During the DvdRA, we received from Hans Boonstra, a satisfied customer, the schedule of an auto power on / off circuit for the bat detector. If you add this, the bat detector automatically switches when you connect a headset.

We were equally excited about how the extension of the Morse Phone would be, but here it is.

It eventually became a circuit board mounted underneath the Morse Phone.You will have a full mobile signal device


Addendum The Morse Phone

Now that a large number of Morse Phones have been sent, we have also received some feedback from our customers and we would like to share them with you

It concerns: thePiezo speakertje,Coil,Tip for construction

Every year, the Service Kring JOTA-JOTI developed a building kit for the scouts to solder themselves and then enjoy themselves with the result.

Morse Phone2017 1

For this year, "The Morse Phone" has been developed, as the name suggests, you can start with this kit with Morse code. The Morse Phone is a Morse-buzzer that can be used independently, but can also be linked with other Morse Phones, communicating, after all, is done in pairs! The Morse Phone is inspired by the Fuller phone. For the technicians, an article on this subject can be found elsewhere on this website. Google also gives a nice explanation of the origin and use of the Fuller phone.

The kit comes with all the components except the 9Volt battery.



In all these experiments make use of the contacts between the blades of the Light Mill. It's easy when you attach a piece of flexible electrical wire here. Stick a piece of tape over the light sensor.



Color  the patches starts and  finish with a soft black pencil (preferably 6B). Slide the metal surfaces
paperclip on the  surfaces, connect the wires to the paper clips. Draw a path through the islands and bridges. If the path is well marked, without interruptions, the mill will run faster.





LM7Lost your wire???
In a pile of wire ends it is sometimes difficult to find the acompanied ends. Try it with the LightMill!





Pak both the end of a wire of the Light Mill bite. Join hands, watching a good look at what happened!



Which materials conduct electricity? Try it with the Light Mill!


Connect different resistances between the wires. What can you say about the speed of the mill and the value of the resistor?


This is a guide on how to build a simple enclosure for your bat-detector or for your bat-beacon. The enclosure is based on 50mm PVC-tubing and PVC-caps.You can also download the document



Digi-Dice 2014

This year, the Service Kring JOTA-JOTI again managed to establish a fun and educational construction project what we called Digi-Dice. As in previous years, this kit is intended for use by children soldered together (under supervision) and to become familiar with electronics. Besides this is a nice kit it is also useful because it can be used in Scouting games on various ways

Digidice2014 Kl1


Usage and options:


Once the batteries are installed, the Dig-Dice and performs a self-test.

All segments go on one by one and then burn all segments simultaneously. The Digi-Dice is now ready for use as dice. Press the button to start the dice, a running light appears and a number is displayed. Press the button to throw again.

However, the Digi-Dice has even more possibilities. By holding the button down longer, you can switch to another mode, this is indicated in the display.

There is the d. of dice, as we have seen above, we can note the dice here and there will be a number from 1/6 to appear on the display. One press of the button is throwing again.

   Then there is the r. of random (random) in this position, the Dig-Dice will provide a random number from 0 / to 9.

  Then there is the G. guide (guide), in this mode you can use the Digi-Dice for a direction to determine this, go back completely random There are three possibilities, turn left, turn right and go straight.

Finally we have the F. flash (flash), this is a kind of running light, the display will continuously run in circles.

Except that the Digi-Dice a fun and decorative structure there are also countless fun games to play with. Using a number of printing a fun scavenger hunt in the neighborhood or in the forest and use it as a die in games.

Do you have other ideas please tell us!

Do you have comments or want to provide feedback on the Digi-Dice?

Do you have comments or questions about the Service Circuit JOTA-JOTI?



pointer3bDo you just hate when you can not find your tent in the dark. Or that the one leading Post-it just is not enough standing out among all other memo leaves? Then you really need the "Pointer"! The Pointer is a a running light that turns itself On in the light or in the dark.

The speed of the running light, in the form of an arrow, is variable. By pointing the Arrow anyone can draw the attention to something important. But you can also take off for a trip in the dark: Hang the pointer on an inconspicuous area. If a flashlight is shone, the Pointer work and you know which way to go (just follow the arrows !).

Of course you can also use the indoor Pointer: Hang it next to your own bedroom door and at night you can always find your own room back! Have you become very enthusiastic of soldering: Three pointers form a perfect circle!

The kit is powered by a 9V battery and will cost around 4.50 Euro go

You can order your Pointers NOW



Lasergame MKII

The laser game MKII is a remake  of last years  Lasergame MKII 2011. The game has the following Features:

- Adjustable team indicator, Team Red, Team Green, Team Red / Green or no indication

- Sensitive to visible light (flashlight)

- Sensitive to infrared (remote control)

- Reset with a magnet, uses a Hall sensor is not a fragile reed-relay!

- Settings only change with simultaneous activation of the select button and magnet

- Fraud proof: the loosening of the coupling, the battery in alarm Lasergame

- Supply with a 9V battery