need a fresh pair of eyes.

[foxfire]

so i breadboarded and moded and built this little guy but, it's ended up not being more than a crappy radio. it sounded fricking great on the breadboard. i'm on my third day of trying to get it to work. i'm 99% sure all my work is good so if someone could just take a look at my layout and confirm that it should work? so far all it does is boost the signal a bit and it picks up a radio station as i said above. thanks for any help.

   

[drewl]

Is C2 breaking the ground connection or an emitter bypass cap for Q1?
And why is the ass end of D1 connected to ground, shouldn't it be in series with the supply?

[foxfire]

i believe it is an emitter bypass cap and, i started putting the protection diodes in like that after reading the some of the circuit write ups over at fuzz central.

[anchovie]

Going by this datasheet - http://www.nxp.com/acrobat_download/datasheets/BC847_BC547_SER_6.pdf - the BC547 should be rotated 180 degrees.

[foxfire]

Going by this datasheet - http://www.nxp.com/acrobat_download/datasheets/BC847_BC547_SER_6.pdf - the BC547 should be rotated 180 degrees.

the bc547's that i have are not Philips. so in this case it is in the correct direction. 

[John Lyons]

It looks ok as far as obvious problems. It's different than the Leadfoot schem so it's hard to say.
The 12K on the LF schematic is a negative feedback resistor which will make it less gain to some extent. Oscillation?
I'd audio probe it and see where the signal is weak/dead.
Either that or re bread board it and make sure you got the circuit correct.

How are the voltages?

JOhn

[foxfire]

so my voltages are,

Q1 E-0.758
     B-1.35
     C-2.13
Q2 E-1.479
     B-2.13
     C-6.02
nothing too crazy i don't think and i had already re breadboarded it to double check so i checked them against it and they are all but dead on. so it must be some thing in my work or a bad part somewhere?

[John Lyons]

Hmmm...I'd audio probe it and see where the signal stops. 6 volts is a little high for Q2 collector but it should work at least.
I've been neurotic about testing transistors lately to make sure they work consistantly.. Maybe you popping in a dead one...

John

[foxfire]

alright well i decided to just rebuild it and it works. ta-dah! i must have had a bad part in the first one somewhere. now i just hope it sounds good enough to justify all the time it took. oh well now i can move on to the next one. thanks for the suggestions and help.