Finished my HH1 (pics incl.) ! Some help needed

[emir506]

Hello friends,

My first HH1 is finished.
I post some pictures.Also pictures from scope for TP1,TP2,TP3 and TP4
Detector is detecting big things relative good, but coins are detected very poorly, ca 5-10 cm max.
I think I have made a mistake somewhere, specially TP2 doesn't look like Carl's pic.
If someone has any opinion about pics from the scope it would be very helpful for me.
Thank you.

[emir506]

Coil is 10 inch, 0.4 wire, 25 turns. Like in Carl's document. till now NOT shielded.

[Geo]

look if there are metalic objects down of the table
Also did you adjusted the sensitivity and delay ???

[emir506]

look if there are metalic objects down of the table
Also did you adjusted the sensitivity and delay ???

Ty Geo.
Maybe u right. I never tried it out of house
Sensitivity R35 , i tried some positions.

But I don't know what to do with R42,R45 and R46... Set them to the middle position.
What about picture of Fly back signal on TP2 . Is it with coil installed ? And without metal object near the coil ?

[Qiaozhi]

Ty Geo.
Maybe u right. I never tried it out of house
Sensitivity R35 , i tried some positions.

But I don't know what to do with R42,R45 and R46... Set them to the middle position.
What about picture of Fly back signal on TP2 . Is it with coil installed ? And without metal object near the coil ?

R42 sets the main sampling delay. At mid position it is probably set to around 40us. This will mean that it can detect large targets ok, but will detect smaller or low conductivity targets poorly. Also, set R35 to mid position, as it says in the article.