Does anyone know how to make a pinpointer?

[azigta]

LOL! minimax is russian one.

I have no idea about this things I heard the word pin pointer for the first time about a week ago... xDD But do you have a post in which you explain how you made it? That might help xD Thanks

[kt315]

look here i had uploaded all PP infos all-eggs-in-one-basket
http://www.geotech1.com/forums/showt...ive-here/page4
post N95

[azigta]

look here i had uploaded all PP infos all-eggs-in-one-basket
http://www.geotech1.com/forums/showt...ive-here/page4
post N95

Great, downloading. Thanks!

edit: wow o.o I'm sure I will build one of them. What a great information. Awesome, thanks!

[azigta]

look here i had uploaded all PP infos all-eggs-in-one-basket
http://www.geotech1.com/forums/showt...ive-here/page4
post N95

I think I'm going to make the minimax pp II , the smd components are 0805?

[silverdog]

yes 0805, I made one some time ago https://www.youtube.com/watch?v=zq1JTMJmFjQ
very small pcb 36 x 17mm, need good eyes or magnifying lamp
probably have some pcbs somewhere

[woodbob123]

I only put the details of the components I used, away from home for a month, nothing seemed critical transistors I used were just what I had in spares box. Any npn or pnp should work fine the coil was wound as in the post. Oscilator was on a vero board strip along with the diode and smoothing caps, rest of components on a second board. Layout is not important just keep the leads from coil to oscilator short. If needed will post pictures when I get back home.

[kt315]

0805, but better size is 1206 (more popular in DIY environment). 0805 is easily setted
on 1206 place also.

[Koala]

yes 0805, I made one some time ago https://www.youtube.com/watch?v=zq1JTMJmFjQ
very small pcb 36 x 17mm, need good eyes or magnifying lamp
probably have some pcbs somewhere

Looks to have good distance but does it work in static mode. In the video it looks like the coin has to be in motion

[KingJL]

yes 0805, I made one some time ago https://www.youtube.com/watch?v=zq1JTMJmFjQ
very small pcb 36 x 17mm, need good eyes or magnifying lamp
probably have some pcbs somewhere

Siverdog, If you happen to trip over any of those pcb's, I would be interesred in one.

[azigta]

I'll try to make the pcb at home, It's been a long time since I last made a pcb but I think I'll be able to make it, If not, I may buy it if silverdog has it.

By the way, I savaged a 10mm diameter 122mm long ferrite rod, could I use it for this project? The second coil in the minimax pdf says that 400turns of 0.35mm on a 10mm diameter 80mm long rod it's enough to detect a coin from 7cm. I was planning to use 0.4mm cable as when I finish making the search coil for the barracuda I will have about 8 meters of it left (hopefully if everything goes right). But I have never winded anything so I don't know how the longitude of the ferrite rod affects in the turns "equation". Do I have to wind all over the rod? or just using a part of it? Do I wind it directly on the rod or do I have to use a small reel like in the pictures . If so, how long do I have to make that reel? Wow so many questions. I'm sorry

Also, there's a 33uH coil in the schematic (L2), can I wind that coil in the same ferrite rod? If so, where do I wind it? Maybe each coil on each of the rod's side? or one on top of the other? I don't see that coil in the pictures.

I may buy a cheap coil meter so I can test how many turns do I have to give it to make it 33uH

[azigta]

I only put the details of the components I used, away from home for a month, nothing seemed critical transistors I used were just what I had in spares box. Any npn or pnp should work fine the coil was wound as in the post. Oscilator was on a vero board strip along with the diode and smoothing caps, rest of components on a second board. Layout is not important just keep the leads from coil to oscilator short. If needed will post pictures when I get back home.

Thanks, I didn't know any npn or pnp would work, But I'll try to buy the ones listed on the schematic. Though, if you got it working with other transistors/parts, a component list would be appreciated. Also it would be nice to see pictures when you can post them, Thanks

[willy]

Teemo, a forum member, sells a kit http://www.digiwood.ee/8-electronic-projects/2-metal-detector-circuit

[azigta]

Teemo, a forum member, sells a kit http://www.digiwood.ee/8-electronic-projects/2-metal-detector-circuit

Thanks, I'll add it to my list, For now I think I'm going to make the minimax

[azigta]

Well, I have bought an lcr meter so I can solve all the coil measuring problems, It won't arrive until March (ships from Japan) but it's a good one. It's a Der EE DE-5000

[KingJL]

Hybrid MiniMax/chemelec

I was playing around with the MiniMax in LTspice and decided to re-configure the minimax and use some of Gary's (chemelec) pinpointer and came up with this. The LTspice run looks very good. Now all I have to do, is breadboard it up and test in the real world. I have to wait until I receive some ferrite cores to wind the 2 mH inductor. This thing appears to be very sensitive for a pinpointer.

hybrid.pdf