.:Info
Nick: akeeh  Info
Age: 30
Location: Tampere

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User info:
Full name: Aki Korhonen
Homepage: http://www.akikorhonen.org/
Age: 30
Location: Finland, Tampere
Bio:
AK^ @ IRCnet



Title: Projector mount
Created: 06.11.2010 13:58

Friday's quick project, a projector mount from a few pieces of scrap aluminum and an old video camera tripod head.

I've had the video camera head sitting in the shelf for a long time as I purchased a ballhead a couple years ago which is much better suited for photography. Now I re-purposed it to a sturdy projector mount.

I don't use a ceiling lamp so I just attached the mount to where the lamp would go and took the electricity from the same place so I can now turn the main power off from the wall switch.

At the moment I'm running the video signal to the projector via my VGA to RJ45 -adapters and some network cable until I get a long VGA cable as there is a little bit of ghosting visible on the picture (or maybe the network cable is bad, I don't remember was there any ghosting when I last used the adapters).
Friday's quick proje...
Friday's quick project, a projector mount from a few pieces of scrap aluminum and an old video camera tripod head.

I've had the video camera head sitting in the shelf for a long time as I purchased a ballhead a couple years ago which is much better suited for photography. Now I re-purposed it to a sturdy projector mount.

I don't use a ceiling lamp so I just attached the mount to where the lamp would go and took the electricity from the same place so I can now turn the main power off from the wall switch.

At the moment I'm running the video signal to the projector via my VGA to RJ45 -adapters and some network cable until I get a long VGA cable as there is a little bit of ghosting visible on the picture (or maybe the network cable is bad, I don't remember was there any ghosting when I last used the adapters).
Friday's quick proje...

Title: Electronics
Created: 28.08.2010 13:27

Transmitter and receiver pair for one upcoming project. The longer one is the receiver and the connector is a 9-pin D-sub. I used 433MHz transmitter and receiver set from SparkFun and both of the "motherboards" I made for them contain an ATtiny2313.

More info coming after I get some software done for both of the boards.

Board dimensions:
Transmitter: 24mm * 33mm
Receiver: 24mm * 49mm (62mm with the connector)
Transmitter and rece...
Quickly made galvanic isolator between the DVB-C box and antenna cable. Removed the 50Hz hum from speakers and signal quality of the broadcast is still around 90% so no problems with picture either.

Very cheap and efficient way to break down the ground loop causing the hum. Only two connectors and two 10nF 250-400V rated capacitors. I made the box from small pieces of PCB and soldered all of them together to form a RF-shield to the inside and a sturdy box. Note that the other connector's body isn't connected to the box frame!

Schematic borrowed from here:
http://www.tkk.fi/Misc/Electronics/circuits/antenna_isolator.html
Quickly made galvani...
The 7" screen panel from Joytech Ultimate Travel Pack for Xbox stuffed inside a Lacie Porsche external HDD casing.

More info and a project log in english coming soon. For more photos, visit Metku.net's forums (text in finnish):
http://metku.net/hwforum/viewtopic.php?t=6458
The 7" screen p...

Title: Random
Created: 28.08.2010 13:26

I finally built a projection screen for my video projector. The aspect ratio of the screen is 16:9 and the size is 85" diagonal (188 cm wide and 106 cm high).

The frame is made of 21mm*21mm wood which was then covered with black fabric. Then I stretched a white cloth to the frame and a black cloth on top of that so light doesn't get through. All the fabric pieces were attached with staples and I think I used over 300 of them.

I might do the screen of a piece of MDF painted with the suitable color later, but this is better than nothing for now.
I finally built a pr...
Quick test with two projectors and projected pictures (almost) seamlessly aligned side by side. Little bit of color variation between the projectors because of different lamp usage times. The little screen between the projectors is Nokia N800 that I used as a VNC client to control the computer while testing.
Quick test with two ...
Today's shoppings ;)
Got two of them very cheaply (one is going to my parents maybe) with a lot of hours to go with the light bulbs inside. The third one is broken (freebie), but a good source for spare parts for the working ones.
Today's shoppings ;)...
Operation tidy-up-the-wires. I did some new arrangements to my apartment and after that I decided to tidy up all the wires going to the TV-stand, AV-amps and speakers. Took a couple hours but it was worth it. Looks nicer and eases up cleaning.

