Tube Clock digital

No Comments »

This clock is made up of four IV-17 alphanumeric VFD tubes. As it ships, the electronics come in two parts – the base with the microcontroller and the shield with the VFD tubes. The base can support up to four sixteen-segment tubes or twenty seven-segment displays.

It ships with an ISP header for easy software upgrades. If you want to make your own four letter word machine or to experiment with VFD tubes, this is a great place to start.
I received this device fully assembled but it normally ships as a kit. Nearing the menu structure is pretty easy and there is a manual online to make setting the device easier.
A FLW modification is in development to support this feature. Overall – I’m a fan of this little device.

[source]

Metal Percussion generator

No Comments »

synthesizer-controlled equivalent sound as produced
tuneable VCOs which supply rectangular output
One of four identical KOV (keyboard output
fast opamp types ensures linear VCO operation well
linearity of the voltage-frequency curve relevant to
The outputs of buffer opamps Ar . . . A4 (ICI, Type
rail grounded. rectangular VCO output signal has a 50% duty factor;
if not, adjust the relevant preset.
As the four VCOs lack a linear to exponential KOV
type. KOV signal whose frequency doubles

RFID Car Finder using PIC12629

No Comments »

The PIC and the ID-12 are powered by a 7805 5v regulator via some basic filtering caps.  The PIC is in an endless loop at this point, reading available data from the ID-12.  Once a card/tag is read, it compares the string with up to 10 tags it has in EEPROM.  If one matches, it activates the transistor which in turn activates the relay and the program stops.  If there is no match, it just keeps waiting for data. The bi-colour LED indicates the status.

source : http://www.instructables.com/id/RFID-Car-immobiliser-with-PIC12629/

Over Voltage Protector Circuit

No Comments »

Here is Simple Over Voltage Protector. This circuit protect your circuit from over voltage. A silicon-controlled rectifier is installed in parallel with the 12-V line and connected to a normally-closed 12-V relay, K1. The SCR’s gate circuit is used to sample the applied voltage. As long as the applied voltage stays below a given value, SCR1 remains off and K1′s contacts remain closed, thereby supplying power to the load. When the source voltage rises above 12 V, sufficient current is applied to the gate of SCR1 to trigger it into conduction. The trigger point of SCR1 is dependent on the setting of R1. Once SCR1 is triggered (activating the relay), K1′s contacts open, halting current flow to the load.

keep looking »