The magic smoke escaped.....
So, I'm reasonably sure the replacement driver for my old Laserwave dual 640nm module wasn't supposed to totally cook one of the diodes and the Lasorb! The amount of smoke from a sealed module was fairly impressive!
A few months back, I lost a driver and Laserwave said they could supply me a replacement for reasonable money, so took them up on it. Its been a very busy summer so only just got around to fitting it, ready for a job next weekend, and plugging it in and turning on resulted in immediate magic smoke release!
Having given it some thought, and investigated the old broken driver, I 'think' it might be because I had some very early modules when 640 first appeared and they drove the diodes individually (originally, in CW/TTL high mode, only one diode worked, which was 'known' by Bridge and later changed)
Certainly, there is a small daughterboard inside the old driver that the burnt diode was connected to, that isn't in the replacement driver.
The fact that i get full power out of the remaining diode at 2.5V mod input suggests the newer drivers are wired in parallel, and the remaining diode is getting 2x the current, now that one is blown. Still doesn't explain why one died completely upon powering up the projector, before any modulation input was applied.... hmmm.
Luckily I have enough spare projectors to do my jobs in September, so we'll see what LW say about it.
This is sad, as I really liked these dual single mode modules, and as I have 2 matched projectors, if this one has to be retired and replaced, I really need to replace both so they continue to match.
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