looking for CScope 660 schematic

[hugo]

Thank you Davor for sharing your knowledge. I wonder if there is a thing you don't know !
You are a valuable master on this website.

[Davor]

You are exaggerating. I'd become valuable with much more lab time, but it must wait - there are some other priorities.

[smity]

Hi! The depth at which the device will see the 1 euro coin?

[hugo]

@Davor : I really thought what I said
@Smity : No more than 15cm, but quite good discrimination

[Rumcajs]

Many thx.

http://pl.wikipedia.org/wiki/Rumcajs

[Guzzi]

Hi all

I working on this CSCope 660 schematic. I made a PCB, so far no problem.
I have a 17.7 KHz sinus on the TX but after D1 nothing. Is there a mistake in the schematic, i can not find it.

regards

Leendert

[dbanner]

Hi allI working on this CSCope 660 schematic. I made a PCB, so far no problem.I have a 17.7 KHz sinus on the TX but after D1 nothing. Is there a mistake in the schematic, i can not find it.regardsLeendert

Did you use original PCB layout or did you make your own layout?

[dbanner]

Remove anode leg of D1 from circuit and check again the signal at anode. You should see a signal. If no signal, then problem is before D1 with the trimmer preset and discrimination pot.
If you have a signal, then problem with R20, R22 and Q4.

[Guzzi]

I used the photo of the PCB from Hugo in Sprint Layout. Then i made the drawing in Sprint.
The pictures are not complete so i had to use my imagination and the schematic.
I have a nice signal(sinus) from the TX but nothing after D1. That is the problem, the diode is not conducting.
Even without Q4 there is no signal after D1.

[dbanner]

Well ok. I will check my layout to make sure the connections around D1. I will compare to the schematic to see what's wrong. Get back to you in a few minutes.

[dbanner]

Here is a pic of my Sprint layout of the section was involving D1 and surrounding connection. Have a look and compare to yours.

[dbanner]

You should have a signal on the cathode of the diode. Right?

[Guzzi]

Hi dbanner

I found it, i had made a mistake on the PCB and over looked it many times. But with the help of your pictures i found it,
Many thanks from the Netherlands.

Regards

Leendert

[dbanner]

Great.Let us know how it works out.Any more questions are welcome.

[walkman]

Here is a pic of my Sprint layout of the section was involving D1 and surrounding connection. Have a look and compare to yours.

dear friend,
Can you CScope 660 share sprint layout files please