7 segment LED display kit

with this kit is it possible to add 2 more seperate counters with the push buttons?
I am trying to put together a counter like this that I can count 3 sperate items with 3 seperate displays and push buttons.

In order to do this you would need to use 3 separate kits.

regarding the above Kit, is it possible that you have a circuit board that can accommodate two 7 segment displays? I am looking to build a board but only need the numbers to go up to 12, and then back to zero after that, if possible.

Thanks

The up down binary coded decimal IC (4510B) has a pin for carry out (pin 7) and a carry in pin (pin 5). This means that it is possible to use one chip to drive a second chip and it would therefore be possible to get one chip to count to 9 and on roll over trigger the second chip to go from 0 to 1. The only problem is that as this project kit has not been designed to use the carry in pin and as a result it has been set to a state where it is ignored. It is possible to use some logic gates to work out that the number 12 (BCD 10010) has been reached and that a master reset or parallel load of zero is required.

So whilst it would be possible to do it, it won’t be very straight forward and would need tracks cutting plus extra logic gates and mounting of the 7 segment displays on wires in order for them to be together. You may wish to consider using a PICAXE chip or similar.

Hello

Great kit!!! My question is will this kit work for a seven segement display (home made)

Each segment contains 12 led in parallel (each having it's own resistor) the led is about 20ma with forward voltage of 2.2V .......... if i buy your kit can i power my 7 segment display. by simply replacing you display.

The driver IC on this board is a 4511B (BCD to 7 segment driver) and is capable of driving 25mA on each of the 7 segments. If I read your description correctly you are looking to drive 240mA per segment. So would need to connect a transistor between the IC and the LEDs.

Is it possible to add an extra switch with this kit thats switches down,so you have both.
Aslo is there one with a red display instead of green.

The IC that does the counting has an input to count and an input for direction. If you wanted to have a button for up and a button for down rather than a slide switch for direction and a button to step then you would need some logic. The step input wants to be active if the up or down switch is pressed. In other words feed the up and the down switch (with pull down resistors) in to an OR gate. The up / down pin should be connected to the up button. This now leaves the minor issue of propagation delays and set-up times. At 5V the up / down signal needs to have been present for 300nS before the clock signal arrives. In hardware this means connecting a resistor followed by a capacitor to 0V and then using the point where the resistor and capacitor connect to feed in to the clock in. If you use a 1K and a 1nF it should give you the required delay.