Delta Pulse

[porkluvr]

Thanks for reply..getting closer ..i am not a beginner and not an ender..used to do this more in the 80`s
building several radios and amplifiers with good sucess..no i am a pansjonist and have time to grooble..
But the rest of pcb component-overlay except stth placement you posted above, is it the same as this i have
you draw that placement now?
..i have all the pcb overlays from this forum..i think?

after schema stth is connected at 3 leg ??mysko that nobody know 100% where this pcb with stth diode..i see i will press it in place ..klogde it inn ..
Tanks..for help

----------------

i am a pansjonist and have time to grooble..

I don't know what you just said, but it sounds like fun.

after schema stth is connected at 3 leg ??mysko that nobody know 100% where this pcb with stth diode..i see i will press it in place ..klogde it inn ..

I'm not sure I know what you mean by "3 leg". You mean drain??

Yes, I only just now drew that placement modification - just so you can see how I might do that. I am not extremely familiar with the DP PCB layout so I can only hope that I did not make a mistake.

Sometimes it is not worth the time it takes just to make something look pretty. Better: be practical, and do whatever it takes. To "kludge" is OK if it works!

Just start with the basic plan and analyze each modification piece-by-piece. You'll get it!

[tuxnor]

work in progress
i will wait and make that mod in to this pcb..got dobbel up with components for delta pulse..so i look for a pcb with this place finied for stth. if not i must cut in board and place it .i rather wait and make another when a pcb lay with stth is posted,.i may get very old ?

[tuxnor]

I believe the 1N4001 might be the reverse battery protection diode VD7 and has nothing to do with the IRF740 drain circuit.

You should correlate your PCB parts placement with the schematic diagram. It looks like your schematic and the partial parts placement diagram you posted are for two DIFFERENT versions.

I am showing how I think you need to modify the PCB layout if you want to incorporate the STTH1210. It is not on the original PCB layout so that means you either need to change the layout or else 'kludge' the diode in.
I make no guarantee of accuracy but am trying to point you in the right direction

My picture does not address the 1 ohm resistor which I believe is missing from your PCB parts placement guide. You might need to make another change on the PCB to accomodate that resistor and the 4700uF connection!

It is up to you to correlate parts placement with the schematic if you intend to build this project. I don't think it is a beginners project, even more so if you choose to implement modifications that have not been designed into the PCB!

Thanks for reply..getting closer ..i am not a beginner and not an ender..used to do this more in the 80`s
building several radios and amplifiers with good sucess..no i am a pansjonist and have time to grooble..
But the rest of pcb component-overlay except stth placement you posted above, is it the same as this i have
you draw that placement now?
..i have all the pcb overlays from this forum..i think?

after schema stth is connected at 3 leg ??mysko that nobody know 100% where this pcb with stth diode..i see i will press it in place ..klogde it inn ..
Tanks..for help

[porkluvr]

Hmm,,is it 1n4001 ? they have added as substitute for stth ?or like this?

I believe the 1N4001 might be the reverse battery protection diode VD7 and has nothing to do with the IRF740 drain circuit.

You should correlate your PCB parts placement with the schematic diagram. It looks like your schematic and the partial parts placement diagram you posted are for two DIFFERENT versions.

I am showing how I think you need to modify the PCB layout if you want to incorporate the STTH1210. It is not on the original PCB layout so that means you either need to change the layout or else 'kludge' the diode in.
I make no guarantee of accuracy but am trying to point you in the right direction

My picture does not address the 1 ohm resistor which I believe is missing from your PCB parts placement guide. You might need to make another change on the PCB to accomodate that resistor and the 4700uF connection!

It is up to you to correlate parts placement with the schematic if you intend to build this project. I don't think it is a beginners project, even more so if you choose to implement modifications that have not been designed into the PCB!

[tuxnor]

No! You must realize that by using the IRF740 the circuit will usually have a peak voltage close to 400V. That would destroy the 1N4001 very quickly. You also have peak current somewhere around 2~3 amps depending on your pulse width and coil. That also eliminates other 1N4001 series devices. Don't be cheap, or else you will blow something up! Also, soft recovery is recommended in addition to being fast.

Digikey carries the STTH1210D diode for about $2.00 and they ship to most countries if I am not mistaken. This particular diode looks like a very good choice. There is nothing wrong with using a bigger diode than needed, so long as it can fit.

THANKS ..i will try to make it best as possible,,any cost lol I have my hand on STTH1210D where to put it.? and have they used 1n4001 as replacement for stth ?

[tuxnor]

1n4001

have they used this 1n4001 as a substitute for stth diode ??

http://v.youku.com/v_show/id_XMTIzNDA2NzMy.html

guess he have 2 gsm celluar phones also in the pocket and one 433mhz from office
faraday shield

[edtsr]

what could be the problem of my delta pulse, it only detects metal when it is very very close to the coil ( 23 turrns, #24 , 40 cm), IRF 740 does not get warm ( changed already but the same ) problems encountered during initial test, first broken connection between vD8 to vD9 and broken connection between P3 ( 20 K Pot) to R4 (5K6). TR2 is set 100Hz.

[che]

Thank you for your reply KTE15

if you press the knob RESET the sound would fall down in few seconds..

yes its true

the sound falls down to zero level, then you begin to turn THRESHOLD pot before a moment the sound will reveal again in staccato style. then you slightly turn it back before the sound must be dissapear to zero again.

