daguin
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- Joined
- Mar 29, 2008
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Hey Dave,
Since the normal safe operating current is 7A and the PSU can only supply 10.5A I decided to redesign the remote schematic. I have implemented a switch that allows for continuous variable current control or a fixed current level - set at 7A. The variable control tops off at a little under one amp less than the maximum the PSU can deliver, for tube safety and longevity. I decided to leave out the DPDT switch feature that allows for an optical feedback based power control, as I have no desire for it, but it can easily be implemented as in the original feedback. I simply jumpered the connection that normally switches between "light mode" and "current mode" into the current position. Total current draw from the 15V pin is kept to under 15mA, well within the 20mA specification of the manual.
I will for sure be using this set up when the laser arrives, so that will be the first official test, but I see no reason why it would malfunction. It is essentially identical to the schematic on LASERFAQ.
By the way, there is an error on the LASERFAQ page for this remote; the ascii schematic shows a 1.5k ohm potentiometer and a 1k resistor. If this is used the pot will allow adjustment up to a potential of ~18amps, not the normal 12A that having a 1.5k resistor and 1k pot allows. The verbal description is correct, but the resistances in the drawing are reversed. I nearly ordered the wrong size pot as a result. If I had not asked you about nominal operating currents and then decided to redesign the remote to change the operating range and function I would not have caught the error.
Please feel free to use this schematic wherever you would like in the future. A (truly) small token of my thanks. Hopefully it helps others.
VERY COOL! :thanks:
Peace,
dave