Practical tested

[scs-bg]

Very good reduction in ground effect is achieved by using DD coil. The receiver bobbin used is common and for both the channels. This is what I tried 15 years ago in a hybrid detector. The practical results are very good. The coils on the receiver and transmitter should have the same inductance. If this is not the case, false positives will be obtained in the motion.

[Op04]

Will you share the schematic? Thank you Sir

[scs-bg]

What I wrote is enough for a good designer to create a well-functioning detector. For me it is a hobby, but many people profit from my schemes. I have a scheme but I will not publish it.

[scs-bg]

You haven't thought about why the best manufacturers in the world don't produce hybrid detectors???

[Detectorist#1]

Hi scs-bg,
The idea for ground balanced PI metal detector with two equal RX coils is very very old. The DD coil is only one variant if this idea. An other variant is OO search coil (very similar to DD coil but with less overlapping) . Also the super DD coil with differential connection of the two RX coils is the third variant. What variant have to be used depend of the real ground condition. If these conditions are different in close distance - only DD coil is capable to reach good ground eliminating. Nothing new under the sun!
BTW, it is interesting what type of MD you will understand as "Hybrid" type.

[scs-bg]

I did not discover America, Columbus or Leif Erickson Vikings did it a long time ago. I am sharing a real experience. Or maybe this is my mistake....

[scs-bg]

All projects on this forum related to discrimination start from the idea in this old scheme of mine. This is a long time before project Voodoo.2011. You will do better if you don't teach me.This is not right address.

[scs-bg]

I'm an adult now and I don't want to waste my time arguing with people who think they know everything.

[Detectorist#1]

Hi sascho from Varna,
Plese read this:
https://www.geotech1.com/forums/foru...detector/page4
post #57
Here I mentioned that the first idea for use of IB coil for more good discriminating in PI detectors and reading the RX signal on TX-ON time is from Sascho from Bulgaria from year 2008. Some people not understand how this idea works and I explained how this idea works later in this discussion in #62. But my question rest - what type of detector have to be named "Hybrid"?

[Detectorist#1]

Is the reading of RX signals during TX-ON time instead of during of TX-OFF time is enough to put the name of MD to be "hybrid"?

[scs-bg]

Dear friend, these are pointless arguments. The Chinese rightly say that it doesn't matter what color the cat is. It matters whether it catches mice. In short, what matters is what you have done. I have done a lot. Unfortunately, without any benefit for me personally. I have not earned even a single euro from it.

[Detectorist#1]

Sorry Sascho, but after your post for Surf PI with TIP32 transistor, I decided that you are very young and you just start to made PI detectors.

[scs-bg]

I have many well-working original circuits. Unfortunately, they are of no use to me. I work in industrial electronics and I don't have time to make money from what I invented for pleasure. I didn't have time for patents. Maybe all this will die with me.

[Detectorist#1]

You are not right. Your benefit is the the pleasure to be author of some new ideas! This pleasure haven't to be measured in Euro.

[scs-bg]

I'm not angry about transistor type 32, you're right. The mistake is trivial, but it's mine.