I have taken this matter
but
When far from the hands of (RESET) hear the beep sound of a new

how i do run!

[apocalypto]

Battery problem

I wl'd to ask if this battery is better for DELTA PULSE and i wl'd to ask why i can test if my battery is ok or not (It decharge rapidly)
thank's

[porkluvr]

Hmm,,is it 1n4001 ? they have added as substitute for stth ?or like this?

No! You must realize that by using the IRF740 the circuit will usually have a peak voltage close to 400V. That would destroy the 1N4001 very quickly. You also have peak current somewhere around 2~3 amps depending on your pulse width and coil. That also eliminates other 1N4001 series devices. Don't be cheap, or else you will blow something up! Also, soft recovery is recommended in addition to being fast.

Digikey carries the STTH1210D diode for about $2.00 and they ship to most countries if I am not mistaken. This particular diode looks like a very good choice. There is nothing wrong with using a bigger diode than needed, so long as it can fit.

[tuxnor]

That is a more usual place for the FR diode (instead of being in parallel). I had an argument earlier in this thread where I tried to prove that adding an FR diode in series (as shown in your schematic) would improve the flyback time in the Deltapulse.

I don't recall having won that argument, but that would not stop me. I would still use a series diode because I believe you will see a faster time for your flyback voltage to decay to an acceptable level for sampling. I think that the optimum value of damping resistor will be different depending on whether or not you use the series diode. That will depend on your coil and would need to be determined experimentally.

On another note, just today I looked at what might happen if an FR diode were placed (in reverse) ACROSS the IRF740, and it does not look like a good idea because it does not seem to make the decay happen more quickly. Don't do that. Now, maybe if a MOSFET with an intrinsic FR diode were used it would be an improvement over a MOSFET with a standard zener, but that is a whole new ball game and I won't say another word about it. I have added too much confusion already.

Hmm,,is it 1n4001 ? they have added as substitute for stth ?or like this?

[porkluvr]

at last STT diode shown up ,,but 4700 uf c32

That is a more usual place for the FR diode (instead of being in parallel). I had an argument earlier in this thread where I tried to prove that adding an FR diode in series (as shown in your schematic) would improve the flyback time in the Deltapulse.

I don't recall having won that argument, but that would not stop me. I would still use a series diode because I believe you will see a faster time for your flyback voltage to decay to an acceptable level for sampling. I think that the optimum value of damping resistor will be different depending on whether or not you use the series diode. That will depend on your coil and would need to be determined experimentally.

On another note, just today I looked at what might happen if an FR diode were placed (in reverse) ACROSS the IRF740, and it does not look like a good idea because it does not seem to make the decay happen more quickly. Don't do that. Now, maybe if a MOSFET with an intrinsic FR diode were used it would be an improvement over a MOSFET with a standard zener, but that is a whole new ball game and I won't say another word about it. I have added too much confusion already.

[kt315]

my delta pulse emit a continued sound, when I press the RESET the sound fall down but after 5 seconds it apear again (a continus sound). what the problem?

in reality delta pulse does not need in RESET knob. sound must fall down yourself, but more longer in time. IMO it has SAT autotuning... RESET knob is only sorta an help to decrease long time of SAT tuning, to do not waste a time on the tuning.

[tuxnor]

youre right

I'm glad I asked but I'm still a little bit confused.

Maybe the FR diode is not meant to replace the IRF740 but is suggested to be placed across the IRF740 to help reduce the flyback time?
Just a guess.

Think about it - you simply cannot replace the IRF740 with a diode. No how, no way. Or, at least I don't think so. But, putting a FR diode (in reverse) in parallel from source to drain would help reduce flyback time. IRF740 already has a reverse connected diode from S to D. Adding an FR diode would speed things up a little bit.

Even better might be to use a MOSFET that already has FR diode. I know of only one such MOSFET at this time, but I am sure there must be others.
I found this only by accident:

STF12NM50ND has FR diode: http://www.st.com/stonline/products/...e/ds/14936.pdf

STF12NM50N has a slower diode but is, apparently, otherwise identical:

http://www.st.com/stonline/products/literature/ds/11384/stf12nm50n.pdf

I am interested in the FR diode version but unfortunately the TO220 package is not stocked by my favorite distributer, only Dpak or DDpak are stocked. I will search some more when I get time, or maybe try the DDpak in my project (if it ever gets to that stage of completion).

Without having the exact diagram to go along with the parts list you posted I don't know where two of the 4700uF capacitors go. I can only find one 4700uF on my DP schematic. Maybe they are all supposed to be in parallel, which would provide 3x the filtering; a very good idea.

++++++++++++++++++++++++++++++++

Here is a link to the STTH1210D. http://www.st.com/stonline/products/...4/stth1210.pdf

tuxnor, what you are probably wanting to do is stick to the original DP schematic but add one FR diode across the IRF740, and add two 4700uf capacitors across the one that's already there. (?!) Be sure and connect the FR diode in reverse, or else it will muck things up and won't last very long.

THANKS..youre all right ..not a replacement for irf740 and i also found schema at last

[tuxnor]

at last

at last STT diode shown up ,,but 4700 uf c32