Hello,
I am a new member and I own a Mata Hari. I have a few lights out and the bulbs are fine. Do i have to sauder or use fine sandpaper to fix the problem?

If someone could give me some advice that would be great.

Where are you located, maybe somebody local can get you pointed in the right direction...

If not - try this:

http://www.pinrepair.com/bally/index.htm

If the lights are general illumination it's probably the pins or connector on the power supply/rectifier board, if it's a feature lamp, chances are it's a transistor on the lamp driver board.... it'll show you in your service manual which transistor is for which lamp.

Welcome to MAACA !

You need to identify if the bulbs that are out are part of either:
- General illumination (GI), should be always on, or
- Controlled lamps.

The first place to check are bad lamp sockets for both categories.

If a GI lamp, there is not much to them except wiring and socket.

If a controlled lamp and you are certain that the wiring, socket and bulb are OK,
then the issue is either with:
- lamp driver cold solder joint under header pins, and/or
- bad 0.100 pins on the connector(s) of the lamp driver, and/or
- bad SCR on the lamp driver controlling that lamp (you will need a schematic
   to cross-reference the bulb out with the SCR)

Good luck & Cheers,
- Sylvain.

One of the first things I ever made to help me fix machines was just a lamp socket with a couple of wires soldered to it with alligator clips on the end.  This allowed me to clamp onto the 6 volt bare wire and onto the socket of the burned out lamp to check whether it was a bad socket or not.  If my test lamp lit up, I new it was the socket.  If it didn't, I knew it was something else.  With feature lamps, if the sockets are good, the problem 95% of the time is a burned out rectifier  ( a.k.a. transistor ) on the lamp board.  

Ballyboy has steered you in the right direction.  Clay's guide is the bible when it comes to troubleshooting these things.  If you have specific questions for that machine, I have one so may be able to help you out.

Does your machine have circuit boards in the head board or a bunch of things that go "click click", and is your real name Keith ? If yes to the first or both questions, don't answer any questions on this forum, it is simply for your own good.

Just send me a PM and we'll get your machine fixed.

(Ya never know)