HELP MetalSimplex Problem!!!

[1tczx]

Got some question bout building this http://www.aronnelson.com/gallery/main.php/v/jpm83s-Gallery/album176/Vero+layouts/metal_simplexlayout.gif.html

Qn1) what is resistor 10kR?
Qn2) what is transistor hfe 170/225 hw do u read it on a transistor?
Qn3) Which side/polarity is the LED facing?

Hope u guys can help me out. Desperate!!
THX in advance,.

[oldrocker]

The 10kR is just a normal 10k resistor.  I wouldn't worry too much about to transitors.  Just use what you have for npn's and experiment.  I used 2N2222's for tannys and a 3mm green LED in mine.  For LED polarity just look which side has the flat edge on the layout. It looks like it's on the bottom connected to R4. That would be the negative lead.

[anchovie]

I'd recommend using schematics in conjunction with layouts, that's where the answers to 1 & 3 were.

[1tczx]

haah thx guys..
got this up but however, theres no sound from it when engaged.. HELP!!
triple checked wiring/sodler joints all ok. so wads the problem?
btw im using MPSA3904 PH07 trannys. issit ok?

[oldrocker]

Check that you cut the copper traces where the red square and dot are.  Make the jumper is there and part orientation is correct.  Especially the trannys.  Yes the tranny types you used should work fine.  Also build an audio probe.  With this circuit and an probe you can find this problem in a few minutes.

[1tczx]

HELP everythings correct.. Checked with my MM and everything.. so wads the problem?

[oldrocker]

Next step?  Yup you guessed it.  Time to get out the audio probe, or build it and learn how to use one.  Then you'll know wad the problem is.  Also as stated above are you following the schematic or just the layout.  Get out the schem and the layout so you know the circuit inside and out. 
By the way.  In your photo it doesn't look like the output jack is grounded.

[1tczx]

grded output.. no diff.. btw how do u use a audio probe? and how do u know that theres a problem at that specific part while probing around?
btw is the LED suppose to light up when i on the efx?mines did.  tot its suppose to be used as diode and not light up?

[anchovie]

Read the DIY FAQ linked just under the forum banner. Audio probe instructions are there.

[1tczx]

ahah thx guys found the problem. the trannys were wrongly placed.. the veros all wrong!!
thx agn guys

[Paul Marossy]

Yeah, gotta watch those transistor pinouts! 

[oldrocker]

Make sure the jumper is there and part orientation is correct.  Especially the trannys.

Transistor and IC pinout are the first things I checkout and understand before starting a build.
Layouts are helpful guides that make it easier to build projects.  But because of differences in manufacturers it's up to to builder to compensate for the components they may use.  And yes some layouts do have errors so don't depend on them as gospel.  Get out the schematic study it and see how well that layout matches it.  It's a pain but worth it when debugging a project.
One last thing “SOCKET THOSE TRANSISTORS”.   Especially in this circuit.  It has different distortion charactoristics with other transistors.  The LED also makes a difference.   If you get a chance try 2N2222's for the npn's and a green LED for less fizzy sound.

[1tczx]

haizz it suddenly stopped working again... check with schemetics corrected errors still no sound from it.. haizz
HELP

[oldrocker]

Audio probe?

[1tczx]

hahah audio probe rocks!! worth making one. found the problems right at the input. thx guys