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capacitors and transitors have a direction?


hangwire

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??? title says it.

i know resistors dont, but do the capacitors? or do they just all need to be the same direction with the printed values facing the same way?

how about the transistors? on the PC board the outline makes it look like the side that has the middle leg out in front a bit should face that way


thanks smile.gif

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you really need to just post a picture of what you have.


I'd say most brown caps aren't polarized, but if they're tantalum or really old oddball paper caps they might be brown and polarized.


Transistors have three legs and they all need to be in the exact right place in the circuit or they won't work. If you have metal can (silver) transistors that means you have Bipolar Junction Transistors so the three legs are the Emitter, Base and Collector.


You really need to figure out what exact model/kind you have so you can figure out the pinout. They're mostly the same but you can never be totally sure until you've researched it. When beginners are building a circuit, having the transitstor oriented wrong is maybe the most common problem in a non-working build.

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Quote Originally Posted by Reaganomics!

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you really need to just post a picture of what you have.


I'd say most brown caps aren't polarized, but if they're tantalum or really old oddball paper caps they might be brown and polarized.


Transistors have three legs and they all need to be in the exact right place in the circuit or they won't work. If you have metal can (silver) transistors that means you have Bipolar Junction Transistors so the three legs are the Emitter, Base and Collector.


You really need to figure out what exact model/kind you have so you can figure out the pinout. They're mostly the same but you can never be totally sure until you've researched it. When beginners are building a circuit, having the transitstor oriented wrong is maybe the most common problem in a non-working build.

 

no they are new film caps, nothing old or weird


the metal can transistors are not numbered in any way for the legs... all i got is the outline on the board that looks like a backwards "D" and I assume the middle leg that juts out a bit should face that way... so its either that or upside down icon_lol.gif

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Quote Originally Posted by hangwire

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no they are new film caps, nothing old or weird


the metal can transistors are not numbered in any way for the legs... all i got is the outline on the board that looks like a backwards "D" and I assume the middle leg that juts out a bit should face that way... so its either that or upside down icon_lol.gif

 

then that is likely not polarized at all.


As for the transistor, on the board D shape really more indicative of how to orient a black silicon transistor in a TO-92 case. Your transistor is in a different case and I don't know if it's PNP or NPN so the symbol on the board might not be helpful. In pretty much any transistor the middle leg, then one that sits "forward" is almost always in the middle pad on the board so the whole transistor could really face either way. It's the outside ones you have to be sure about.


Who makes the fuzz kit? If I could find more info about their board layout or the schematic I could tell you for sure.


If it's pretty close to the original mosrite fuzzrite circuit it's using an PNP germanium transistor with this layout pins2.gif.


According to the circuit the emitter (e) goes to ground. If you can see the traces on the board and figure out which of the transistor pads connects to the ground then orient it that way.


If we're trusting that the "D" shape follows the traditional silicon NPN layout then the forward leg of your transistor probably faces the curve of the D and the two 'back' legs face the flat part of the D.



 

Quote Originally Posted by hangwire

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also, a 0 ohm resistor that is just serving as a jumper... is it a resistor that is just 1 black line, or could it be a blue cyclinder with a black line ?

 

edit: The blue cylinder is probably a diode. Any 0 ohm resistor I've seen is probably a brown resistor with a black line in the middle of the cylinder.
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Quote Originally Posted by Reaganomics!

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then that is likely not polarized at all.


As for the transistor, on the board D shape really more indicative of how to orient a black silicon transistor in a TO-92 case. Your transistor is in a different case and I don't know if it's PNP or NPN so the symbol on the board might not be helpful. In pretty much any transistor the middle leg, then one that sits "forward" is almost always in the middle pad on the board so the whole transistor could really face either way. It's the outside ones you have to be sure about.


Who makes the fuzz kit? If I could find more info about their board layout or the schematic I could tell you for sure.


If it's pretty close to the original mosrite fuzzrite circuit it's using an PNP germanium transistor with this layout pins2.gif.


According to the circuit the emitter (e) goes to ground. If you can see the traces on the board and figure out which of the transistor pads connects to the ground then orient it that way.


If we're trusting that the "D" shape follows the traditional silicon NPN layout then the forward leg of your transistor probably faces the curve of the D and the two 'back' legs face the flat part of the D.





Yes

 


http://www.generalguitargadgets.com/...8044a841b3e85a


http://www.generalguitargadgets.com/...8044a841b3e85a

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OK so the 2n2369a is an NPN silicon transistor so that circuit is modified from the original fuzzrite. The metal tab that sticks out of the case indicates where the emitter leg. That still goes to ground. You can't see it but the ground is at the bottom of the board as pictured so make sure the transistor leg nearest to that tab is facing down; the 'forward leg' is going to be facing to the right.


Edit: the blue cylinder thing is probably a diode, but GGG website doesn't indicate any diode in that kit so I don't know why it's there


. If you want to be super sure, just save one of the resistor legs you snip off and put it in the jumper spot on the board. It's the same difference as EchoD said.

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Quote Originally Posted by Reaganomics!

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There's no diode in that kit so that's probably the jumper. If you want to be sure make sure the jumper is the last thing you put in, and that blue thing will likely be leftover. If you want to be super sure, just save one of the resistor legs you snip off and put it in the jumper spot on the board. It's the same difference as EchoD said.

 

It looks like on the PCB there's a spot for "D1" which should be where that diode goes. Match up the stripe on the diode with the stripe on the PCB. Easy peasy.
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Quote Originally Posted by AluminumFalcon

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It looks like on the PCB there's a spot for "D1" which should be where that diode goes. Match up the stripe on the diode with the stripe on the PCB. Easy peasy.

 

its not in the bill of materials and not in the wiring diargam [the board is only half populated]
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It appears to be a polarity protection diode based on the wiring diagram showing the PCB traces. Go ahead and toss it in there.

 

 

does it matter which direction since it is just jumpering?

 

also, seems tab side should face down as the pic shows as emiter would be lower leg

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