DT-40 Pro's .. potentiometer

[Pitts]

Hi guys,

My nice new DT-40 Pro has arrived from Jian as has my really nice 1700mw green (doing 1900+) even has its own fan ...from Aijii..
This thing is like a searchlight and I havnt even turned it up yet. Looking forward to getting the PT40 running when my Pangolin system gets out of the grips of our Customs.
My question is with the PT40 it came with two leads attached to a potentiometer. The two plugs fitted seem to fit the input connector (X&Y) but I assume the input connectors go to the Pangolin board ILDA.
What does this pot do ?? I have asked Jian and he has promptly replied to my emails but I don't think he understands what I am asking.
Is it for testing ? do I use it when I am connected to the ILDA or not ??
The manual is so basic it doesn't even mention the "pot on a lead".
I saw the thread by Banthai really good info on there on the PT40 but still nothing about the pot even though Banthai asked...... a mystery !!!.

By the way is it safe to power up the galvo without the ILDA connected ?
If so what will happen if anything ?? (is this what the pot does ?)
Thanks

Ray
NZ

[dave]

discussed here:

http://www.photonlexicon.com/forums/...ead.php?t=2266

[Pitts]

Thanks Dave.
Although the thread doesn't exactly address the potentiometer as such there is a picture which helps. (thats a real helpful article on the DT40)
I assume the "third" wire is the ILDA connect point ??
Does this pot do some form of X & Y balance ratio ??
Thanks
Ray

[dave]

The pot is simply a size control.

since you will be using pangolin, don't use the pot, as you wont be taking advantage of the differential signals coming from your qm2000. And besides, you have access to scan size controls in Pangolin's pr zone window.


yadda posted here:

If you have a differential controller:
attach pin 1 to the leftmost pin on INPUT on the X scanamp,
attach pin 14 to the rightmost pin on INPUT on the X scanamp,
attach pin 25 to one of the inner pins on the X scanamp.
attach pin 2 to the leftmost pin on INPUT on the Y scanamp,
attach pin 15 to the rightmost pin on INPUT on the Y scanamp,
attach pin 25 to one of the inner pins on the Y scanamp.
(Note that while normally you do not want to route pin 25 to a differential amp, due to some internal details the DT40's will probably thank you for it.)

[platinum]

I'm looking for consensus on this particular aspect of the DT-40 Pros.

I'm wiring one right now and I can't seem to find more than one definite opinion about whether or not the potentiometer is needed.

I'll be using the Flashback 3 with my DT-40s.

Is it necessary in this situation? If so, how exactly do I wire it? I can't find a pinout anywhere...

[p1t8ull]

As Dave said above, the pot is just for manual scan size control when using a controller with single ended X/Y outputs.

It all depends on how you are planning to use the laser... If you're only ever using the FB3, and in stand-alone mode then installing the pot will make quick scan size adjustments easy.

If you will always be using the FB3 with a PC then you don't need the pot as you can adjust the scan size in software.
If you ever want to make use of the differential outputs of another controller (ie QM2000) you shouldn't install the pot. It'll work ok, but will reduce the signal to single ended.

It's your call.

[cruch]

Maby someone should make an pinout for the DT40 Pro's for
single ended and differential outputs

[platinum]

Maby someone should make an pinout for the DT40 Pro's for
single ended and differential outputs

Thanks to Jian including exactly that, I was finally able to wrap my head around the wiring and get my scanner running about an hour ago.

Now I need to deal with the flicker. (...probably shouldn't be using this serial cable with a gender changer.. )

-Jonathan

[cruch]

single ended / differential outputs for DT40 Pro's