BARACUDA-Legend-1

[qute1]

looks like there is a resistor or other missing from next to transistor (top right as it opens in browser)IMG_20180616_204000[1].jpg

[Qiaozhi]

[ATTACH]43357[/ATTACH]today i put together this bara (my first MD ever) and it did not even make a sound. coil 0.25mm 18cm 32 turns. Power 12V DC (two 9V batteries reduced to 12v).
[ATTACH]43356[/ATTACH]
[ATTACH]43355[/ATTACH]

I suspect you populated the whole board at once, and then switched on ... hoping it would work first time.

With a new project you should always populate the board in stages, testing each part as you go. You will now have a really difficult task debugging this, especially if you don't have access to an oscilloscope.

[chuubaba]

I tested it for first stage and it gave +5V so i was happy and today being a major festival holiday worldwide i decided to proceed as quick as i could. I have both multimeter and analog oscilloscope 20MHz. I tested each component prior to soldering. I share a better pic from right above to show what went where.

[chuubaba]

The holes there are for switch and i soldered the wire for the switch from bottom side of the board.

[Qiaozhi]

I tested it for first stage and gave 5V so i was happy and today being a major festival holiday worldwide i decided to proceed as quick as i could. I have both multimeter and analog oscilloscope 20MHz. I tested each component prior to soldering. I share a better pic from right above to show what went where.[ATTACH]43358[/ATTACH]

In that case you will need to debug the circuit logically, starting from the power supply, and then test each stage for correct operation. Please don't do what other newbies tend to do, and start randomly replacing components based on guesswork, or frantically resoldering every connection.

At the moment the fault could be anywhere, so check things in order:
1. Power supply.
2. TX oscillator.
3. Preamp.
4. Sample timing pulses.
5. Sampling integrator.
6. Second integrator.
7. Audio stage.

Somewhere along the line you'll spot the problem.
There's no point jumping straight to the audio stage if (for example) the TX oscillator is not working.

[kt315]

good example not use a layout from aliens and do selfmade layout.
we are been back to start to unright layout design point. the point why i had decided to do new layout, for help to all people.
but people do not want again to hear suggestions and want to fall into the same pit.
you can tell them not to do aliens' design, do only geotech design or can not - they will be left indifferent to your opinion.

[chuubaba]

would you please share with us the authentic SINGLE LAYER PCB DESIGN of GEOTECH BARACUDA !!

good example not use a layout from aliens and do selfmade layout.
we are been back to start to unright layout design point. the point why i had decided to do new layout, for help to all people.
but people do not want again to hear suggestions and want to fall into the same pit.
you can tell them not to do aliens' design, do only geotech design or can not - they will be left indifferent to your opinion.

[kt315]

i do not do geotech baracuda.
you must run in subforum geotech baracuda and seek there http://www.geotech1.com/forums/forum...otech-Baracuda

[chuubaba]

In that case you will need to debug the circuit logically........

I HAVE HIGHLIGHTED THE VALUE OF COMPONENTS FOR THE EXPERTS TO SEE IF THESE ARE CORRECT. MY DOMESTIC EXPERT HELP IS NO MORE AVAILABLE S I AM ALL ON MY OWN TO PROCEED. I WILL MOVE TO DEBUGGING (OR WHATEVER) AFTER THIS

[6666]

Why dont you just get a gerber file viewer and look at the gerber files

[chuubaba]

Why don't you look into this and advise. My domestic help used some alternatives for ICs TRANs and CAPs while other comps are as listed in BOM. Could this cause malfunction etc?

Why dont you just get a gerber file viewer and look at the gerber files

[kt315]

advise in what? i did this project from start to finish to help to all people having problems. you have to see my advise - my layout, my board, my schematic.

http://www.geotech1.com/forums/album...chmentid=41781

if you begin to built aliens' board you choice those problems again. we have to bound endlessly?

[Qiaozhi]

Why don't you look into this and advise. My domestic help used some alternatives for ICs TRANs and CAPs while other comps are as listed in BOM. Could this cause malfunction etc?

You cannot identify the problem by guesswork. Logical debugging is the only option.
Firstly, is this design based on the Geotech Baracuda, or some other alien version?
If it's not based on the Geotech Baracuda schematic, then there could be a whole host of other issues. Read the Build Document to understand the problems that exist with the original design, and then you'll see that you may even have components that have failed.

Start with the power supplies (+5V and -5V). Are these the correct voltage?

[chuubaba]

You cannot identify the problem by guesswork.----

I GOT THIS FROM THIS SITE. IT SAYS "REV 2" ON COPPER SIDE. MY HELP MADE THE PCB AND DRILLED etc IT

[Qiaozhi]

I GOT THIS FROM THIS SITE. IT SAYS "REV 2" ON COPPER SIDE. MY HELP MADE THE PCB AND DRILLED etc IT

In that case it probably contains all the original design errors. Can you post the schematic?
Also, have you measured the power supplies (+5V and -5V)?