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Need high voltage/current DC with adjustable frequency

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Are you sure all 3 of those are caps?

Well, we only speak from many years of experience. I suppose it is possible that the manufacturer has obtained an order of unmarked resistors coloured the same as ceramic capacitors.

Of course, in that case, you can hardly expect to believe that the IC marked as a 555 is actually a 555, or that those devices which look like diodes are not inductors.

Me, I'd go with the beige to brown looking components being ceramic capacitors. I'm probably only 99.9% certain.

Oh, and (again, speaking from experience only) the values of the capacitors cannot be determined by what they look like. It is entirely possible that all 5 have different values. In fact, I'd be surprised if more than 2 of them have the same value.
 

davenn

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Are you sure all 3 of those are caps?

As Steve said ... Years of experience working on this stuff day after day
I can see a number of SMD resistors on the board. 3 I can read are 2 x 104 = 100k and 1 x 4R7 = 4.7 Ohms
 

supak111

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Im not saying your are wrong guys. I'm a newbe so don't get mad. I only asked because from 555 diagrams I found online I see people connect pin 6 to a cap and an resistor from pin 7. And from what I understand changing the resistance from pin7 to pin6 changes the frequency which is why I though those CAPs that are connected to the micro switches should be/ might be resistors.

How can they only have CAPs connected to pin 6? Does anyone have a 555 diagram of a circuit where pin 6 only has caps to it and no resistor?

PS one other thing, so in the pic below now I now the orange is caps, blue is resistors.

Whats the stuff in red? Maybe small diodes?

top.jpg
 
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(*steve*)

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1) are there comments on the other side of the board?

2) do you see that trace coming from under the chip to the resistors? Is that connected to pin 6.
 

supak111

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Yes the trace from the micro switches goes to those 2 caps, dont see any resistor trace going to the pin 6. And no components on the bottom. Here is a picture

bottom_mirror_up_down.jpg
 

supak111

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PS one other thing, so in the pic below now I now the orange is caps, blue is resistors.

Whats the stuff in red? Maybe small diodes?

top.jpg
 

supak111

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Here is what I've traced. Ground --> to 1 big diode --> to both switches --> each switch goes to those 1 cap, and than into the pin 6 on 555. 3rd cap is always connected to the pin 6 and other side of it receives ground.

freq_marks.jpg
 

(*steve*)

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Do you see the trace coming from under the bottom of the chip that you have ignored?
 
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