Group Buy Compact 506 Complete Set

[mixedgas]

Before you change the Redboard tuning, take a nice digital multimeter and measure the trimmer potentiometer resistances as best as you can. Write them down. DO NOT follow the common procedure of zeroing all the potentiometers to one side, per the common tuning instructions. Once you change the AGC loop, damping and Linearity, there is no easy way back without resistance measurements. Those measurements are unique to each board.

Steve

[laserbiker]

Thank you Steve for your good advice. I always measure and record the trimpot settings before I start making adjustments on galvo drivers. That removes the chance of something getting irreparably miss-adjusted. If something goes wrong, I can set them to their original values and try again.
Cheers

[laserbiker]

I just completed my little projector and finally got a chance to test the larger-mirror 506 scanners with my red board drivers.
After recording the values of all the trimpots, I powered it up. To my absolute amazement, they perform the same as my 3mm scanners that these boards were tuned for, which I thought was quite good!
I soon will do some quantitative testing and I will share the results here.
I am sure they can be improved with some tuning...

I would greatly appreciate if someone could post or send me a drawing showing what each pot is for on these red boards.

Thank you in advance

Brian

[JasonB]

Do you have the red board that Mixed Gas provided? If so, I can find the post that describes the pots in the amplifier group buy thread he started around a year ago...

[rns0504]

Is this the same redboard amp that Bill has detailed on the Compact 506 page of the ScannerMAX site?

[mixedgas]

Do you have the red board that Mixed Gas provided? If so, I can find the post that describes the pots in the amplifier group buy thread he started around a year ago...

Here, Page 5. LEAVE THE POSITION SCALE POTENTIOMETER, INPUT GAIN, and POSITION OFFSET POTENTIOMETERS ALONE! They were very carefully calibrated on a test fixture to WRB's specs.
It is easy possible to get this board to oscillate by trying to zero all potentiometers and tune from scratch.

http://www.scannermax.com/pdf/c506_amp_mod.pdf



Steve

[laserbiker]

Thank you Jason B and Ryan.
I am so excited to find that these scanners work like they do. I was not looking forward to a major tuning--something I have not yet done.
There are many great guides here on the forum though, and I am sure some fine tuning will be nice. I have a link to a great tuning guide found on this forum. I will search for the info on the red board layout starting with your suggestions.
Thanks
Brian

[mixedgas]

Ryan,

Yes, its my "REDBOARD"

IF YOU ARE RETUNING:


Pot locations are Here, Page 5.

]http://www.scannermax.com/pdf/c506_amp_mod.pdf


LEAVE THE POSITION SCALE POTENTIOMETER, INPUT GAIN, and POSITION OFFSET POTENTIOMETERS ALONE! They were very carefully calibrated on a test fixture to WRB's specs.
It is easy possible to get this board to oscillate by trying to zero all potentiometers and tune from scratch. Do not follow the advice of a certain tuning guide to zero and start over!


You may also find that another tuning guide's "Three legged stepstool" technique is not so applicable to the damping on these amps, which is likely to be within one turn of where it should be for the new mirrors.


Steve

[laserbiker]

Thank you Mixedgass. and all, for your help
That is exactly what I needed. I will heed your warnings about what not to touch.. One question, Mixedgass, How is it possible for the to appear to work so well with scanner boards not even tuned for this particular mirror size ? Obviously this is a subjective opinion now. Detailed testing and optimization to come.

Brian

[mixedgas]

The 506 has more then enough torque for large mirrors. That is mainly why. Its not "wimpy" like some of its competitors. It is not so susceptable to torsional resonances with that huge rotor diameter.
There are other reasons, such as my scaling the angle response on the amps to a very conservative, small, angle during initial tuning. Generally, nearly all of the REDBOARDS were almost "out" of additional damping when shipped.
I pushed the damping hard, and then backed off one turn to leave some reserve. You may get better linearity, etc, but I would not expect much more speed after a retune.

Redboard tuning done here is a tradeoff between ILDA 30K at 8', good linearity, an excellent 11x11 grid at large angles, and good performance on show I like to watch with very complex animations by Lightspeed.
Do not expect a great Lasermedia pattern with existing tuning, and I would not try for an optimium LM with REDBOARD amps.


Steve