The upper AV-amplifier is that way because it is for the speakers on my computer table on the right and the lower one is for surround sound when watching movies etc from the computer via TV.

The thing on the cables is spiral wire loom.
Operation tidy-up-th...
New gadget that I bought last week. I know that N810 would be nicer with its built-in keyboard but the price difference is so big so I don't want to pay so much extra for almost just a keyboard. Nicer thing with 800 is that it has two normal sized SD-card slots where 810 just has one miniSD-slot.

The direction of the USB-port on the device is switchable so it can work as a host: USB-keyboards and memory sticks can be attached.
New gadget that I bo...
I engraved this space invader creature on the back of my 
Nokia 6230 with a Dremel Engraver during the Metku.net Dremel workshops at Assembly '08.
I engraved this spac...
I've had this idea in my mind  for a long time now and happened to get a few 10-packs of new unused disks for free yesterday so I decided to give it a try. It took about half an hour to put them on the wall with little pieces of double sided tape and 46 disks were used for the figure. It might look nice if there were a white backlight behind every disk.. Maybe someday. ;)
I've had this idea i...
Quick few hour project to get some space on the desk. It is a little shelf for little stuff like the external HDD and network switch etc.

Height: 33,5 cm | Width: 19,5 cm | Depth: 19,5 cm

32 nuts, 28 washers, 128 cm of M10 thread rod (4 x 32 cm). The wood is 18 mm thick and is finished with a cherry colored wood wax (same stuff that I used on the bed frame behind it) to give it some look (nice stuff because it doesn't smell so it can be applied indoors, is non-toxic  and it dries very quickly).
Quick few hour proje...
Just a quick test project I made yesterday while visiting my parents here at home. Found this funny instructable of a DIY cotton candy machine (http://www.instructables.com/id/cotton-candy-machine/) and had to give it a try, so here it is.

The bottom part is cut from a compressed air spray can and it has a hole in the middle of it where is a M3 bolt for connecting it to the motor (visible in the photo). Then I made lots of holes with a sharp screw and a hammer. The top part is from a drink can because it had a good and tight fit when pushed on the bottom part. Hole is on the middle to feed sugar inside the thing. Heating is made with that mini torch.

It works like this: The sugar is fed inside the rotating thing and the mini torch will start to melt down the sugar. The motor rotates the chamber and the centrifugal force pushes the melted sugar out from the holes with a good speed and produces some sugar fibers you then collect with a stick.

The performance of this first test version wasn't very good, because the sugar I used wasn't maybe the best for this purpose and the holes on the rotating chamber were maybe a bit too big, so the sugar splatters were too big. Maybe I'll try to do a better one some day. :)
Just a quick test pr...
Since everyone seem to be freezing their money, so...
Don't take too seriously, couldn't resist. ;)
Since everyone seem ...
Part of my room made with SketchUp and almost everything is measured with 2-5mm accuracy. :)
Part of my room made...

Title: Robot hand
Created: 28.08.2010 13:26

SketchUp plan for my robot hand project I'm working on. There will be five normal sized servo motors and two mini servos. The fifth normal servo is under the translucent round piece for sideways rotation. There are two servos for the first joint because the biggest amount of torque is needed at that point. Maybe I'll find a high-torque servo for that later, dunno, I only have normal ones at hand at the moment.

The whole thing will be controlled with my own servo controller. You'll get more information about that from my website:
http://akikorhonen.org/projects.php?action=view&id=64

The servo controller is attached to the serial port on the PC (or serial->usb adapter) and I already programmed a small graphical software in Java to control the robot arm via the servo controller.

I'll post some photos after I get some of the parts done, stay tuned. :)

Update 24-05-2008: I spiced up the model with SketchyPhysics -plugin and took a video of the arm in action: http://www.youtube.com/watch?v=d2OBCpbCEc4
SketchUp plan for my...

Title: Rotating LED display
Created: 28.08.2010 13:25

Small upgrade for my rotating LED POV display. I did some changes to the original IR link setup and removed the optical wire from the threaded rod and ran wires for a photo transistor that I placed on top of the rod.

