10]

WOW! Great mod! The pics are so bright, I had to wear shades just to look at them! LOL!

[MsRandall]

Yep the phone is hot!!! You did a great job. Welcome to our forum too

[ncoliva]

Looks like Chi better watch out. This guy showed us all the work behind it! :hee:

[Deval]

yeah but i dont think its that easy...i saw my friend do his LG 5350, and i was like...F that...cant even solider something THAT small

[ZapWizard]

Thanks guys,

I don't plan on doing this commercialy or anything, this is my own hobbie.

It is not easy by any means, as these things are nearly the size of a grain of salt. (The resistors are probably even smaller)

I also went in and modified the phone again.
I bought the USB sync cable, which doesn't charge the phone.
So I traced where the USB +5volts went inside the phone, and soldered a wire between that trace, and the +5volt input where the charger comes in.
-The result is that I can charge the phone with either USB, or the included charger.
Something I will need as I am often on the road with a PC.

I have modified a few other cell phones before, and I will soon by overhauling my wife's Denso phone.

Here is my old Denso 2200 I modded:
http://www.zapwizard.com/cellphone/index.html

[chenyichung]

ZapWizard, that's some good work man. Also love all of your computer case mods you have on your website. I wish i had time for that kinda mods. Keep up the good work, and if you have time, you should make a tutorial, cause' i know a buncha people in here wanna give it a shot themselves. i'mma have ta try orderin' those LEDs from that website you got there. A lot cheaper than my last supplier.
oh yea, for those who wanted to order LEDs directly from my supplier, he stopped doing the LED business cause' it's not that HOT over in cali anymore, he's now into selling import rims, hehe, i dunno :) But yea, he sold me the rest of his RED, PURPLE, and WHITE LEDs, should be here tomorrow for a pretty good price, that's why i dropped the price on the LED mods i offer. But yea, if you're still interested, i'mma have a lotta RED, WHITE, and PURPLE LEDs next week, but after that, no more time for LED conversions, school's starting again.
Anyhow, just wanna give an update, ZapWizard, once again, your works lookin' real hot there. Keep it out!

-Yi Chen

[culpthug]

do you think you could help me with sumthin im workin on ????
i got a couple leds hyperwhites and hyberblues that are like 5 volts a piece and would like to know how i could get them alternating its for a police car R/C.X-mod to be exact

[ZapWizard]

Keep up the good work, and if you have time, you should make a tutorial, cause' i know a buncha people in here wanna give it a shot themselves. i'mma have ta try orderin' those LEDs from that website you got there. A lot cheaper than my last supplier.
-Yi Chen

Well, I took enough images to do a full tutorial.
(normaly my mods are written as guides)

But, my techniques are prettu ghetto, so I didn't end up finishing the guide.

But here is the text version:
DO AT YOUR OWN RISK
1: Open the phone count how many LEDs you will need.
2: Order the LEDs
3: Make note of the orientation of the old LEDs.
-Each LED should have some sort of marker to show which direction is which.
-You may need a microscope or magnifying glass.
4: Remove the old LEDs
-Do this by first masking off the entire area around a single LED with alluminum tape, or some other heat resistant material
-Get a grip on the existing LED using tweezers
-Using a heatgun heat up the solder around the LED until the LED easily moves off the pad.
-Be very careful NOT to rip off a solder pad, or resistor.
5: Solder the new LEDs in place.
-Make sure and solder them with their orientation marker in the same spot as the old LEDs
6: Test the LEDs
-If they don't work, then you screwed up somewhere, or they are backwards.
-Removing LEDs of this size also destroyes them, so don't count on doing it twice.


Things I did that I don't recommend everyone try:
-I used a mini-torch instead of a heatgun, this made the old LEDs melt as I removed them.
-I tested the LEDs orientation by pressing them to the solder pads using the tweezers. This is dangerous as the tweezers could cause a short.

If you can get the keypad out of the phone, away from the LCD and other electronics, then do it.
Look over the entire PCB and take lots of notes and drawings, or better yet good photo's before you start removing parts.



do you think you could help me with sumthin im workin on ????
i got a couple leds hyperwhites and hyberblues that are like 5 volts a piece and would like to know how i could get them alternating its for a police car R/C.X-mod to be exact

You need a LED flashing circuit for that.
You can search google for circuits, and kits that can do that.

[G-Unit_4900]

hey, what school did you go to and what degree do u have?, im goin 2 school studying cpu-enginneering to do stuff you do for fun. im currently @ bradley university. Any advice for an up and comming engineer? how'd u land a job @ amd? what salary range are they payin ya? (ballpark) sorry if u feel im nosy just real interestd in engineering and the engineers.

