Powering Namco Joystick, 4 LCD, and Audio Amp Together With 6V Adapter—Is It Safe?

I'm building a small desktop video arcade system using one of those old Namco Joystick boxes which are battery driven (4 AA batteries) and have an audio and video RCA jack which you hook up directly to a tv.

There are 3 main components.

*Video Game/joystick box*
http://bit.ly/1lpVuXr

Regarding the power requirements. All I know is that it takes 4 AA batteries. So 6 volts. I don't know how much current it draws. Can I use a multimeter to measure this? Do I need this information to move forward?


*4 Inch LCD Video Screen*
http://amzn.to/1lUq0Kj

Here is the range of power options for this device.
Voltage/Current/Power
5.1v / .27a / 1.377w [lowest stable voltage]
6.0v / .25a / 1.5w
6.6v / .23a / 1.518w
7.4v / .20a / 1.48w
8.0v / .18a / 1.44w
8.6v / .17a / 1.462w
9.2v / .16a / 1.472w
9.8v / .15a / 1.47w
10.4v / .14a / 1.456w
11.0v / .13a / 1.43w
11.6v / .12a / 1.392w
12.0v / .12a / 1.44w [highest recommended voltage]

*Small Audio Amplifier Board* to drive a small speaker. Probably not more that 1 watt I'm guessing would be loud enough.
Not sure what to use here. Any ideas? If this also can take 6 volts then everything can be powered by one 6 volt power supply. I'm thinking of this as a possibility.
https://www.sparkfun.com/products/11044


I've already built one of these small desktop video arcade machines (see link below) but ended up using both the video game batteries (which powered the video game) and a separate 12 volt power supply (which powered both the LCD and an audio amp board) and I didn't like that as you had to replace the batteries as well as have it plugged in all the time. I ended up using a small 3 watt amplifier which was WAY to powerful. I could only turn it up a little before the volume was earth shattering. And this was a small audio amplifier board. I would prefer it to be as simply as possible. Just need to amplify the RCA audio output to levels appropriate to playing on a kitchen table. Not very loud.

Ideally I would like to:

Power all three things with the (4 AA batteries) that comes with the joystick. That would be ideal as it would allow this small video arcade machine to be portable. Assuming though that the batteries didn't drain way too fast.

If the batteries don't provide enough current then the next best thing would be a power adaptor. Something like this assuming that it could power all three components (video game/joystick, video screen and audio amplifier).
http://amzn.to/1rza3bG

Once I have the parts worked out I'm going to teach a DIY class to 5-10 young under-privileged kids where they can put their own arcade machine together. I'm hoping to keep the costs down to under $50 as I will have be self-funding this.

So my issues are:
* Can I power all this with one power supply?

* Can you recommend a small audio amplifier. Preferably less than $8 or so. I'm trying to keep the parts under $50.

* And are there issues like voltage spiking that I have to worry about when connecting multiple components like this to one power supply? Or can I just hook them up in parallel assuming they all take 6 volts and the total current draw is less than the power adapter is rated?


Any help you could give me would be greatly appreciated.

Here's my first attempt from last year.
http://www.jochumson.com/project7.html

Hi Chris,

You have a very nice project.

6V 1A power supply would just be enough to power those three devices but you could not maximize its features.

Assuming the 4 inch video screen eats up more or less 300mA, video game around 200mA and audio amp + speaker around 300mA.

For 6V 1A supply, obviously it is enough but you will be having problem when you increase the volume since it requires a lot of force(assuming that voltage rating is a force) to drive the speaker to a higher level of sound. You may use capacitors to reduce the work of supplies but this will requires a lot of test.

You may use 12V 1.5A Power Supply to make it simple and you will save a lot of time
something like this -> http://tinyurl.com/psqnhxr

There is just a slight price difference between the 6V 1A power adapter or you can find lower price than that.

I hope it helps.

God Bless and Good Luck.

Best,
Neil

Neil- Thanks very much for you helpful comments. Regarding the 12V 1.5A supply. Since my components require 6 volts should I instead use a 6 Volt 1.5A supply like this one?
http://amzn.to/1pCXScN

Any thoughts on voltage spikes causing a problem. I read somewhere in an Amazon review for one of these LCD screens that they produced a voltage spike when powering on. So I'm just wondering if I need to provide any isolation across components to keep one from frying the other. Any thoughts on that?

Thanks very much!

Chris

Hi Chris,

6V-12V 1.5A supply that would be fine since it is available.

for spikes you can use some capacitors , diodes or even resistors that depends on your circuitry.

or try one of the clipping circuits - > http://www.circuitstoday.com/wp-content/uploads/2009/10/Different-Clipping-Circuits.jpg



Best,
Neil