BARACUDA-Legend-1

[Wilson]

Hello Mohandes, good news you missed two resistors, the correct is 1K and 10K you installed.
The gain was reduced from 1000 to 100 times.

[Fabian]

According to cross-reference data, BF256B and BF256C seems good. Check it out (and you should use this tool more often! ):

2N5485 replacements:

http://alltransistors.com/mosfet/crsearch.php?struct=FET&polarity=N&pd=0&uds=25&ugs=0&id=0.01&tj=150&fr=0&cd=1&rds=0&caps=TO92&page=0

Fabian

[bion]

Try this Q1=TIP127. Q2=PN2222. Q4 and Q5- BF245C. Q3:BF256. Q6=Bc517.This is mi configuration.

[mohandes]

[QUOTE=Wilson;177961]Mohandes, I would like to find issues to help you, unfortunately I do not know what else to do, I hope that some friend of the forum to analyze the entire content displayed here and can see the problem to help you.
Good luck: Good
thanks man you are realy the good friend and you are in my heart.
and the final information:
my speaker is 32ohm(and 8ohm too)
complete name of 7660 :7660scpaz


Fabian thanks it is ok , i was wrong in wrote .

and final idea , maybe the equivalent transistor dont work well.except bf256 that instead of 2n5485 ,i change all to bf245c(instead of the mpf102),Nice????

[Fabian]

Capacitor

Hello Mohandes: In your photo, Cap 11 has an incorrect value. Must be 100nF.

Greetings.

Fabian

[Wilson]

Mohandes, I would like to find issues to help you, unfortunately I do not know what else to do, I hope that some friend of the forum to analyze the entire content displayed here and can see the problem to help you.
Good luck: Good




Desfazer edições

Alpha

[mohandes]

Mohandes, the image with capacitor C16 470nF this wrong, I could not remove after editing.

Hi
all is ok , this is big ? for me.why ?????

[Wilson]

Mohandes, the image with capacitor C16 470nF this wrong, I could not remove after editing.

[Wilson]

Hello Mohandes, the voltage at the gate of Q7 is below the voltage in my circuit, check picture as below.
The tension of this coil is low, check your coils or mosfet.

[mohandes]

I find error guide me please

ok
i think this error in Q7 look the pic. please tell me where is my error ?? i use bf256 but i have another equivalent transistors like :BF256b , BF245b , 2n3819 .maybe this error for my equivalent or no , so where?

[Wilson]

Mohandes Hello, I'm sorry, the forum has different schemes using or not the fet with SW1. I consulted the scheme that does not have this fet but your PCB uses the Q5, I asked to remove the previous post. In the picture below I explained correct.
The pictures I posted # 976 I missed in naming Q5, Q7 is correct.

[mohandes]

Hi mr wilson
ok,i put for you all waves BUT you say REMOVE THE Q5, so for your request i solder it in my board and then measurement all:
see waves like you to COLLOCATION :





hemmmm,Q5 no have no signal maybe have problem , any idea??

[Wilson]

Mohandes, check the waveforms in your circuit ok.

[Wilson]

Hello Mohandes, check the components and pcb tracks inside the square in red, you are using the transistor right? 2N2222A, make sure the position is correct base, collector and emitter. Check with oscliloscópio collector Q2 (2N2222A) and post the image.

[maikl]

mohandes
Original coli inductance 453 uH and resistance R=1,4 and nice to work with other coils... for example 350uH and R=2... which means Barracuda is very tolerant regarding coils.
It is also very tolerant detector as for other electronic components (provided that the correct)... here are some replacement working well: Q1=IRF9640, Q3=Q4=Q5=Q7=BF256, U4=LM358...
My only advice is to play a game with the damping resistor and change of speaker, if that does not work then it's your maximum!
I see you've started and other detectors that are a lot more complicated than this, I think it is for you to "mission impossible"...