Install Dual LED Flash for HTC Diamond2 camera

HTC Touch Diamond2 T5353 phone has a very good camera. It is also better than some cheap compact cameras too.
But it has no flash. So it cannot takes photo in the dark.
So I try to install flash for it.

I use dual LED AGILENT/AVAGO HSMW-C191. It costs 15 THB per each.
Advantage:
- It can uses up to 3.9 Volt maximum of power supply, which equals to Diamond2 battery. No need to drop the voltage.
Disadvantages:
- It produces less light compare to LED flash on newer camera phone.
- It produces too much purple.

I'll try to change LEDs later.

Circuit (Maybe???)



Flash was used in the totally dark place.


Flash was used.


Flash was not used.


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Repair Linksys WAG200G wireless router

Sorry. This post was not available in English.
คลิกที่ เพื่ออ่านบทความเป็นภาษาไทย

Induction Cooker

I've just bought an induction cooker from BigC. It's Hanabishi HIC-20EA 2000 watts, 1700 BHT.
My sister bought another induction cooker from Lotus for only 900 BHT. It's AJ brand. Sooooo cheap (T_T)

You can find more information about the induction cooker from Google.
http://en.wikipedia.org/wiki/Induction_cooker
http://www.google.co.th/search?hl=th&q=induction+cooker

Inside Phone Watch

Finally, The phone watch was disassembled.



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Power Amp Class-D (part 2)

I went to Baanmooh today gain.
At first I am going to buy two of Power Amp Class-D 20W
But I saw this, Power Amp Class-D 12+12W, 690 BHT.

12W+12W CLASS D Specifications 1. 12W/CH, 8 Ohms Load at 15 Vcc 2. No Heatsink 3. 32 Step DC Volume 4. Vcc 8-18 V 5. Imax 2 A at Po 12 W 6. Shutdown 160 uA

It uses digital volume control to adjust both level simultaneously.
So there will be no noise generated when the volume got dirt.

No pop/click sound generated when turning on/off power switch.
(The same as 20W.)

I have measured its power consumption:
- No sound, 15 mA
- Playing at normal level, 25 mA
- Driving SubWoofer speaker, 125 mA




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Modify Car MP3 Player (part 2)

Oops! I did it again... errr... I mean I bought it again.

A Car MP3 Player, 220 baht, with a new circuit design. (But the same crap sound quality)
So I added an antenna and 2 capacitors to add more treble.
Now its sound quality is better than some radio stations. ;-)

- Antenna, use thin wire about 36 cm. long.
Then soldered at ANT label.
(I forgot to take the photo)

- Use 2 small 0.0068uF capacitors, then soldered into the space as shown in photos.
(I found only the big one from my spare)

- Use cutter to cut the plastic filter between LCD display and infrared receiver.
(Don't know what's that filter for)




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Mini Pre-microphone

Have you ever tried to use dynamic microphone with PC?
If you have, you'll know that it won't work.
So a microphone amplifier is needed.
And I've found one at Baanmooh, it's 200 BHT, very small.
The sensitivity can be adjusted.
It can operate at 0.9 Volt 0.8 mA.
If you use a 1.5 Volt 800 mAh button cell battery,
it'll last for 1000 hours, or 41 days!!!












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Power Amp Class-D

Today I got a power amp from NPE.
It's Class-D Power Amp 20W, 665 BHT

20 WATTS CLASS D Specifications 1. 20W at 8 ohms 16 Vcc 2. No Heatsink 3. Short Circuit Protection 4. Vcc 9-18 V 5. Imax 1.3 A at Po 20 W 6. Shutdown 1 uA

Can't believe that it requires no heat sink.
I used to do 2W power amp, it's very hot and have to use heat sink.
And also can't believe that it requires only 1.5A transformer.
Most 30W power amp requires 5-6A transformer.

But when I tested it to drive a subwoofer speaker, powered by very cheap 1A transformer.
It's soooo amazing!!!
After continuous using about 4 hours, no heat generated at all. Like it's not operating.
This very cheap 1A transformer is not enought to supply the AA battery charger.
But this power amp powered by that transformer can shake my door!

Class	Efficiency
A	25% (theoretical)
AB	less than 78.5% (theoretical)
D	80-95% (practical)

(Credit http://en.wikipedia.org/wiki/Electronic_amplifier)

[Sat 11 Oct 2008]
Finally, I put my power amp class-D in an (antiquated) box.
Althought it's looked uninterested, but it can shake the room, no heat generated.