Now the IR serial link works very nicely and I made a little drawing program to test it out. Watch a short video clip of it in action:
http://www.youtube.com/watch?v=pfWWW_XBn-E
Small upgrade for my...
My rotating led display project. It has 16 two color leds (red+green) so possible colors are red, green and orange/yellowish (both red and green on at the same time). So vertical resolution is 16 pixels and horizontal depends on the image, the "hello" image is 36 pixels wide.

Read the whole story from my website:
http://akikorhonen.org/projects.php?action=view&id=216

Video clip:
http://www.youtube.com/watch?v=CVOgsUOslMs

I'm possibly taking this to the Assembly '08 event so look around if you can spot it. Maybe a bit hard in the big hall, but I'll try to get it to display something easily noticeable. :)

Edit: Video clip taken at Assembly '08:
http://www.youtube.com/watch?v=Zvm4PqDtXkI
My rotating led disp...

Title: Computer stuff
Created: 28.08.2010 13:24

Second problem with installing the Accelero GPU cooler to my 8800 GTS was that the card didn't start up without any RPM pulses from a fan connected to the fan connector on the card.

After some searching I found that the fan connector pinout is the same that is used in new PWM controlled CPU coolers so I cut the connector and wires from an old GPU fan (from my broken 8600) and soldered a bigger 4-pin connector (the pinout is the same, just matched the wire colors and that was it) to the other end to make an adapter where I could plug in a 4-pin CPU fan or just a normal 3-pin fan to get an RPM pulse to the card.

I used an Intel stock cooler to test the system and it worked well (the PWM controlling worked also) and the card powered up finally. That was just a test setup and at the moment I'm just taking the RPM signal from a case fan to get the card running and there is a separate 12cm under the card to cool it down.
Second problem with ...
I finally installed the Accelero GPU cooler to my 8800 GTS (XFX AlphaDog) and ran into a little problem with cooling all the voltage regulators as the tape in the little memory heatsinks didn't hold very well anymore as I took them off from elsewhere.

So I figured out that I could do a holder from some aluminum sheet and bolt it to the holes around the chips. I drilled some large holes to the places where the heatsinks would be so that the air could get through well. The standoff sticking out of the aluminum piece is for one lonely voltage regulator to get some heat out of it too.

The piece holds the heatsinks well in place and there isn't any worry of them dropping down on their own. The brownish tape in the photos is Kapton tape (very heat resistant tape) to prevent any accidental shorts to component legs etc. Just to be safe.
I finally installed ...
VGA to RJ45 -adapters. I had a need for a longer video cable so I could put my video projector where I wanted but didn't feel like buying an expensive long VGA-cable. I knew that it is possible to run VGA-signal across a CAT-5 cable and found ready masks for a PCB for the adapters.

I butchered the VGA- and RJ45-connectors from a couple of old ISA network cards and PCI video cards so it was quite cheap project to make. The adapters work very well and at the moment I'm using it with a 5 meter network cable and I don't see any interferences in the picture.

The PCB masks can be found here:
http://www.geocities.com/dougburbidge/vgaovercat5.html
VGA to RJ45 -adapter...
Got new coolers for the computer yesterday and spent few hours tuning the case (replaced the front fan to a bigger one and relocated the hard disks). The hard disk frame is done from a piece of aluminum plate and the front fan is running at 7 volts.

The Accelero is passive at the moment because it keeps the 8600 quite cool. Idle temperature is staying at about 37C and after an hour of CoD4 with high settings it didn't get over 46C. CPU is idling at about 32C and stressed with superpi it doesn't seem to get over 40C. I'm quite pleased that the components are staying cool and the computer is now very silent. :)

Also check out the timelapse video that I made about the install of the Accelero for the 8600GTS. I made it just for fun and wanted to try out the intervalometer function in my camera:
http://www.youtube.com/watch?v=zaGrRnd-d2I

-----------------------------

My rather low budget machine:

CPU: Intel Dual Core E2140
Mobo: ASUS P5GC-VM
RAM: 2 * Kingston 1GB 667MHz DDR2
HDD1: Seagate Barracuda 7200.10 320GB SATA2
HDD2: Western Digital Caviar WD3200JB 320GB IDE
GPU: Foxconn GeForce 8600 GTS 256MB
PSU: Nexus 350W

CPU cooler: Sharkoon Silent Eagle CPU cooler
GPU cooler: Arctic Cooling Accelero Rev.2

The case is just a normal ATX case I got for free. It is just a temporary case until I get the time, money and materials for a custom case that has been in my mind for a long time now.

