If you poke around the net, you will find the parts and the service manual. Try looking for "SB-600 parts list" and a similar search for the service manual.
- Usually it is the tube that is shot int he SB-600 after it falls down.
- Nikon's parts department in the US will sell you a new tube (part # XE701) for about $11 + shipping. You need to be adept at soldering to replace it
- a simple test to determine whether the problem is on the tube end is to use a voltmeter to measure the flash capacitor voltage. It should be about 300V DC. Look in the service manual where they show you how to discharge the capacitor- use the same contacts to make the measurement.
- if all else fails, a broken SB-600 goes for $40-90 on Ebay!
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