Bulgarian 'PULSE STAR' (... close to Legendary one)

[Geo]

LF357 has double bandwidth (20mhz) from 5534 (10 mhz). I don't think that has something to do with the off set voltage.

[georgi.g.zhelev]

georgi.g.zhelev

What is the advantage of useing a LF 357 or OP 27 over a 5534 in this circuit ?
has it something to do with the off set voltage ?

WHAT IS IMPORTANT TO IC U4(NE 5534, receiver)? 1. HIGH SLEW RATE ; 2 OFSET DRIFT ("0" ofs. drift); 3..LOW NOICE ; Frequency is not important, PI works f = 100 ... 500hz!
NE 5534> high slew rate = 13V/mikr.sec.; OP27> high slew rate=11V/micr. sec. OPA 2132> high slew rate=20V/micr. sec ; LF 357> high slew rate=50V/micr. sec !!!
NE 5534> ofset drift =5micr.V/*C ; LF357 > ofset drift =5micr.V/*C ; OPA 2132 > ofset drift =2micr.V/*C OP27> ofset drift =0,2micr.V/*C !!!

[georgi.g.zhelev]

How i can work the PS-G as all metal??? RV5 is a trimmer.

RV5 is trimmer ,setting and not touch more ! Mode all metal is channel audio , speaker > 16ohm ,sound : tic-tic-tic -tic-tic-tic-tic.ОК?

[Geo]

RV5 is trimmer ,setting and not touch more ! Mode all metal is channel audio , speaker > 16ohm ,sound : tic-tic-tic -tic-tic-tic-tic.ОК?

Thanks georgi.
Finally i replaced the coil and dumber resistance and now the Tx pulse is 550V. For the moment it's OK. With high pulse and voltage at pin6 of 5534=-0.2V i adjusted good the RV7 and RV8 for zero out at TP3. Now i see that the discrimination is good but i still have some problems. Bad sensitivity at audio channel and bad stability. Every time that i pass a metal near to coil i must press the zero button because one led remains light, and the sensitivity is more low.
Slowly... slowly it will work.

Regards

[pigeon]

hi ALL

somebody that the PCB of pulse star-BG, please.


thank you

best time

P.

[georgi.g.zhelev]

PS-G

Bad sensitivity at audio channel and bad stability(Geo) . RV3 >potenciometer .."DELAY" ,looking for sensitivity and stability, good discrimination. IC 8a, trimer RV9 setting sensitiviti to audio channel (0,6....0,8 v to pin 1); R35 (U= 1,5M. R30,R32 =1,5M

[Geo]

Bad sensitivity at audio channel and bad stability(Geo) . RV3 >potenciometer .."DELAY" ,looking for sensitivity and stability, good discrimination. IC 8a, trimer RV9 setting sensitiviti to audio channel (0,6....0,8 v to pin 1); R35 (U= 1,5M. R30,R32 =1,5M

All these are OK. Audio sensitivity now is OK. Sensitivity to metals are medium (one euro at 20 cm). But i don't hear (tik tik tik...), only when i hold push the buton then i hear the tik tik tik...
When i receive a metal from short distance it detunes and i must press the zero buton again. Why?????. From what i saw is returning a signal from U11b to U10b, but i can't explain it. I replaced the 4066 but no results. For the time this is the bigest problem!!!!.
btw... who is the disadvantage of ligh version??

Regards

[georgi.g.zhelev]

When i receive a metal from short distance it detunes and i must press the zero buton again. Why?????(Geo) System is overloaded !!Chesc IC Ua,Ub,Uc,Ud (IC 4066),Press the button, SEE : Se, Sd (pin 5,6 pin 12,13 to 4066 : - > + ; +> - OK?

[Geo]

When i receive a metal from short distance it detunes and i must press the zero buton again. Why?????(Geo) System is overloaded !!Chesc IC Ua,Ub,Uc,Ud (IC 4066),Press the button, SEE : Se, Sd (pin 5,6 pin 12,13 to 4066 : - > + ; +> - OK?

Hi georgi.
I checked the 4066 and it is ok. Also i replaced it . When i press the buton is ok, but every time who i get a strong signal i must press the buton?????
Is it normal????
If it is normal then i finished the PS-G.

Regards

[maikl]

Hi georgi.
When i press the buton is ok, but every time who i get a strong signal i must press the buton?????
Is it normal????
Regards

Yes it is normal, when the metal is large or too close, because it leads to overloading...
Best regards.

[georgi.g.zhelev]

PS-G

When i press the buton is ok, but every time who i get a strong signal i must press the buton?????
Is it normal???? YES,this is normal, PI detector to search for small signals.

[Geo]

Thanks
Can you tell me who is the disadvantage of ligh version??
Also why OP37 is not good for this detector??? It has very hight bandwidth and slew rate.
btw... the 50us pulse at ne5534 (curve 5Ud21,,,d24) are similar to a 20khz signal so we need a bandwidth more than 40 Mhz for a gain of 2000.

Regards

[georgi.g.zhelev]

Hi georgi.

Geo :If it is normal then i finished the PS-G
.

Regards

Мy result for PULS STAR-G : L diam. 30cm ; R= 0.7ohm induct.= 400mikr.H 1 EUR , AIR TEST ..=. 30cm : discrim ..(mikroampermetr)= 24cm ; GRОUND EFFECT > ZERO ! ;

[Geo]

Мy result for PULS STAR-G : L diam. 30cm ; R= 0.7ohm induct.= 400mikr.H 1 EUR , AIR TEST ..=. 30cm : discrim ..(mikroampermetr)= 24cm ; GRОUND EFFECT > ZERO ! ;

What you mean "GRОUND EFFECT > ZERO" ??

[georgi.g.zhelev]

"1. GRОUND EFFECT > ZERO" ?? Land does not affect !
2. Can you tell me who is the disadvantage of ligh version?? ..No analogue memory.I have not worked!
3. Also why OP37 is not good for this detector??? It has very hight bandwidth and slew rate.
btw... the 50us pulse at ne5534 (curve 5Ud21,,,d24) are similar to a 20khz signal so we need a bandwidth more than 40 Mhz for a gain of 2000. ... I TESTED,does not work well !! BEST IC (U4)...OPA 2132 ,LF357,OP27. (NO NE 5534)