Printable View
I am replacing my 30K scanners with DT-40 Pro`s. they come with a pot for gain control. you can connect the input to the amps with either _ signal or + signal can anybody tell me which way I need to connect it to work with EasyLase dac?
Also the X and Y input to the amps use a common ground should they just go to pin 25 instead of 14 and 15?
Here is the PDF.
http://www.dtelectronic.cn/DT-40proUserManual.pdf
Look at terminal J-1 and see if the two middle terminals are bridged. Looks like the Dsub 25 pin cable MAY wire as follows::: X pos signal from pin 1........14 is X gnd. Pin 2 is Y pos.......pin 15 is Y gnd. The pair of X signals going to X axis driver amp and the pair of Y signals going to the other amp for the Y axis. You might want to check me here as I have not had the chance to get a set of these guys. I would bet Spec would know for sure. It doesn't look like a single ended setup. Marconi may have input here as well. They just don't seem to give all the info needed ...I am still looking over the pages..................
Quote:
Originally Posted by MechEng3
The problem is the Input has only one shared ground for both X and Y.
:idea: Looks like you will have to set it up as a single ended connection.If this is how you set it up don't forget to use 4.7 K ohm pulldown resistors on the grounds! See the Easylaseinterface manual, pages 8 and 11. If you don't have the manual . The outlines were available on JMLaser's web site. If you can't locate it let me know and I can send you a copy on Thanksgiving day. Still I would ask Spec to step in here....I know he has used this scanner set.
Dont the DT40pro's have seperate amps for the x and y?
Just reading your post again I think you meen do you need to use the ground on the amp inputs.
Just connect pin1 of the DB25 to the + pin of J1 and pin14 to the - pin of J1 on the X amp, then pin2 to the + pin of J1 and pin 15 to the - pin on the Y amp.
Ignore the G pins.
Jim
Ok, I am not sure I explained the problem so here are some pictures. This is the cable-pot supplied with the system and the input on the amp.
http://www.pbase.com/astroguy/image/70644577.jpg
http://www.pbase.com/astroguy/image/70644578.jpg
http://www.pbase.com/astroguy/image/70644836.jpg
As you can see there is only one ground for both X and Y going to the ilda.
And there is only two ways to plug the cable onto the amp.
Easylase: Connect X- and Y- together to Pin 25 (Easylase GND). Connect the 3 signals (X+, Y+ and GND) to the DT40 Pro cable. Red=X, White=Y, Black=GND.
Connect the small plugs to the right 2 pins. ("Gnd" and "Signal-"). Leave the left two disconnected! this is the right way! I hope you understand me.
Greetings
I think so. The conector with the X+ Y+ and ground. I take that ground and connect to pin 25. X+ and Y+ to pins 1 and 2 and no conection to pins 14 and 15?Quote:
Originally Posted by Starburst
Fred;
Have a look at Starburst's post again. He said to connect pins 14 and 15 (X - and Y -) to the ground on pin 25, which is the common ground. Thus your X and Y grounds will be common to pin 25.
Like Mecheng3 said, this makes it a single-ended connection. (Much like the F2000 unit that Dreambeamz has...) Not sure where those 4.7 K resistors are supposed to go though. (Between pin 14 and ground and pin 15 and ground?)
MechEng - would you elaborate?
This is basically the direction we were headed last night. Nice to have some more input though!
Adam
the 4k7 resistors are not needed with easylase! The resistors are only to protect other cards.