[Edit 06-03-2008] 3DMark03 scores: 17111 marks (10k marks more than my previous setup)
[Edit 08-03-2008] 3DMark06 scores: 5300 3Dmarks | SM 2.0: 2400 | SM 3.0: 2260 | CPU: 1402
Got new coolers for ...
USB memory in a shell casing. I first tried it with the normal connector and didn't come out so nice so I decided to change the connector. I took the connector from an old printer pcb I had lying around and soldered it in place. The tape on the top middle picture is just for some insulation.

The shell casing is from a 12.7mm (.50") caliber anti-aircraft machine gun NSV-12.7 (I got a training for it when I was in the army so that is why I have it). Great fun to try to shoot down an RC plane with it :)
USB memory in a shel...

Title: Photography stuff
Created: 28.08.2010 13:23

Better photo with the camera attached to the holder. I also tested how it would hold the big DSLR and it felt quite ok, but I'm not going to use it like that anyway. Tested it like that just for fun and to see what would it look like :)

Took some more video clips and I'm going to upload some of them and I'll post a link then.

First video test from last night: http://www.youtube.com/watch?v=p4qFmy-e81E
Better photo with th...
I built a camera holder to my bike for my Canon Ixus 80IS mainly just for fun and to get some biking trip videos or what comes to mind. It was supposed to be just a simple holder but once again things got a bit over-engineered :) Little bit of refining has to be done on the springs but good for now.

The brownish thing on top of the aluminum is some cork mat that I cut to be under the camera so it stays nicely in place after the screw is tightened. The bent thick steel wire in the back is used to position the angle of the holder and to give some support to the back side of it. The holder has some offset from the center so that the lens of the camera is in the middle and in same line with the front tire etc.

I went out for a test ride with it after I got it finished. It was already quite late at night so the video isn't the best possible. I'll post a couple more photos tomorrow maybe and a day time video test if it doesn't rain.

Night video: http://www.youtube.com/watch?v=p4qFmy-e81E
I built a camera hol...
Happy New Modding Year to everyone from me too!
Happy New Modding Ye...
DIY panorama bracket for my camera. With this the turning axis is about where the first lens element is on the lens so it helps in panorama photography.

The bracket is made out of two pieces of 5 mm by 40 mm aluminum, the bent part is 24 cm long and is bent at the middle. The straight part is about 15 cm long. After finishing I covered both of the parts with hockey tape to give it a nicer surface so it wont feel so cold when using without gloves outside when it is cold there. Total cost was maybe around 3.
DIY panorama bracket...
More DIY photography stuff, this time a better version of the off shoe flash cord I did last year.

I wanted a flash cord for my camera that would have all the four pins to get all the information between the camera and the flash to go right. I didn't want to pay about 60 for a commercial one that has just two connectors and a cable so I decided to make it myself. The commercial one looks like this:
http://www.paramountcords.com/prodimages/shortsc28.jpg

First I started by cutting and shaping a piece of 1 mm thick aluminum to get a body for the flash shoe and after that I started building the connection part of it on a prototyping board (dot coppered). After all that was done I assembled them together and filled the hole thing with hot glue to give it some strength (I could have used epoxy for better strenght but didn't have any at hand). The tripod mount is done from a 4 mm thick piece of aluminum and then drilled and threaded.

Camera side of the thing is done from various pieces of plastic superglued together. I got the springs and studs from an old flash shoe adapter.

