Volksturm SM + GEB

[mehdi]

Hi dear don and thanks for your fast reply
when i connect 12v battery, it sound but not any respond to metals but ehen i play with variable resistors, it can detect .5*.5meter AL metal at about 10cm!!
i hav not oscop but i have DMM. i hope you can help me
thanks
mehdi

[dfbowers]

Hi don
i today finished my volksturm sm+geb and test it, it seem that work, but it dont any reflex and answer to metals! can you help me please?
mehdi

Sure, I can help. Could you please be more specific to what your problem is? You say that it "works". In what manner?

I'm not sure how the word "reflex" translates.

If your circuit is built correctly, then I would expect that we should have to work on tuning and phasing. I have built 3 of them, all have worked but I needed to tune the coils to get the detector to respond correctly.

Do you have an oscilloscope? If not, we may be able to figure it out with a DVM, but it will be more difficult.

[mehdi]

Hi don
i today finished my volksturm sm+geb and test it, it seem that work, but it dont any reflex and answer to metals! can you help me please?
mehdi

[dfbowers]

I like this project.

I tried to make this detector a long time ago, but didn't have the right schematic. Could you explain your coil dimensions?

Thanks in advance.

Sure..

See post # 121


http://www.geotech1.com/forums/showt...t=14595&page=5

[kuraja]

I like this project.

I tried to make this detector a long time ago, but didn't have the right schematic. Could you explain your coil dimensions?

Thanks in advance.

[dfbowers]

volksturm power consumption is around 30 mA. Also, I'm no expert but back to back polarized caps at twice the value should be an ok replacement for bipolar caps. At least that is the way that they use then in the TGSL project.

I hope that you get your project running! Getting your coil phasing right will be your next challenge. I just tuned to resonance and it works fine.

[mehdi]

Hi Don
thanks I'm nearly finish the project, i am making coil yet and when finish i will test it.
i hope it work fine...
regards
mehdi

[kuraja]

What is the device's consumption?

Best Regards

[dfbowers]

Hi Don
thanks but i cant find 2.2uf 16 or 25v! so can i use two 4.7uf 16v in series connect with neghativ legs so it will be about 2.3uf 16v and bi-polar? what is your opinion ?
regards
mehdi

Using a 2.2uf cap rated for 16v should not be a probem at all. 16v is probably 3 times more than what the capacitor will ever see anyway.

[mehdi]

Hi Don
thanks but i cant find 2.2uf 16 or 25v! so can i use two 4.7uf 16v in series connect with neghativ legs so it will be about 2.3uf 16v and bi-polar? what is your opinion ?
regards
mehdi

[dfbowers]

Hi don
above shematic is volksturm S, and 225k 400v is: 2.2uf 400volt c4 in volksturm sm+geb shematic
regards
mehdi

C4 should be bi-polar. 400v seems like overkill. Maybe 16 or 25v?

[mehdi]

Hi don
above shematic is volksturm S, and 225k 400v is: 2.2uf 400volt c4 in volksturm sm+geb shematic
regards
mehdi

[dfbowers]

Hi don how are you?
don, can i use a headphone instead buzer?
and c4 is 2.2uf bi-polar? true? i can find 225k 400v ; can i use that? or maybe the voltage of cap is high?
with many thanks
mehdi

I do not use a buzer, just a set of headphones and it works just fine.

I think that C4 is supposed to be 1.0 uF, according to the schematic above, right?

What is 225k 400v?

Don

[mehdi]

Hi don how are you?
don, can i use a headphone instead buzer?
and c4 is 2.2uf bi-polar? true? i can find 225k 400v ; can i use that? or maybe the voltage of cap is high?
with many thanks
mehdi

[cristi71]

TY