Announcement

Collapse
No announcement yet.

SM PRO 3

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
  • #1

    SM PRO 3

    I am still waiting for my soldering iron to come in and had a little time to mess with my SM PRO 3 again. So I wound a 4" coil .51 solid copper 38.5 turns 305 mH to try and see what range of detection it would get over the other coils I had made. but it would only detect a nickel and quarter at maybe 6" and if I passed the coin closer to the coil 2.5" or closer I get a sound just like putting voltage to a speaker no beep like before. I tried the other coils I have and the same thing. It also seems like the volume is not as loud.

    Can someone point me in the direction as where to start looking and what I need to start checking. I have a multi meter / capacitance / inductance meter but I do not have a oscilloscope yet.


    Thanks for any help.
    Last edited by Darin; 04-27-2015, 02:27 AM. Reason: left something out
    Tags: None
  • #2
    you can use the card son of pc as osciloscope but the max range is 20 khz

    Comment

    • #3
      Checking my SM Pro 3 tonight I noticed the voltage at pin 4 on NE5534 kept changing. I would adjust R 10 back to 0 volts and check resistance at R2 and it was jumping around never would settle down.
      Went back to NE5534 pin 4 and the voltage had went back up, varying from +.2 to +1.4 at different times I would go back to adjust it.
      I disconnected power to the board took a break for a few minutes went back, looked at the schematic then connected the power, no sound in the head phones and the voltage at NE5534 pin 4 is at +4.6 and adjusting R10 does not change it.

      What is going on with my detector ?

      Comment

      • #4
        Originally posted by Darin View Post
        Checking my SM Pro 3 tonight I noticed the voltage at pin 4 on NE5534 kept changing. I would adjust R 10 back to 0 volts and check resistance at R2 and it was jumping around never would settle down.
        Went back to NE5534 pin 4 and the voltage had went back up, varying from +.2 to +1.4 at different times I would go back to adjust it.
        I disconnected power to the board took a break for a few minutes went back, looked at the schematic then connected the power, no sound in the head phones and the voltage at NE5534 pin 4 is at +4.6 and adjusting R10 does not change it.

        What is going on with my detector ?

        Sorry i should have pin 6 on NE5534 not pin 4

        Comment

        Previous template Next
        Working...
        X