The flashtube is probably bad
I wound some extra coils of wire around the original flashtube and still was not able to get good ignition.
I did have an old Rollei E36RE flash with a bum/shorted capacitor. I took the tube out of this unit and jumped it to the back of the tube socket on the EG&G and it works perfectly. Fires every time!!
This tells me the flashtube that came with the device is worn out.
One remaining problem is that the flash intensity on the settings 10-2 and 10-3 is almost exactly the same. 10-4 is much less intense to the eye and is probably working correctly.
Radio Shack Flash Tube Makes Good Replacement
I wound up just going to Radio Shack and I got the Flash Tube replacement they sell. I re-soldered this to the base that the original flash tube was connected to. Making shure to get the polarity correct. The Radio Shack tube has a little red dot on it. This flashtube cost less than $10 USD. Now my unit fires perfectly.
Comparison of Wejex and EG&G
Eventually I would like to compile all this info into a buyers guide. But for now I will just post some things as I think of them.
Wejex-incandecent small bulb running off of about 5 - 10 VAC
EG&G-xenon flash tube
Wejex-one second, controlled by a shutter driven by a clockwork motor.
EG&G-1/100, 1/1000, 1/10000, controlled by fixed capacitor size and fixed resistors.
Wejex-sturdy metal, but spring loaded so need 3 hands to load film. Opens TOWARD the operator.
EG&G-flimsy plastic, connected to trigger so chance of premature firing. Opens AWAY from the operator. Stays open for loading.
Place to put filters:
Method of adjusting exposure:
Wejex-variable resistor for light intensity
EG&G-3 choices of exposure duration. Intensity must be controled with ND filters
Wejex-simple transformer, runs from alternating current.
EG&G-complex 700volt filtered and regulated AC power supply with a rectifier circut. Unfiltered DC output (no filter capacitors to replace or to blow up)
Wejex-now made by Tobias; still in buisness, though support for the older white light models may be NA.
EG&G- still in buisness(?), though support for the, no longer made sensitometer may be NA.
Shop manual or owners manual on the internet:
Wejex- built in
What I like best:
Wejex- I like the fact that it is so simple. It can be copied or rebuilt from simple components (older white light model). Newer models may be more complicated.
EG&G- Excellent workmanship and circuit layout. More complex than the Wejex, but still primitive enough to be fun to work on.
What I don't like:
Wejex- little light bulb may be too yellow even with 80A filter in place. Color temp probably changes with lamp voltage. Though, these factors probably don't matter much in real life film testing for gamma.
EG&G- some components are specific to this unit and are probably unobtainable (like the monster super-fast discharge capacitor). Suitable replacements ARE available, but may alter the function of the unit. Though, who really needs exposures of 1/10,000 sec in fine art photography. Those fast speeds were for matching film sensitivity data to high-speed xenon flash subject matter.
Why you need a sensitometer
The need for a sensitometer is similar to the need for an exposure meter. One does not really NEED it but it can help out. With experience its use becomes less important, but when faced with the unnusual or out of the ordinary, it is a neccessity.
People learned photography years ago with instruction on how to use a light meter. Sensitometers were not deemed neccessary (in my opinion) simply because they were so EXPENSIVE. A current unit from Agfa cost $24,000. They are so expensive because they can be calibrated for ISO standard determination. Unless one is running an ISO standards laboratory, this is unneccessary.
THE MAIN REASON THE FINE ART PHOTOGRAPHER NEEDS A SENSITOMETER IS TO DETERMINE A STARTING POINT FOR DEVELOPMENT TIME.
If you use the same film and developer combination all the time you DON'T need a sensitometer. Likewise if you shoot in bright sun all the time you DON'T need a light meter. I was like this for many years, however, the film and developer that I like may soon be extinct.
UNKNOWN FILM/DEVELOPER COMBINATIONS ARE THE MAIN INDICATION FOR SENSITOMETER USE
For generations one had to guess at a starting point based on mfgs tables or the experience of others or trial and error.
Use of a sensitometer (and densitometer) puts some order into the process and allows one to zero in on a development time by comparing the slope of the new film with the slope of a known good film/developer combination.