Delta Pulse

[kt315]

Do not really know what it's called this circuit but this is what he does.

i call this circuit first protect stage against an overloading. IMO this is too closer to stage function.

Are T2 & T3 for automatic delay control of ?

not. they begin to work (to turn on) ONLY on pretty big target you move a coil on.

yours

[Jose]

Hello Grat_Alex
Do not really know what it's called this circuit but this is what he does.
Suppose you adjust the delay of 20 usec, then approached a metal coil, the delay runs automatically to 25 usec. This is by action of T3 and T2 on the DELAY circuit (pin 2, 453. It can be observed with the oscilloscope.
If we use small coils of fast driving, this circuit can be disabled by opening the collector (C) T2 or T3 for a smoother adjustment of time delay and in some cases stability, also helps increase the value of R6.
Again, this is valid to use small coils (20 to 28 cm) of rapid delayed, home of small objects.
If you use large coils and will not detect the ceramics, I should not make these changes.
I particularly prefer to use a potentiometer in the delay that use coils of different sizes.
Concerning this last paragraph, I think that you mentioned is what the original circuit, I'm sorry I can not add anything else.
regards

[Great_Alex]

Hi jose

Are T2 & T3 for automatic delay control of ? I already think they are for high voltage shock and absorb extra amount of fly back voltage

about the Delay : i found it's not so useful for ignore hotrocks and viscose magnetized objects like ancient bricks ! i prefer to use a fast response i use 2k resistor as p1

I want to have reverse signal on vco it means when a metal approach to coil the sound decrease ! and when take it away the sound increase ?

best regards
Alex

[Jose]

Hello Great_Alex
I agree with the slow response to deep targets, in automatic mode.
The controls can be set in my humble opinion are:
RANGE: Replace R 250K P2 fixed. 1.5 nF C6 substituted by 1 nf, tended a sample of 250 usec or so, I think is enough.
TX POWER: internal preset adjusted from 125 to 150 usec. (I got the best results)
DELAY: I think it can not be replaced, you can expand the range to use coils C4 changing fast response of 1.5 nf nf 1, R7 changed to 10k 15k
SENS and THRESOLD: I should keep them as they are.
You may experience disabling the automatic control of "Delay" (T2, T3) and increase the value of R6, 1K (1.5 to 2.2K) for more stability in some cases, lower turns coils.
These experiments can improve or worsen the performance of the MD, according to the particular circumstances of each case, the risk borne by the operator.
Best Regards
Jose

[Great_Alex]

auto tracking is very good facilities , with auto track you search in mineral soil and diffrent type of soil very silent and better depth.
but very fast auto track , reduce the detector response on deep target


deep targets have long signal length and increase signal more slowly than shallow targets
and fast auto track mask the target.

another important fact for delta pulse is :
the delta pulse has many setting and in field work the detector should be have the least adjusting setting cause it make the operator confused

i want to reduce the number of parameters and change them for my reasion - Finding big and deep metal with 1m*1m coil- not coins with 30cm coil

did anyone has idea about changing the Power - Disc - Range - Sens ... with constant resistor for this situation

i think we can do this for all knobs but sens need to be variable

[Jose]

Hi Great_Alex
Thanks for this Mod
In the original project, the audio fade when the coil remains stationary on a detected object.
This improves the work of MD in mineralized soil? What is your opinion.
Meet some mod to increase profit?
regards
Jose

[Great_Alex]

Change tune place

this zero button Switch works well now

Arash : Delta is good and stable if you good tune it but not as ps2 performance

[Arash]

Hi Hamid

Delta pulse is best BARA GHAZ CHARANDAN
BE DARDE LANAT KARDAN HAM NEMIKHORE
VAGHTETO TALAF NAKON

AGE DONBALE GANJI BORO YEK GPR BEKHAR

[hamidloucif]

broblem with my detector delta pulse

I board a problem with my detector it detects air dan 10cm I inform you that I board eseyes undiquer all changes on the forum if Geotech for ca I ask your help if posible (email) [email protected] - receverz blown up my best t

[Great_Alex]

Hola jose

nada útil se encuentra en la página n º 37?!
pero gracias de todos modos


I disconnect T7 B and C legs

the result is amazing :
reset works amazing it's works realy like Reset now!
speed of autotracking reduced and it can detect deep in auto mode

[Jose]

Hola Betobrambi
No hay que agregar nada de los componentes ya existentes en su PCB, solamente hay que controlar.
Suguiero controlar la salida del 555 (pata 3) y el control de volumen, por ser elementos que corresponden a la etapa de sonido.

No need to add anything to the existing components on the PCB, but must be controlled.
Suggest a package to control the release of 555 (leg 3) and volume control are elements that correspond to the sound stage.
Jose

[betobrambi]

Hola José, te va la imagen

corrigeme si estoy equivocado, por favor... puedes dirigirte a mi persona en el siguiente email: [email protected]

gracias y mañana informo resultados

Great Alex and Jose

This is the position that takes NE 555 in the circuit, I suppose that I must weld a cable of Output 3 with a potentiometer of 100 ohms to one of the legs of the volume.
He is correct this?
I am going to try to draw it in the scheme of
components. to correct if I am mistaken.

they flow I inform broken results on diodes or resistance

for your help me, thanks my friends

Heriberto

[Jose]

Hello Grat_Alex
Experimenting with different values of C21 get: Quick Response with less capacity but unstable.
Slow response with increased capacity, but always with the same sensitivity once stabilized.
Damping resistance, Coil decompensated or poorly detector setting, you can create erratic operation of "automatic mode."
Regards Jose

[Great_Alex]

Hi Jose

changing R27 or C21 changes the auto tracking time but it change the metal detector max depth according by my tests .

i think the soloution must be at T7 (Maybe)


Mr Betobrambi

I don't know what kind of multi meter you have
first you check a diode in out of circuit to find how to work with your multimeter.
the diode must have some resistance in one way and no current in another way
when it short curcuit and the multimeter beep i think you should change it

please tell the diode no according the schematics and it's response

[Jose]

Hello Betobrambi
The volume control knob is the last right, according to the picture of the PCB.
The value is 100 ohm, not 1K as I said before. I apologize.
You may 1N4148 diodes are shorted by what you told us.
Out of respect for members of the forum, I do not want to write in Castilian.
You can send me a private message Castilian if you wish, and try to help within my means.
José