The connectors are PS/2 connectors (or mini-din, used in keyboards etc). I left the cables that short because I can use a normal PS/2 extension cable with this. Cost for this project was 0 (all the material I used were found by looking around the apartment) so now I can use the saved money to something else useful. :)

Bigger photo here:
http://flickr.com/photos/akeeh/2098252889/
More DIY photography...
Macro photo of 486's core. The size of the area on the photograph is about 2mm*3mm (so the text "80486" is very small, less than 1mm wide). Photo for the test competition.
Macro photo of 486's...
This is my FlashSyncBox what I built almost all the day yesterday. I can connect up to four external flashes to it (the four blach RCA-connectors on the back) and then connect the box to my camera (the red RCA-connector on the front) so every flash will fire simultaneously. I can also connect other triggers to the box instead of a camera (a sound trigger for example). This will help me with my photography hobby because now I can light things up more creatively. The box with a sound trigger would be excellent when taking high speed photos, like an air balloon exploding for example.

First I designed a pcb for the box and then printed it on a transparency sheet to use it as a mask when exposing an uv sensitive pcb plate. After that I developed and etched the board and soldered all the parts to it. I used an empty 2.5" USB HDD case as a case for the board because I had it lying around without any other use. I cut about 2cm off from it to make it a bit smaller. The device gets its juice from the 3V lithium battery inside it or from an external power supply (the power switch toggles between those two).

Dimensions: width 75mm, height 13mm, depth 105mm (124mm with connectors).
Front of the box: A test button to see if the device works (every connected flash should fire when this is pressed), sync connector (camera or other trigger), power switch (left: internal 3V lithium, right: external power), external power connector (3-6 VDC).
Back of the box: Connectors for four different flashes, can be a new flash with low trigger voltage (4-10V) or an older flash with high trigger voltage (100-250V, maximum is 600V as the thyristors I used are rated at that).

Schematic, board mask and bigger pictures can be found at:
http://akikorhonen.org/varasto/flashsyncbox/
This is my FlashSync...
Bigger view: http://finhost6.futuron.fi/~akikorho/varasto/huonepanorama_23092007_iso.jpg

Started my studies in another city and moved to my own flat, so here is a panorama shot of it. Outside of the picture there is the door of the "french balcony" on the left, kitchen behind me and the light blue door on the right leads to the lobby and there is the toilet, a clothes closet and the way out etc. The bunk is self made from scratch to fit nicely in the alcove and there is my building desk under the bed. I'll post a desk shot later.
Bigger view: http://...

Title: Model rocket 1
Created: 28.08.2010 13:21

I made fins for my model rocket project from 2mm plastic. I rounded all the top edges and sanded a blade like edge on the bottom to get an airfoil to minimize drag. All the surfaces are finished with water sanding up to a 1200 grid paper so they are very smooth.

Motor mount and parachute material can be seen in the bottom middle photo.

Bigger photo:
http://www.flickr.com/photos/akeeh/4432663592/
I made fins for my m...
Now something very different.. Model rockets.

I participated to a model rocket course to get myself a rocket license so I can buy and use rocket engines (license is needed due to the Finnish laws and restrictions on explosives and stuff). I'm now building my first model rocket for the course flight (course includes a small theory examination and a course flight) and it's coming together quite nicely.

I made the nose cone from a vitamin tablet tube by cutting the shape as a crown and then I filled the gaps with some quick 5min epoxy glue and then a lot of filing and sanding to get the final shape.

I covered the body tube with a thin layer of epoxy to harden it up and I'll sand it down next and repeat the procedure maybe ones or twice to get a good surface.

After I get some more practice on building these rockets I'll lauch a cheap pen video camera with one up to the sky. :]

More to come..

Bigger photo:
http://www.flickr.com/photos/akeeh/4408458057/
Now something very d...

Title: Blaster
Created: 28.08.2010 13:20

The display for the blaster is now finished, not much to do anymore. Next I'll have to find some red acrylic to go in front of the display to increase the contrast and to hide it. Also the top part of the blaster needs a proper lid and some  little things have to be done here and there.

Tech specs:
- Six 7x5 led matrix modules (gives a total resolution of 7x30)
- Five 74HC595D shift register chips to drive all the led modules, I only need 3 wires from the microcontroller to control the whole display

Old video with a test display (resolution only 7x17):
http://www.youtube.com/watch?v=VpbQddALv4o
The display for the ...
The display for the blaster is now finished, not much to do anymore. Next I'll have to find some red acrylic to go in front of the display to increase the contrast and to hide it. Also the top part of the blaster needs a proper lid and some  little things have to be done here and there.

