Please HELP! Synrad control

[zoltan]

Hi,

Is there somebody you built a control board for Synrad tube or is there somebody who can tell me what this board must do or is there somebody who can help with a schematics of such a control board. I would like to build a CNC laser with a used synrad tube. The control board is doing the connection between PC and the RF driver of the tube. Through it the PWM is sent for modulating the output. I have no idea how to build this control board. Please, help me.

Thank you.

Zoltan

[tbilalis]

I believe that you just have to on or off (5V) some pin on the Synrad power supply (28V to 48V) in order to power on or off the laser according to your G-code.

What Synrad model do you have? Is it water or air cooled?

tbilalis

[dar303]

Is it a Synrad J48 series laser?
There is a 9 pole dsub connector that has some control inputs ans also a CTRL BNC jack.

From the manual
"The CTRL connector is a BNC-style jack that accepts the Command input control signal. The output of the UC-1000 Controller is attached to this connector. For pure CW operation, a steady +5V signal can be applied through this connector."

The original controller (UC-1000) sends two control signals, a 5khz PWM-signal and a 5khz 1us "tickle" signal that is used to ionize the gas so it responds faster to PWM changes.

Therefore you need some electronics to generate these two signals.

If you use MACH3 then I think that program can generate the necessary PWM signals, just search the MAC forum at www.macsupport.com/forum.

Another way of doing it would be to use two ordinary NE555 timers both set up to generate 5khz squarwaves, one with a 1us pulsewith and and the other set up for varying pulsewith and then control the second one with any card that outputs a varying voltage used for spindle speed control (such as the ones found at www.cnc4pc.com).
The NE555 schematics could propably be used straight from the datasheets or found using google, the 555 is one of the most common IC's used in hobby projects of all kinds found on the web.

I hope I got this right, just ask if you need clarifications!

[zoltan]

Hi,

Thank you both of you. The laser is J48-5SW. I have bought on e-bay from Germany but till now despite the fact that I made a bank transfer the seller is telling me just stories about the shipping of laser. I hope is not a scam as he asked me to transfer the money into a bank account of some relative of him as he said. He sent me tracking numbers of DHL but these are not working with DHL tracking system. Anyway, he still lists two Synrad on e-bay, one of 50W and one of 10W. The system I paid is water cooled.

I am afraid that the UC1000 is more complex that 2X555 timers. I do not want to experiment with this Synrad...if it really comes. If the seller is honest the laser should arrive no later than Monday, if not, I must ask Police what I must do, and I think I must inform e-bay.

Zoltan

[dar303]

I hope you don't get scammed, what a nightmare!
I know the UC-1000 is more complex than a couple of timers but I'm quite positive you could run it of this if you don't have a UC!
I'm hoping to aquire a 48-1 in the future and will of course put my money where my mouth is and test this!

[zoltan]

Hi,

Thank you. Do you have any schematics with 555 to propose?
Zoltan

[jrj5x5]

Originally Posted by zoltan Hi, Thank you. Do you have any schematics with 555 to propose? Zoltan

talk about a major time laps between posts.
holy time warp batman.

[dar303]

Here is the operators manual/service manual for synrad 48-1-28(W), 48-2-28(W), 48-5-28(W) where good info about control signals and schematics can be found:
Read from 2.4.1 for info on tickle and PWM
http://shorl.com/gribubemyforu

Datasheet for Ne555:
http://www.fairchildsemi.com/ds/LM%2FLM555.pdf

A good appnote:
http://www.doctronics.co.uk/pdf_files/555an.pdf

Since both signals are on the same connector and should be present at the same time it may be possible to use one 555 set at 5khz with a pulsewith of 1us and then change the pulsewith to PWM it, taking care that the minimum pulsewith is 1us (tickle) with no modulation present.

[zoltan]

Hi,

Thank you very much.

Zoltan

[zoltan]

Hi,

I have news. Finally, the laser arrived. I was not scammed. The seller proved to be honest but very difficult to get answers from him by e-mail. The laser is huge. I hope is functioning as I was told. I need a power supply 30V/30A. I am in the process of building it. I got an UC-1000 which I wait to arrive. If I have this one I will repair the other one by comparison. Hope that shortly I will fire the laser, and then to find out a solution to mount on my CNC router.

Zoltan

[KTP]

Hey Zoltan,

I also purchased two 50 watt Synrad lasers off ebay awhile ago, both were non-working. Fortunately these lasers are not that hard to repair and I was able to fix both of them (one had a blown MRF-150 RF mosfet and the other had several fried chips on the driver board I had to replace). They now do around 62 watts each, which is pretty good. I have a spare 30V 30 amp power supply and UC-1000 controller if you happen to live near Seattle, WA

The controller is very simple..either you can do what other suggested and use two 555 timers (which is almost exactly what is in the UC-1000 btw...imagine that, two $0.99 parts from radio shack, a few resistors and knobs and it sells used on ebay for over $500!) or you can program up any 8-bit microcontroller to generate the tickle pulse for you. For example, I programmed an atmel AVR microcontroller to generate the tickle pulse and also to listen in on a z axis signal from the parallel port. If the direction bit were positive it would turn the laser on and if it was negative it would turn it off. Also, I used the counter input to register step pulses to set a power level. ie, if you sent 50 pulses with the direction bit positive it would set the laser power level to 50%. This made it very easy to interface to Mach2, although I am guessing now there is some laser support in Mach3 so this would now be a silly way of doing things?

Anyway, good luck getting it up and running, and let me know if you have any problems. There are quite a few tricks you can do if things don't seem to be working right. For one thing, the 48-5 is comprised of two identical 25 watt tubes with separate RF drivers. Thus if you have a tube that is only outputting 20 to 30 watts, it is entirely possible that one of the two tubes is not working. Since the problem is more likely in the electronics than the tube (these tubes seem to last ages), you can do some creative swapping of RF drivers to see if the other tube also outputs 20-30 watts. Then it is just a matter of fixing the bad electronics and you are good to go. Also, while testing you can BRIEFLY run the laser without water cooling, as there is a large amount of aluminum that heatsinks the tubes. What I mean is you can turn on the laser for 30 sec or so to see if you are getting output and then turn it off and let it sit for several minutes to cool down. This is not something you would want to do with a glass tube high voltage laser btw.

There is so much more I could write about these lasers, but maybe yours just works straight out of the ebay box and you don't need to know all this.

good luck!

[zoltan]

Hi,

Thank you for replying to my post. I have tried to get in touch with you but did not suceeded. I need your help. I would like to send you an e-mail. If you agree to send you an e-mail, please, pm with your e-mail address. I have a lot of questions to ask and hope you can help me.

Thank you very much.

Zoltan