When the ball goes into lock during video mode, the backbox and the playfield lights go out. I'd like to have a 6v light turn on and illuminate a Davros figurine placed on the back of the playfield. So far, the only thing I can think of is to have a transistor wired as an and/or gate with power linked up so as the playfield lights go out, the transistor switches power to the dedicated light shining on Davros.

I have very minor experience in working with electronics. I know there is a way to do this, I just don't know the engineering principles behind achieving this goal. Is there anyone who would know the proper way to making such a system work? Or... is there a manner or method to making this work within the available electronics on the light board or CPU? Any suggestions would be greatly appreciated. Thanks to all who help!

I read your suggestion and looked up PNP transistors. This sounds exactly like what I need. I also read about setting up the leads from the transistor, but I don't know how I would do this, since my experience is limited to this point. Do you have a schematic to illustrate how I'd go about this? Thanks so much for steering my in the right direction, Zacaj.

A PNP transistor has 3 leads. The query I have regards power to the light when the transistor switches GI power off. If there are only 3 leads and one is the ground and one is the power in, then the last lead would be the send lead to the light which switches on as the GI switches off. In this case, where does power come from in order to turn on the light after the GI is switched off?

That is excellent! I thank you so much for your help. I knew there was some way via transistors but I don't know the theory well enough to understand and utilize the proper options. I'll search for the proper PNP transistor. Thank you again, Zacaj

Yes, the GI is AC, so I believe you're right about the diode. Since you posted the schematic I began looking at different versions used for amplification and there is a diode present as you described. Now I just have to learn if a transistor for my application exists and locate it. I've found many with higher voltages at 500mA. I may have to step the voltage down with a resistor to create the 6 volts I need.

This is all new to me and I'm trying to learn as much as I can through info over the Internet. It's like trying to learn law by walking into a library and seeing 200 volumes of legal history. Where do you start and why, regarding the tons of information each time I do a search on a subject.

I thought about a relay prior to considering a transistor. Having little knowledge of electronic engineering, I'm not certain which is the most efficient way to go. Would you know of such a relay and where I may purchase it? Furthermore, would I need a small PCB on which to mount these components? And if so, how would I go about making or purchasing such a thing, since I've never done this before. Sorry about my ignorance. I'm trying to learn this stuff as quickly as I can without doing something the wrong way.

Thanks for the information, erak. I'm in the process of educating myself with regard to applying the proper solution. Now all I need to do is translate this schematic into a physical device that I can manufacture and use.

I'm really looking forward to making this work. I'm going to use the GI from the back box, since those lights don't flash during attract mode. And using a 12v light will work just as well as a 6v.