Tech specs:
- Six 7x5 led matrix modules (gives a total resolution of 7x30)
- Five 74HC595D shift register chips to drive all the led modules, I only need 3 wires from the microcontroller to control the whole display

Old video with a test display (resolution only 7x17):
http://www.youtube.com/watch?v=VpbQddALv4o
The display for the ...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Blaster project, most of the work was done mainly last week. There are some things left to be done with the control panel (on top of the box) as it needs a lid and electic work needs to be done better.

Specs at the moment:
- 41 cm wide * 15 cm deep * 23 cm high
- Frame made from 6.5 mm plywood with some weight reducing routings, some pieces made from 4mm plywood
- Front aluminum is 0.7 mm thick and side aluminum panels around 1.5 mm thick
- 2x Visaton BG17 drivers (6.5 inch, 93 dB/W)
- 2*15W TA2024 amplifier (might upgrade to 2*25W)
- 10x 2500 mAh AA cells (might add 2-4 more if amplifier upgrades to 2*25W)
- Built-in MP3/WMA player with USB port and an SD/SDHC/MMC card slot
- Self made preamplifier and microcontroller (monitors battery voltage and controls the display etc) board
- Will have a 15 cm * 8 cm * 3 cm space under the top lid for an external music source (phone, MP3 player...)
- Will have a 7*30 dot LED matrix display on the front after I get the control pcb done
Blaster project, mos...
Video: http://www.youtube.com/watch?v=VpbQddALv4o

Control board for my blaster project. The board that has an ATmega8L and a double opamp for preamplifying the input signal to two different places (ATmega's ADC input and an output for the power amp).

The microcontroller is mainly used for visualizations and other stuff and it uses ADC to measure battery voltage, volume (position of the potentiometer) and audio signal. So far there are few different options for the display: Game of Life with timed steps, Game of Life with stepping by a amplitude treshold and it also spawns gliders on a spesific amplitude level to keep the show going. Other modes are audio wave, amplitude bar, volume level and battery voltage.

For testing I used an LED belt buckle (7x17 leds) and the final display will have six 8x8 LED matrix modules (8x48 leds) for a bigger display.
Video: http://www.yo...
The preamplifier and microcontroller board for my blaster. I did this board about two months ago and now I remembered to upload a photo here.

http://allthemods.com/userinfo.php?userid=10&id=7019

At the moment it only functions as a preamplifier in the temporary miniblaster but in the final blaster the microcontroller part will handle some visualization, battery voltage measuring and some other stuff.

The solder kinda looks messy, but every random looking solder spot is a via between the top and bottom side of the board to connect the ground layers together. Also the area of the operation amplifier looks messy but there are a bunch of SMD resistors and caps around it but they are hard to see from the photo.

Left photo: on the top of the board is the 5V voltage regulator, on the left side there is an Atmel ATmega8L and on the right a random dual operation amplifier to amplify the input signal with two different adjustable gains. The other line goes to the power amplifier and the other goes to an ADC input of the microcontroller so I can sample the signal and then use that data to do some visualizations.

Right photo: left corner of the board has breakout pins from the AVR, on the bottom is the 7-12V input and next to it the signal input. Close to the power amp board are two variable resistors to adjust the gain of the two lines and on the top is the preamplified output that is connected to the input of the power amp. On the center of the board are the pins for a volume adjust potentiometer.

Schematics:
http://akikorhonen.org/varasto/blaster/blaster_control_20100410_1_sch.png

PCB layout:
http://akikorhonen.org/varasto/blaster/blaster_control_20100410_1_brd.png
The preamplifier and...
I bought a "barebone" MP3 player from eBay (search for "MP3 WMA hardware decoder") that has an SD card slot and an USB connector for USB memory sticks. It also came with a remote control.

Almost two months ago I built a small temporary (until I get a better driver and figure out all the details for the enclosure) blaster from an old studio monitor that has been lying around for few years.

The miniblaster is powered with a TA2024 2x15W amplifier (http://allthemods.com/userinfo.php?userid=10&id=6727) and 10x AA cells.

