MK133 more power question

I recently bought two of the MK133 quiz table kits, and have a question:

What modifications would it take to power this board from a 12V source instead of a 9V battery? Also, in so doing, what would be the new power restrictions for an external indicator? Another question, is there a modification which could be made to increase the current draw maximum of this external indicator?

There are many intriguing devices out there which run at 12V and I’m inclined to build a kit to make use of one. I am electronics savvy enough to make modifications, but just don’t have the time to try to analyze the entire circuit. Thank you in advance.


I’m sure you’ll understand that we do not have the time to develop modifications on demand :slight_smile:

The circuit will work on 12VDC without modification, however, the output current cannot be increased as-is. If you need higher output currents, you will have to connect e.g. a relay to the outputs.

I’m trying to connect Relays to each to control 120VAC lights. the MK133 works as designed while on 9V battery.

My problem really is that the 9v battery alone will trip the relay, but when connected to the lightbulb output they do not. I see 9.6 VDC from the battery, and 8.4VDC from the Lightbulb output.

I connected my mk133 to 12vdc as per the suggestion here because i need more voltage through to lightbulb output. The board works almost correctly. The pressed LED and correct LED light when holding an answer button. None of them stay lit and wait for the quiz master button.
[color=#FF0000]HELP! i need this working tomorrow![/color]

thanks in advance for any suggestion.

Hi Here in Cape Town I am about to use the velleman mk133 quiz kit for an inter school challenge. Is there anyone out there who can tell me what relays to use and how to connect them if I want to use another 12v power source and stronger led lights thanks johan