Sunday, November 19, 2017

TomTom Runner Cardio GPS Watch, Repair Start Switch

TomTom Runner Cardio start switch is not responding. The video below is showing how to repair start switch. A small piece of paper or plastic is inserted to allow rocker to press micro switch.

Sunday, August 20, 2017

Aluminum Laser Pistol For Dry Fire Practice

This laser pistol can be used to shooting practice safely at almost anywhere: at home, at the office, etc. This laser pistol also can be used as a laser pointer for presentation.

Pistol Laser Aluminium Untuk Latihan Menembak Tanpa Peluru
Pistol laser ini bisa digunakan untuk latihan menembak dengan aman di mana saja: di rumah, di kantor, dll. Pistol laser ini juga bisa digunakan sebagai laser pointer untuk presentasi.

3 targets shooting video

Wednesday, July 19, 2017


This book is a complete guide to build a beautiful model of submarine that can dive, surface, and move forward without electric power. The submarine design is very simple, yet effective. Nothing complicated moving parts inside the submarine. The submarine is very easy to be crafted by using cheap household materials and can be done by 10 years old kid.
The basic principles that support the submarine performance is state of the art technology. Therefore, this book is a good education for kids or adults who would like to learn about submarine technology.
Some boat designs are tested to find the best performance. This way readers can analyze, compare and hopefully find and create their own design, which could be even better.
This submarine science toy is using baking powder as ‘fuel’. Using origami of plastic paper and polystyrene, this submarine looks like a real submarine.

View a video about a submarine in action.

More info please read in: Home Made Working Model Submarine

If the link doesn't work, copy-paste below address into your browser:

Monday, May 22, 2017

How To Make Science Toys Ship & Submarine: Made Of Household Materials, Battery Powered

This book is a complete guide to build model boat and submarine with electric power, and made of household material such as: polystyrene, drinking straw, rubber band, zinc plate, etc..
Boat and submarine are an application of Archimedes’ principle. This book guides reader to build science toys to learn and practice Archimedes’ principle.
Beside Archimedes’ principle, hydrodynamic (the study of liquids in motion) also become a major consideration to ensure boat and submarine to perform well. Hydrodynamic not only determines boat and submarine body design, it determines also propeller design.
By understanding about Archimedes’ principle and hydrodynamic, the submarine can be set to dive, hover in water, and resurface.
Check to below address to watch videos about homemade drinking straw submarine in action:

More info please read in the book:


If the link doesnt work, copy-paste below address to your browser:

Thursday, April 20, 2017

Electronic Chime Sound Target For Laser Pistol

This shooting target are used for shooting practice with laser pistol. The laser gun is made of a modified laser pointer with a pistol handle and a pulse-shaped laser beam that resembles a bullet passing through.

This shooting target is made of a stainless steel cup. There is a hole in the center of the target paper, if the laser beam hits the center (bulls eye), then the laser beam enters the cup, and will be reflected. Since the target paper is smaller than the cup's mouth, the reflected laser beam can be seen as a luminous outer ring.

See the following video:

An electronic circuit can be applied to this shooting target to create chime sound like bell or like steel hit by a bullet when bullseye. See the following video:

Monday, March 20, 2017

Sasaran Elektronik Berbunyi Denting Untuk Pistol Laser

Sasaran tembak ini digunakan untuk latihan menembak dengan pistol laser. Pistol laser tersebut dibuat dari laser pointer yang dimodifikasi dengan gagang pistol dan sinar lasernya berbentuk pulsa sehingga mirip peluru melintas.

Sasaran terbuat dari mangkok stainless steel. Pada bagian tengah kertas sasaran terdapat lubang, jika sinar laser tepat kena bagian tengah (bullseye) maka sinar laser masuk ke dalam mangkok dan terpantul. Karena kertas sasaran lebih kecil dari mulut mangkok, maka sinar laser yang terpantul dapat terlihat sebagai lingkaran luar yang bercahaya. Lihat video berikut:

Sasaran tersebut dapat ditambahkan rangkaian elektronik agar berdenting seperti lonceng atau seperti baja yang terhantam peluru jika bullseye. Lihat video berikut:

Monday, February 20, 2017

Bicycles At Fatahillah Square, Jakarta Old City

Rental bicycles at Fatahillah square, Jakarta Old town. Some classic buildings were built by Dutch. Best time to visit in the afternoon. Cafes and restaurants are available here, good place for gathering. Easy to access by train and bus as it is close to commuter train station and busway terminal.

Penyewaan sepeda di lapangan Fatahillah, kota tua Jakarta. Beberapa bangunan klasik yang dibangun oleh Belanda. Waktu terbaik untuk mengunjungi di sore hari. Cafe dan restoran tersedia di sini, tempat yang baik untuk pertemuan. Mudah diakses dengan kereta api dan bus karena dekat dengan stasiun kereta api komuter dan terminal busway.

Friday, January 20, 2017

Laser Pointer Pistol With Optical Target

Laser pointer  in the photo above has a wooden handle as hand grip and becomes a laser gun. Laser is activated by pulling the trigger. There is a circuit that use a condenser in order to turn on the laser for less than 1/4 seconds. The laser pulse is like a bullet flying to target, watch below video.

By using a simple switch, the laser can be set to turn on continuously, and can be used as a pointer, such as for presentation at the office.

The shooting target is shown below. The target will deflect the laser beam and project the beam as a line on to a wall or screen at the back of that shooting target. So it can be noticed if the target hit by the laser beam. If laser beam doesn't hit the target, then the laser beam will be seen forming a bright small point on the wall at the back of shooting target.

In the following video. shooting target will project laser beam on to the wall and form star-shaped if the target hit right in the center (bullseye).

If the target hit on it's side, the laser beam will be projected on to the wall and form a line. The following video shows the laser beam of pointer hit every sections of target.

Because the laser beam can still be switched on continuously, so this laser pistol still can be used as a pointer for presentations.