The self made PCB has a small preamplifier that amplifies the signal for two purposes: for the power amplifier and the other signal line goes to a microcontroller that I'll use in the final blaster for some visualization etc. More info about it here:
http://allthemods.com/userinfo.php?userid=10&id=7020

The electronics and batteries are going back inside the case, this is just a test setup as I was testing out the MP3 player.
I bought a "bar...
2x15W TA2024 amplifier arrived in the mail finally. It'll be the amp for my upcoming blaster project. I'm not sure yet what speaker I'll use, but one option is 4" Tandband so the size of the blaster should stay small.

I will most likely power it with 10xAA cells and I might test out some step-up DC-DC converters to power the whole thing from only 4xAA cells. I'll have to run some test whether it's a good idea or not.
2x15W TA2024 amplifi...

Title: Cooler for 6600GT
Created: 18.11.2007 23:21

New cooler for 6600GT (part 2/2)

Few weeks ago I bought a 6600GT for myself and tested it with 3DMark03. After few tests the computer froze up completely. I thought that maybe it overheated and after booting the computer I started Portal in window mode and put SpeedFan next to it to draw a temperature graph of the GPU. After few minutes it was about 80 C. Not good at all.

So I underclocked it from 500/900 to about 400/800 to avoid overheating and crashing and started looking for a suitable cooler and got a good one from Jipa (thanks) few days ago. After some cutting and drilling it was ready and I mounted it to the card.

Results (3DMark03):

Asus A7N8X-X, AMD Athlon 2500+ (1836MHz), 512MB (333MHz), Leadtek 6600GT 128MB

Stock cooler, default speed (500/900)
Load: 82-90 C
Idle: 50 C
Marks: Did not finish due to a crash caused by overheating.

New cooler, default speed (500/900)
Load: 57 C max
Idle: 36 C max
Marks: 7156
New cooler for 6600G...
New cooler for 6600GT (part 1/2)

Few weeks ago I bought a 6600GT for myself and tested it with 3DMark03. After few tests the computer froze up completely. I thought that maybe it overheated and after booting the computer I started Portal in window mode and put SpeedFan next to it to draw a temperature graph of the GPU. After few minutes it was about 80 C. Not good at all.

So I underclocked it from 500/900 to about 400/800 to avoid overheating and crashing and started looking for a suitable cooler and got a good one from Jipa (thanks) few days ago. After some cutting and drilling it was ready and I mounted it to the card.

Results (3DMark03):

Asus A7N8X-X, AMD Athlon 2500+ (1836MHz), 512MB (333MHz), Leadtek 6600GT 128MB

Stock cooler, default speed (500/900)
Load: 82-90 C
Idle: 50 C
Marks: Did not finish due to a crash caused by overheating.

New cooler, default speed (500/900)
Load: 57 C max
Idle: 36 C max
Marks: 7156
New cooler for 6600G...

Title: NSLU2
Created: 23.09.2007 21:48
Making a custom case for a Linksys Network Storage Link.
Front and back plates are ready for some drilling. I had to cut the aluminum from a wide |____| shaped aluminum piece because it was the only piece that had the thickness I wanted. The black plate on the bottom left photo is the original plate from the case. I didn't use the original ones because they had holes in bad places and the material is something very strong and heavy compared to aluminum.
Front and back plate...
New case for the NSLU2 project.
Updated the project page.
New case for the NSL...
New plan for the NSLU2 box. The case this time is the case of a car inverter (12VDC->230VAC). It has a bit more room than the old one. The two first are made with SketchUp and the third is a photoshopped image of the real thing.
New plan for the NSL...

Title: DIY video projector
Created: 23.12.2006 00:41
DIY projector made from a 15" TFT and an old OHP. So far the project has cost 0 :)
The DIY projector in use. The projected picture is about 78" (~200cm) diagonal.
The DIY projector in...
My DIY projector at the moment. I used a 15" TFT (1024x768) and an old OHP. So far the project has cost about 0 because I got the screen and the OHP for free. The TFT panel is cooled with two 8cm fans (the little pieces of tape and paper are just for testing the cooling until I cut the missing pieces for it).

I noticed that the OHP is almost completely same as the one willek used in his DIY projector, only the front panel is different. The lamp is a 24V/250W halogen.

