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Author Topic: SCHEMATICS  (Read 13976 times)

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alm

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Re: SCHEMATICS
« Reply #25 on: December 24, 2012, 03:27:07 pm »
Could you post this answer for the benefit of anyone with the same problem stumbling on this thread via Google?
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #26 on: December 24, 2012, 03:31:23 pm »
Replacing the Lcd display.
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #27 on: January 03, 2013, 07:46:24 pm »
Hi guys! Help me with this one. What is the value of this rezistor? The first line is grey the second is green. THX!
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Offline PA0PBZ

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Re: SCHEMATICS
« Reply #28 on: January 03, 2013, 07:52:37 pm »
The picture is not very good but it could be a diode, not a resistor.
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Offline SeanB

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Re: SCHEMATICS
« Reply #29 on: January 03, 2013, 08:02:44 pm »
Looks more brown, which makes it a 150kohm resistor, which is a preferred value. Probably 1/8W 10% as well. They are rather infamous for going quietly open circuit.
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #30 on: January 03, 2013, 08:05:01 pm »
Not brown.. it s grey. Wow!... i ve never seen a diode like this. True it cross my mind..that it could be a diode.. but the colours? Is the older version of the 1N4148?
L.E. the board has 1N4148 on it.
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Offline SeanB

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Re: SCHEMATICS
« Reply #31 on: January 03, 2013, 08:14:29 pm »
Remove one, measure resistance both ways and see. Break it and you will be sure, white is a resistor while glass with black shiny inside it was a diode.
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #32 on: January 03, 2013, 08:30:07 pm »
Now this is odd... the values oh the rezistance are different: 1.272 Kohm .. from the other end 04,60Kohm. And on the diode meter is 0,222 volts from green to grey... closed circuit from the grey to green. Inside like the 1N4148.. glass with redlike colour... all this under the white paint with grey an green stripes..
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Offline jeroen74

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Re: SCHEMATICS
« Reply #33 on: January 03, 2013, 08:38:50 pm »
Not a zener by any chance with the colour code indicating the voltage?
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #34 on: January 03, 2013, 08:48:03 pm »
Highly like... a zener with colour code ...1N85 maybe?
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Offline PA0PBZ

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Re: SCHEMATICS
« Reply #35 on: January 03, 2013, 09:11:20 pm »
Quote from: Sagat on January 03, 2013, 08:30:07 pm
Now this is odd... the values oh the rezistance are different: 1.272 Kohm .. from the other end 04,60Kohm. And on the diode meter is 0,222 volts from green to grey... closed circuit from the grey to green. Inside like the 1N4148.. glass with redlike colour... all this under the white paint with grey an green stripes..
Did you measure this with one pin disconnected from the pcb? Do they both read the same?
And since you were looking to find out what it is, do you have any reason to think they are defective?
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #36 on: January 03, 2013, 09:15:12 pm »
The component is remove from the pcb.. they dont read the same.. and im just confused.. is it a zener or a rezistor.
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Offline PA0PBZ

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Re: SCHEMATICS
« Reply #37 on: January 03, 2013, 09:29:05 pm »
If you measure these values when removed from the pcb, and it changes with the direction you measure, it is certainly not a resistor.
Looks like it was a diode in better times, to find out what exactly it was you may have to draw some diagrams on how it is used in the circuit.
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #38 on: January 07, 2013, 03:33:24 pm »
Hi guys!
Does anyone recognize this component, or have a better program for a replacement unit?
Ive this to improvize something with a couple of BC s PNP/NPN, 1k, 10k and 47Kohms rezistors but im not sure that are the proper values.
Thx!
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Offline jeroen74

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Re: SCHEMATICS
« Reply #39 on: January 07, 2013, 04:20:50 pm »
Looks like an optocoupler to me. These often come in 6 pin packages and your widget being a MIDI device which requires an optocoupler in its receive part it seems quite logical to me.

Oh, and you cannot replace it with a couple BJTs ;)
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #40 on: January 07, 2013, 04:23:36 pm »
Will a CNX83A or a CNY17/3 do the trick also?
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Offline jeroen74

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Re: SCHEMATICS
« Reply #41 on: January 07, 2013, 04:29:37 pm »
You need a fairly fast optocoupler. The usual device is a 6N138 or PC900. I have no idea what the part# of this one is.
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Offline PA0PBZ

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Re: SCHEMATICS
« Reply #42 on: January 07, 2013, 08:49:24 pm »
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Offline SagatTopic starter

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Re: SCHEMATICS
« Reply #43 on: January 11, 2013, 08:36:28 am »
Many Thanks.
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