What is wrong with MY unit?
When I first took the unit out of its packing I immediatly noticed "THAT SMELL" of fried components. My initial exploration did not yield any thing that looked burned up, though. The fact that the flash durations did not match the switches was curious, though.
On second exploration, my NOSE and an infrared temperature probe led me to a resistor on the main circut board. The board is labeled "R4" at that position. This looks like a 1/2W resistor. Color code shows Gold (5%) and 150K resistance (15 x 10k). Close inspection does reveal some discoloration, and the infrared temp. gun shows that this thing heats up pretty fast when the power is turned on.
Also, noted was the fact that the flash was not firing all the time. I could see a small 'puff' from the ignitor (when looking at the xenon tube) but the thing would not fire every time.
Here is a quote from (http://mit.edu/6.933/www/Fall2000/ed...dgertonWW2.pdf)
"The trigger switch is initially open, and the trip
capacitor is charged to a voltage Vs. Vs is determined by the voltage divider composed of R1
and R2 and E, the voltage of the power source:
When the switch closes, the energy in C1 is pulsed into the spark coil, and a voltage is applied to
the trigger electrode wrapped externally around the flash lamp. This excites the noble gas in the
tube (typically xenon) and decreases the breakdown voltage of the gas. When the voltage across
capacitor C is greater than the gas' breakdown voltage, the gas in the tube will ionize and create a
brief flash of light."
So, the bum resistor turns out to be on the "10-3" flash circut (the one that seems to be firing TOO bright). I suspect that a derangement in this resistor is also causing a problem with the ignitor capacitor charge voltage.
Anyway, today I need to go to Radio Shack and get a 100K and 47K resistor (thats all they carry) and put them together in place of R4 to see if the unit will work correctly. If so, I'll order a correct 150K from an online source.
I guess this is just another reason not to play the "e-bay game" unless one likes tinkering with stuff.