If you want a subwoofer filter, try this. Subwoofer Filter

[ดูรูปภาพทั้งหมด]

Digital Clamp Meter

I got this stuff from Baanmooh (again) a few days ago.
Digital Clamp Meter, 350 BHT.
- Contactless electrical power consumption measurement
- Digital volt/ohm meter
- Continuous measurement with sound alert

Let's do some test now.
Then you will know that you should leave it plugged-in to avoid spark,
or should un-plug it to save energy cost.

Electrical Equipmentห	Power consumption (mA)
Home theater 600 Watts (stand by)	0
Home theater 600 Watts (booting)	120
Home theater 600 Watts (running)	140-150
Lamp 20 Watts	70
HTC Touch Diamond charger (not charging)	0
Nokia charger (charging)	0
Adapter 9 Volt 1 Amp (Amorn)	0
Hatari fan (speed 1)	140
Hatari fan (speed 2)	160
Hatari fan (speed 3)	210
LCD Dell 19" (off)	30
LCD Dell 19" (on, black picture)	150
LCD Dell 19" (on, white picture)	160
PC (2 months) (off)	0
PC (2 months) (on)	39-40
Laptop Dell 12" (off)	0
Laptop Dell 12" (on, light load)	100-120
Laptop Dell 12" (on, heavy load)	150-180
Printer Lexmark All-in-One (off)	20
Printer Lexmark All-in-One (on)	20
Printer Lexmark All-in-One (Scanning)	20-30
Printer Lexmark All-in-One (Printing)	50-70

PS. "0" means unable to measure (less than 10 mA).

Oh God! LCD monitor and printer always consume power eventhough they are turned off. (=_=")
They should be added some "real" switchs.







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Onkyo HT-S3100

After looking for almost 2 years, finally I bought it.
Onkyo HT-S3100, 11800 BHT

It's a digital amplifier from Japan.
Just plug the power cord, connect all speaker cables, and S/PDIF data cable.
No more messy cable. Better sound quality.
It can also transform stereo signal into DTS NEO 6, better than Dolby Pro Logic II (I think).
Many functions are available. Also has a red lamp on remote control.
The sound quality is much better than Sony Home Theater,
but worse than harman/kardon. Maybe the system hasn't burned yet.

Tips
- Show temperature : Press DISPLAY+STANDBY buttons, then release and press TONE button.
- Show firmware version : Press DISPLAY+STANDBY buttons.
- Factory default settings : Press VIDEO 1+STANDBY buttons.
















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Modify Car MP3 Player (part 1)

I had nothing to do tonight. So I modified Car MP3 Player.
Its volume level is too low. And the sound quality is not good enought.

Here is its specitication:
- 350 BHT
- LCD display for text and graphic with blue backlight.
- Display song name in English
- Play MP3 file from SD Card (or micro SD Card in SD adapter)
- Play MP3 file from USB Drive
- Receive analog sound from line-in, such as Laptop, iPod, GPS Navigator, etc.
- Frequency selectable from 87.5-108 MHz.
- Full functional infrared remote control
- 5 presets equalizer




To improve sound quality:
A very pointed soldering iron is needed. Because the circuit is very small.
Disassemble it. Then remove 2 resisters, and 2 capacitors.
And then short the connectors of 2 resisters that were removed.
The sound will be louder and little more treble.


If you want to use it with your laptop,
then you have to supply the power via USB port, instead of car charger.
You need to find an unused USB cable.
Then connect red and black wires to the circuit.
Plug USB into laptop's USB port, and Line-in cable into laptop's headphone port.


If you want to gain the range of broadcasting,
you can connect a small and long wire to the circuit's antenna (green wire).




If you got a new one with difference circuit layout, see here.

Car MP3 Player

http://203.185.67.122/toy/blog/?p=154&langswitch_lang=en

Digital Photo Frame

http://203.185.67.122/toy/blog/?p=113&langswitch_lang=en

Screwdriver Voltage Tester

http://203.185.67.122/toy/blog/?p=98&langswitch_lang=en

Subwoofer Filter

It's my first time using Protel. I spent whole day with it.
This is the subwoofer filter for subwoofer's power amp.