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newbe please help with PCB symbols

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sa321

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Hello, sorry for an easy question but i want to make it right from first try. I have downloaded the attached pcb schematics. I understood almost all components except the ones in upper right hand corner where it has: LED, 560, 1k and a gray line. (there is no way to contact the author of this). Am I correct to read that LED is placed where the "bent" cicrlce is and 560 is a 560 Ohm resisto while grey line is a jumper?

many thanks in advance
 

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That's how I would interpret it. The grey lines are either jumpers or connections on the other layer of a two-layer board.
 
one gray line that is appearing vertical can be a track on other layer, the horizontal one might be a fuse or pcb track to fuction as a fuse.
 
hm, thank you. i think i ll put a fuse there just in case. many thanks. what a pain to solder this thing
 
hm, thank you. i think i ll put a fuse there just in case. many thanks. what a pain to solder this thing
hi,
Its not a fuse, its a piece of jumper wire, placed on the non-component side of the pcb.
Tinned copper wire, say 22 or 24swg is ok for links.

EDIT:
I see that its a PCB from commercial product also its SMT and thru hole components.
This means you will have to top solder the leads of the thru hole components and place the jumper links on the opposite face of the PCB.
 
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I can understand having a jumper wire where it is vertical but the one that is horizontal, why not just put a trace? there is nothing in the way!

Edit: Looking closely at this PCB, where does the supply connect to? I'd bet the mystery is in that gray horizontal trace?

2nd Edit: I guess supply comes from +B sorry for my newbie analytic eyes.

Mike
 
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agree, there is nothing on the way and it is kind of weird jumper, i put this thing together and it doesnt work. not sure how to even start troubleshooting.

one other question: L9637D component which i bought from future electronics had no markings on (even though on spec file it shows markings). Am I correct to assume that where that gray dot is the same side as where the logo on the component?
 
The grey dot indicates pin 1. So yes, most probably the same as on the component, as some have a small 'dent', others just have a white/gray dot printed on the chip. That means that both chips on the board have the same orientation.
 
http://www.eeworld.com/uploadfile/designarticles/uploadfile/200802/20080217111903295.gif

http://obrazki.elektroda.net/50_1255771873.jpg

Note how pin 7 of the L9637D is connected to '+B', which is 12V, the trace under the grey jumper at the top connects to this.

Update no3. lol, Just noticed the LED is connected between the IN and OUT of the regulator, via a series resistor (1k). As IN is 12V and OUT is 5V, thats 7v. It appears the LED is the wrong way around on the PCB.

You can of course just connect the 1k SMT resistor (next to the LED) to GND instead of IN.
Let me know if you want a schem to go with this PCB
 
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thank you, i was looking at this more closely (though this is my first pcb so i am clueless for most part) and figured LED is marked wrong, just as you said. upper right hand corner looks all screwed up to me. LED suppose to show presence of +5v. why not connect it between 7805 "out" and ground with resistor? why have a jumper when there is trace right next to it? in any case, i put LED as it suppose to be and the entire thing worked!!! i am very happy and proud. no idea how long it will work but i made three just in case
 
Good man! I'm sure the circuit will last a long time, there doesn't seem to be anything on there that uses up any significant power, but as with all things automotive, the rather noisy 12V line can fry some regulators with high voltage spikes. The good 'ol 7805 tends to be rather resilient though. Congratulations :)
 
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