Analysis this schematic

[porkluvr]

Why don't you show us the work you have done on your PCB. Show us the front and back of the PCB, up close, but not so close that pictures are out-of-focus.

edit: Oh, and you say that the U4-6 signal is bad? Well, why don't you show us?
No movies, please... in-focus photos good, out-of-focus movies bad.

Show us how you have installed the compensation capacitor.

[mohandes]

find why dont have good detection, gurus what is your idea

mr georgi and gurus Hi
today i go collage for adjustment but pin6 ne5534 is very bad.(i first nulling and then adjust pin6 on 0volts)
So i am going to use lf357?if i use that should be change pin5 and 8 together.
or i change resistor that parallel with coil and change it on 330ohm.(now it is 220 ohm)
which is better,guide me please i finish it buet dont know what i do?


EDIT (this is for gerorgi):you put my post in#95 but i should say you that time Tsecond 4538 not work .

[Davor]

Georgi or someone with recent experience with tuning this rig will be able to help.

[mohandes]

You seem to have forgot the part where I said that the scope must be set on DC coupling or else DC information will be lost.

But, you have totally misunderstood what I wanted to see. You twisted my words, yet again.

HI

all guru thanks but need finall help

I found small matter but very important.

I FINISH MY DETECTOR AND FIND PROBLEM(better say not problem)
when i connect batterys and have 17 - 13 volts i can adjust all.but when it go down the 13v can not adjustment.

i put TP3=0v
TP5=1.5v(i can adjust it by delay and RV9)[it is hard to me for adjust to 0.6or0.8v){i put delay on 50or100mks, ithink 50mks better}
TP4=0v(discrimination)

and it detector coin(diameter=2.2cm)in air at 10cm and but green led is on?/(maybe true)
AND speaker always tic-tic that can be change by tune volum and when find anything the sound stop, is it true?

[mohandes]

hi all
it is important question for me.
when i adjust the pin6 ne 5534 on -0.2volts,i cannot adjust TP points(TP3=-5.83 and TP5=7.7volts and arenot change)

tomorrow i measure again

Please interduce me sites for find equivalent for Ics and Trs

[porkluvr]

hi davor i think mr porkluvr want that(or i dont understand that)
thanks for attention
mr porkluvr says :one of the scope set on 500Us an one of them on 50Us , so digital scope on 500Us and analog on 50Us

but my problem is that
when i connect c13 can not set pin6 ne5534 on -0,2v ,i check all and true.

WHat happen?

You seem to have forgot the part where I said that the scope must be set on DC coupling or else DC information will be lost.

But, you have totally misunderstood what I wanted to see. You twisted my words, yet again.

[Davor]

Could it be possible that the capacitor is somehow broken?

[mohandes]

hi davor i think mr porkluvr want that(or i dont understand that)
thanks for attention
mr porkluvr says :one of the scope set on 500Us an one of them on 50Us , so digital scope on 500Us and analog on 50Us

but my problem is that
when i connect c13 can not set pin6 ne5534 on -0,2v ,i check all and true.

WHat happen?

[Davor]

You'll learn much more when you use 2 channels simultaneously. All your measurements are single channel, and it will be great if you can see at least the 555 output for time reference. Also you can use 555 output to sync your measurements.

Right now it looks good, and I see you use batteries.

[mohandes]

Hi all
i come back, first i say dont laughing to my speaking.
see this videos:

http://www.uplooder.net/cgi-bin/dl.cgi?key=a9d55ec469e02ce59e89edfd0c330cb1

and the next video i speak Farsi with English together ,sorry me

http://www.uplooder.net/cgi-bin/dl.cgi?key=a42e1adac5dcd1ddfb64dbf39353b5a3

ok see them,again sorry me i forgot should speak just english

[mohandes]

yeay team let's go home

edit: That's so bad it's scary.

Yeah lets go(!!!!!!!!!!!!!!!)
my friend i will change my supply and add C13(10pf){pin1,pin5}

any think remind for me?if you have it tell me complete

and you think if i change them my input in U5 ar correct(Sa<Sb<Sc)

so thanks

[porkluvr]

yeay team let's go home

edit: That's so bad it's scary.

[georgi.g.zhelev]

FOR ALLS : SHEMATIC IS CORRECT! NE 5534 .... pin 6 : See # 95 PHOTO 2 , waveform is correct !

FOR FINAL TEST : Powered only by battery (accumulator), NO FROM THE LAB. POWER SUPLY ! ( 50 Hz )

[mohandes]

Don't panic, I think I found the problem. Alex's schematic and the PCB left out the 10pF compensation capacitor C13 between pins 5 and 1. Mohandes, get you a small 10pF ceramic disk, find a way to kludge it into the circuit, and then you can probably move forward.

Georgi, I'm sorry I 'blew you off' when you mentioned that the preamp signal looked wrong. I was looking at a different signal that I thought was U4-6, and I saw nothing wrong.

edit: Georgi's schematic shows C13 between 5 and 1, not 5 and 7 like I originally stated.

re-edits: (yeah, this is a mess.) I may be re-editing this post until my time expires.

The NE5534 datasheet shows that compensation should be applied between pins 5 and 8, but go ahead and see what happens by going between 5 and 1. Maybe that is a mistake in the original schematic - maybe or maybe not.

please read it

http://www.geotech1.com/forums/showthread.php?10894-Bulgarian-PULSE-STAR-(-close-to-Legendary-one)/page20

#478 my means
disagree

[porkluvr]

Don't panic, I think I found the problem. Alex's schematic and the PCB left out the 10pF compensation capacitor C13 between pins 5 and 1. Mohandes, get you a small 10pF ceramic disk, find a way to kludge it into the circuit, and then you can probably move forward.

Georgi, I'm sorry I 'blew you off' when you mentioned that the preamp signal looked wrong. I was looking at a different signal that I thought was U4-6, and I saw nothing wrong.

edit: Georgi's schematic shows C13 between 5 and 1, not 5 and 7 like I originally stated.

re-edits: (yeah, this is a mess.) I may be re-editing this post until my time expires.

The NE5534 datasheet shows that compensation should be applied between pins 5 and 8, but go ahead and see what happens by going between 5 and 1. Maybe that is a mistake in the original schematic - maybe or maybe not.