I bought the wood box on the rear side at Tokyu Hands for only 157yen.($1.50) I intended to make a hole at bottom, face two boxes face to face and make a complete box. But my NC machie's work area is too small on Z axis to handle this box. So I changed my plan to make a buffle by acrylic plate. My machine can easily handle 5mm thick plate. :-) Because the speaker unit is too thick to put in the box, I should groove the buffle in order to offset the unit to the front side for 4mm.
However small it is, it generates very good sound. As it is very small, it is nearly a point sound generator that makes excellent sound image localization. The speaker unit is good enough to generate big and clear sound. Bass component is not good as bigger woofer units, but great to listen to music on desktop. I often get into listening to music and stop my task. (^^;
The "Synthesizer" is a intractive design prototype while I joined to build. As there was an illegal copy of movie was on You tube, this time is a formal release of the product and introduced on SONY's web site.
My name is not on the list, but actually I made most of the system. USB interface board design (Circuit design and PCB pattern design, and USB firmware. Movie display appliction software on the Power Mac G5 below and movie data itself(3 types out of 5).
I like this one, and would like to offer some chance to all of you to touch and control it, but it's just a prototype, and exibition showing them is very limited. Sorry.
LA4902 is a non linear audio power amplifier chip that is very efficient and have good performance in sound. I bought it in Akizuki-denshi at Akihabara sometime ago, it was 300 yen for two. Pretty cheap huh. :-)
As this chip is in a shrink DIP package(70mil pitch), I had to make a PCB. As always, I made traces by EAGLE and never etches but cut copper by EGX-300.
You can see many traces on the back side made by cutting machine. On this side, there are some SMT devices. 3pin small outline chip is a shotkey diode. As this one has very small pin and very small itself, soldering is very difficult. Moreover, ground plane is very near beside a trace and has no resist mask on it. This can easily short the circuit and make it veeeeery difficult to solder.
The reason why I made a "Monaural Amp" is I wanted to drive a Base amplifier that I bought for only 1000yen as a JUNK. This one had good working speaker but all control variable resistors have noise and used with DC/AC inverter as outdoor use, it amplifies buzz from the inverter.
The reborn amplifier has no tone control, so those controlers are removed and sealed by screws.Headphone jack is now a DC jack.
These effort made a Good sound DC powered base amplifier that can be used with lead-acid battery outdoor. Output is powerful enough to hear from not very far places. This IC can be driven up to 18V and that probably makes it louder. Now I hear indoor with very small 12V 1A AC/DC adaptor. As there's enough margin to insall battery inside it, it is a good idea to make it completely portable by itself.
Anyway, I made it for under 2000yen with all those qualities. It's a very great price.
As I wrote before, I should write an English version when I write my Japanese Blog entry.
I don't know if there's any access to my Blog or not, but I left my log unattended for so long time.
As I didn't write blogs, but I didn't stop making something. I tried making IR activated stopwatch for inline skating that doesn't need wires between start and goal, and very big LED number display for those stopwatch. That one also connects the stopwatch wirelessly. Unless, there should be some wire around skating ground and that's too dangerous.
Today, I made up a starting signal for inline skate slalom racing.
It's a little bit hard to see though, there's also a smal beeper on the bottom right edge. This makes signaling sounds as booooo!, silence, boo!. boo!, peeee!!
These LED modules are originally for environment light data communications and as so these make very strong light. It blinds me if I see the lights straight before it.
Starter can activate the signal tower wirelessly by a small keychain commander.
On the right side, black connector is a DC plug/jack that supplies 12V DC, and green one is a 3.5mm stereo audio plug/jack that connects racer's start detector in order to check flying start.
The green boad on top is a wireless receiver that recieves commander's signal.
Starter can warn some violation manually as quick blinking and sound. It automatically detects flying start and it also warns like that.
This one may debut on Hikarigaoka inline skate festival next Sunday.(Oct 21st, 2007) I hope it will foster their tension on their mark.
As I wrote on the previous article, VOX has problem wih writing in Japanese when I use Safari.
すっかり別のBlogに根城を移してしまってますが、久々に戻ってきて思い出しました。そうだSafariに対応してなかったんでした。
CQ誌になんだかソフトウェア・ラジオ実験基板が付いているというので、つい買ってしまいました。
が、あの厚みからして当たり前なんですけど、部品がな〜んも載ってない。(^^;
この程度ならうちで切削で作った方が良いじゃん。金メッキ端子はともあれ、手持ちの部品に合わせられるし、もっと表面実装品も使えるので小さく出来そう。これならPRoCネタが載ってるトラ技の方を買ってくるんだった〜。ま、基板がついているという言葉に嘘偽りは全くないんですけどねぇ。ついトラ技のマイコンボードみたいなイメージを思い浮かべちゃったんですよねぇ。買った本屋がご丁寧なことにヒモで結んで開けないようにしてあるもんだから、付録の薄さを確認することができなかったのも冷静さを欠かせることになった原因かなぁ。
PRoCってのは、ワンチップでWireless USBが構成出来ちゃう石なんですよねぇ。これは面白そう。CYWUSB6953がDigiKeyで$9.13。ちょっと悩ましい値段だな。半分くらいだと良いなぁ。ま、62.5kbpsとか1Mbpsってことは、Certified Wireless USBじゃないってことですよね。nRF24E1とどっちが良いかと言われると微妙かもなぁ。
ということで、修正したバージョンです。LEDが付いて、ちょっと端子が減っとります。
さて、「日々是自作」とサブタイトルをつけた通り、本来ここには作ったものを公開する場とすべく登録したのです。別にアニサキスの話や、Browser対応へのグチはあくまでも試し書きに過ぎません。
ってことで、本題の今日の基板。なんかそのうちに雑誌に投稿されるそうなので、詳しくは書かない方が良さげですが、高校の先輩からの依頼で作った基板です。
ハトメラグで入出力とか言われて、使ったこともないのでちと戸惑いましたが、別にフォトカプラで絶縁した入力に従って、適当な出力をシリアルに出してやるだけのものなので、マイコン１個で簡単に済む話です。ちなみに、まだソケットに刺してませんけど、マイコンはAT90S2313のつもりです。
いつも通り、9月に買ったEGX-300を使って切削で基板作成。今回は片面で十分なので、片面基板を使いました。でも、秋月の両面生基板が激安なので、実はこっちの方が高くつくんですよねぇ。(^^;
フォトカプラには、こないだ秋月に行ったら置いてあった表面実装品を使って見ました。やっぱ小さくて良いですね。TLP281という東芝の物みたいです。
が、なんと今になって設計変更の依頼が入ってしまったので、これはボツ基板になりそうです。
まぁ、入力不可能と言うわけでも無いけど、ちょっとキーインを間違えるとウザイので、仰せの通りFirefoxを使って見ることにする。ま、WindowsマシンではFirefoxを使っているので、さほど違和感があるわけでも無いんだけどねぇ。
たしかに、入力している最中に「あ゛〜〜〜」ってことがないので、こっちの方が快適ではあるなぁ。
でも、やっぱりデフォルトブラウザはSafariのままなので、早く対応がとれると良いなぁ〜。
on Very small speaker box