Just looked at this video.
https://www.youtube.com/watch?v=FfPrCWvAflk
Looks like it's AC input, but that often implies a center tap as well. If the schematic doesn't help, look at the little round black plastic thing between the power plug and the big caps. Two of those leads will go to the plug. Each of them is AC input.
There may be a 3rd conductor for ground as well.
Best,
E
https://www.youtube.com/watch?v=FfPrCWvAflk
Looks like it's AC input, but that often implies a center tap as well. If the schematic doesn't help, look at the little round black plastic thing between the power plug and the big caps. Two of those leads will go to the plug. Each of them is AC input.
There may be a 3rd conductor for ground as well.
Best,
E
The external supply should provide 2 AC lines and one ground. You can test if uncertain because the 2 AC lines should provide maximum AC voltage between them, but an AC to GND will be half. For instance, the 2 AC wires will measure 24V, but if you measure AC to GND you will get 12V or 0V (if the output is split).
Without a schematic, we have to work our way backwards from the bridge rectifier in the Kube. Here's a pic of a similar bridge rectifier that I saw in the video, located right before the DIN connector:
It may be a good idea to test the rectifier itself if your meter includes a diode tester. A short in the bridge rectifier can fry your power supply, and an open diode will cut the DC voltage inside, cheap to replace if needed. Here is a video. You do not have to take it out of the circuit:
YouTube
Notice that the picture has markings for (+) and (-) on the top and bottom pins. Those are on the "inside" of the circuit, so not what we need to find the right inputs on the DIN connector. They are the DC outputs and go to the big filter caps and eventually the voltage regulators.
What we need are to connect the AC voltage from your supply to the AC inputs of the rectifier. Those pins are labeled with AC wave symbols, and are reversible. In this picture they are on the right and left. So, knowing this, you then can test continuity between either AC input on the rectifier to the DIN socket.
Remaining DIN pins will likely be tied together to ground.
If your power supply has 4 wires coming out of it be careful you don't invert the connections. Use your AC meter to ensure you know the outer winding vs. the center tap and ground and don't get them confused.
Best,
E
Without a schematic, we have to work our way backwards from the bridge rectifier in the Kube. Here's a pic of a similar bridge rectifier that I saw in the video, located right before the DIN connector:
It may be a good idea to test the rectifier itself if your meter includes a diode tester. A short in the bridge rectifier can fry your power supply, and an open diode will cut the DC voltage inside, cheap to replace if needed. Here is a video. You do not have to take it out of the circuit:
YouTube
Notice that the picture has markings for (+) and (-) on the top and bottom pins. Those are on the "inside" of the circuit, so not what we need to find the right inputs on the DIN connector. They are the DC outputs and go to the big filter caps and eventually the voltage regulators.
What we need are to connect the AC voltage from your supply to the AC inputs of the rectifier. Those pins are labeled with AC wave symbols, and are reversible. In this picture they are on the right and left. So, knowing this, you then can test continuity between either AC input on the rectifier to the DIN socket.
Remaining DIN pins will likely be tied together to ground.
If your power supply has 4 wires coming out of it be careful you don't invert the connections. Use your AC meter to ensure you know the outer winding vs. the center tap and ground and don't get them confused.
Best,
E
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Here's a good picture of what is going on. Notice the right side of the transformer has 3 lines, with the center being ground. In this case the inputs to the bridge rectifier are unmarked, but the outputs (+ and -) are marked:
Also take advantage of any "doubling up" of input pins. If you notice 2 pins on each leg of the AC input are tied together on the circuit board, take advantage by using both. This will increase reliability and reduce the potential for contact resistance.
So if unsure about the ground, notice the big caps all tie together there. To the right of this diagram is where you would find the voltage regulators and additional filtering.
Best,
E
Also take advantage of any "doubling up" of input pins. If you notice 2 pins on each leg of the AC input are tied together on the circuit board, take advantage by using both. This will increase reliability and reduce the potential for contact resistance.
So if unsure about the ground, notice the big caps all tie together there. To the right of this diagram is where you would find the voltage regulators and additional filtering.
Best,
E
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I just received an Sp2080 (Kube 104/2), sans power supply, with a pair of 104s I picked up this past weekend.
I can't attach photos here but there are 4 wires off the DIN connector. 2 go to ground, and 2 go to the AC inputs of the GI W02 single phase bridge rectifier. Simple enough, but nothing tells me what voltage I need to be bringing into the box. Information here and elsewhere seems unclear. 18V or 23V, and is that rail to rail or rail to ground? Does anyone know for sure it based on experience?
Thanks
Dan
I can't attach photos here but there are 4 wires off the DIN connector. 2 go to ground, and 2 go to the AC inputs of the GI W02 single phase bridge rectifier. Simple enough, but nothing tells me what voltage I need to be bringing into the box. Information here and elsewhere seems unclear. 18V or 23V, and is that rail to rail or rail to ground? Does anyone know for sure it based on experience?
Thanks
Dan
Find the voltage regulators. They will give you a clue, since you'll want the supply a couple of volts above this. They are the big transistor like devices just inside the big filter caps. I think one is labeled IC5. My guess it they will be 78 or 79 LM15, i.e. 15 V regulators. You'll want a transformer that charges the filter caps to a couple of volts above this. 18-20V should be fine.
Best,
E
Best,
E
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