The projector isn't fully finished yet because I'll paint the used plywood and other parts black and cut some light masks, maybe from a thick black fabric.
My DIY projector at ...

Title: Flash cord
Created: 10.10.2006 15:04
DIY flash cord

Title: Old case
Created: 10.10.2006 15:03
Old case project, now collecting dust.
The window for the side panel is made of a magnifying fresnel lens taken from an overhead projector. A bit more interesting than just a piece of plexy glass.
The window for the s...
Finished case. The borders of the frontpanel are lighter because I used plexy glass for the sides. I'll be making a new not-so-fancy case soon, because this case is a bit too unpractical. To change a card (graphics card, sound card etc) I have to remove the PSU out from the way etc. The next case will be bigger and I'll desing the cooling so it will be efficient and quiet.
Finished case. The b...
A SketchUp plan of my case project.
A SketchUp plan of m...

Title: Robot
Created: 10.10.2006 15:03
Robot project
Robot got updated. Now it has a aluminum body instead of plywood, new motors (360 degree hacked standard servos and also the circuit boards are stripped off to allow direct control with a H-bridge), new tires and a wireless webcam (unfortunately not my own, just for testing).

The "brain" is the same old ATmega8 -board as it was in the old robot, also the bump and IR proximity sensors are the same. I attached a wireless keyboard+mouse receiver to control the robot with a keyboard (the operating range with this set is quite small, but it is still quite funny to control it with a keyboard). Don't mind about the big pile of wrapped wire coming from the receiver, because it is for testing purposes at the moment (I'm looking for another set of wireless keyboard+receiver so I can modify the receiver to have a better antenna and a shorter cable between the receiver and microcontroller).

At the moment it has two 9V batteries (one for the camera and the other is for the 5V regulator for the electronics) and four rechargeable AA cells for the motors.

EDIT: And it can wander around autonomously and avoid obstacles (well, atleast most of them)
Robot got updated. N...
Robot got updated. Now it has a aluminum body instead of plywood, new motors (360 degree hacked standard servos and also the circuit boards are stripped off to allow direct control with a H-bridge), new tires and a wireless webcam (unfortunately not my own, just for testing).

The "brain" is the same old ATmega8 -board as it was in the old robot, also the bump and IR proximity sensors are the same. I attached a wireless keyboard+mouse receiver to control the robot with a keyboard (the operating range with this set is quite small, but it is still quite funny to control it with a keyboard). Don't mind about the big pile of wrapped wire coming from the receiver, because it is for testing purposes at the moment (I'm looking for another set of wireless keyboard+receiver so I can modify the receiver to have a better antenna and a shorter cable between the receiver and microcontroller).

At the moment it has two 9V batteries (one for the camera and the other is for the 5V regulator for the electronics) and four rechargeable AA cells for the motors.

EDIT: And it can wander around autonomously and avoid obstacles (well, atleast most of them)
Robot got updated. N...
Back view of the robot project. Here you can see the 4xAA cells with the battery holder and the follower wheel. The small follower wheel is cut and bent from a piece of plastic and then I attached it to a small bearing (same kind as used in normal computer fans). Thanks to the bearing the wheel follows and turns very easily and doesn't affect driving and turning at all.
Back view of the rob...
My robot project. So far it only has two separate collision detectors but I'm working on IR proximity sensors to avoid collisions. That unconnected 6-wire cord in the ATmega board is the programming cable that I forgot to take away. :)
* Body: plywood (I'll make a new body as soon as I find a better material, but for now the plywood is good enough for this kind of prototyping), diameter of the plywood disc is 12cm and the overall height of the robot is about 10cm
* Brain: Atmel ATmega8 AVR microcontroller (32 pin TQFP one with a self made pcb) with a 4MHz crystal
* Programming language: C
* Motor controller: SN754410 (1 Amp Quadruple H-Bridge), you can see the corner of the control board on the front, below the top part
* Motors: two small (2cm long, 2cm diameter) gear motors I got from a friend, no idea where they have been used before but the robot runs nicely with the Lego wheels attached straight to the motors (about 12cm per second so no new land speed records yet)
* Power: 4xAA cells for the motors and 9V battery for other electronics
My robot project. So...