[ZapWizard]

Well, beleave it or not, I don't have a degree yet.
I am a technican, with classes from the local community college (Good community college though)

Advice: LOTS of math. (Hence why I am not an engineer by now)

I landed an Intership at AMD in high school, through a dual-credit electronics class.
Later I got in as a technican, as a supervisor was in one of my classes.

I am currently switching to marketing though.
As far as salary as a tech, it's pretty average, but not great.

[SPRINTSUCKS123]

HEY MR. ZapWizard

HOW MUCH WOULD IT COST ME IF I BOUGHT THE AMMO COMPUTER FROM YOU >



THAT THING IS FREAKING AWSOME > > > > > >

[ZapWizard]

HEY MR. ZapWizard

HOW MUCH WOULD IT COST ME IF I BOUGHT THE AMMO COMPUTER FROM YOU >

THAT THING IS FREAKING AWSOME > > > > > >

Sorry, I am not selling it, as it was my first big project.

[tlhop911]

hey zap wizard how much would you charge to do a led mod on my 8200? my brother lives in Austin so i could send it to him and he could get it to you

[wolfsoul]

Hello i was wondering if u can tell me where do u plase the resistance in ur phone i have mod my 8200 and i notice the extra space for the LEDs ans I wanted to look much brider but i haven't find the way i notice that u put 1 of the pins of the resistance in the negative of the LED but where do u put the other 1?
thanks
:confused:

[Guy]

Wow, I missed this thread before. That mod job you did on the phone is awesome. I tried checking out your website to see your other work but it appears to be unavailable.

[suprdav2]

man, that looks so sweet. That's how the 4920's should have looked in the first place, instead of these dull green LED's.

-- Dave

[Jaggrey]

That looks sweet man!

I just got my degree in Computer Engineering in May :) There was a whole lot of math, but it wasn't too bad. Now I wanna do something more in IT tho.

[ZapWizard]

hey zap wizard how much would you charge to do a led mod on my 8200? my brother lives in Austin so i could send it to him and he could get it to you
I am too busy to do them on the side.
This is can be done by anyone able to solder well, the resistor replacement is totaly optional.

Hello i was wondering if u can tell me where do u plase the resistance in ur phone i have mod my 8200 and i notice the extra space for the LEDs ans I wanted to look much brider but i haven't find the way i notice that u put 1 of the pins of the resistance in the negative of the LED but where do u put the other 1?
thanks
:confused:
As above the resistor replacement is totaly optional. It just makes it brighter, as the new LEDs can handle more power.
In my phone all the LEDs were wired in parallel off a single power source. Each LED had it's own tiny resistor.
I calculated the resistor needed to power all the LEDs off a single larger resistor. I then shorted the existing resistor out. (Wireing the LED directly to full power) I then used an exacto-knife to cut the trace powering the LED in half, and wired the new resistor in to complete the circuit.
If this doesn't make sense to you, find a friend who knows electronics.

[wolfsoul]

I am too busy to do them on the side.
This is can be done by anyone able to solder well, the resistor replacement is totaly optional.


As above the resistor replacement is totaly optional. It just makes it brighter, as the new LEDs can handle more power.
In my phone all the LEDs were wired in parallel off a single power source. Each LED had it's own tiny resistor.
I calculated the resistor needed to power all the LEDs off a single larger resistor. I then shorted the existing resistor out. (Wireing the LED directly to full power) I then used an exacto-knife to cut the trace powering the LED in half, and wired the new resistor in to complete the circuit.
If this doesn't make sense to you, find a friend who knows electronics.


thanks man is ok im a geek as well so i know what u talking about thanks for the info :cool:

[MD-80]

Love the way those white LED's look

[Deval]

this thread is over 2 years old

[MD-80]

Great, was looking into doing it for my sisters 8300 and found this

[PrincessPixie]

That is so very sexy!

[pcsperson]

Dude....speechless!!!! That is hot! :D
What he said. Very nice work

[MD-80]

Allright, so I'm not the only that can apreciate a 2 year old thread

[reemusk]

Love the way those white LED's look



are you kidding?! this is from 04!!!

[MD-80]

Still like the way they looked though

[wolfsoul]

lol I remember this post
in the end I did change the led for 4 phones
1 - 5350
3 - 8200
Good old times

[MD-80]

Has to be a pain to do it though

[wolfsoul]

not really I got a lot of practice :)

[MD-80]

Takes soldering skills I probably don't have though.

[wolfsoul]

lol well it thats!!

[stephpcs]

I ENJOYed this thread. it made my 'dream' is always someone elses reality! i always wondered if this could be done and now i see it can and has!! def somethin to look back on or even try to continue to inspire to do

[wolfsoul]

well I write a little tutorial with some picks and stuff like that
http://www.sprintusers.com/forum/showthread.php?t=54382&page=1&pp=15&highlight=sanyo+8200+mod

[MD-80]

Thanks!