Need help Gary metal detector

[yhl]

Hello my friend

I can replace the potentiometer R5, change the resistance value changes in pulse power
As the current is normal. I think the low detection range is the pulse power is low.
Will the big impulse resistor values R5, or small impulse?

[Qiaozhi]

I can replace the potentiometer R5, change the resistance value changes in pulse power
As the current is normal. I think the low detection range is the pulse power is low.
Will the big impulse resistor values R5, or small impulse?

yhl - I cannot understand your reply.
Does the current consumption of the circuit change when you adjust the pulse width pot?

[yhl]

你好

你好乔治你。我只能用中文说清我的意思，我做的是加里脉冲1电路。R5的是脉冲宽度调整。我原来是用了一个 15K的的电阻。我现在想用电位器调整，我只是问下电位器电阻值大的是时候是脉冲大，还是电阻小的时候脉冲 大？

[yhl]

nihao

我想问下一个？ 加里脉冲1电路。 IC5 IC6的IC8 IC7的。 可以NE555呢？ 或ICM7555。
NE555会影响与它的脉冲电源？

[yhl]

help

Dear friend. I made a new circuit board Gary pulse 1, with the new parts. Do very well.
But also that the original circuit board is the same problem. The total current 70 mA.
4-inch test 2.5CM coins, cans 8 inches.'s Largest iron 50CM. What is the reason for the request?
My coil is 0.51MM, 26 laps, 8 inches in diameter.

[maikl]

Dear friend. I made a new circuit board Gary pulse 1, with the new parts. Do very well.
But also that the original circuit board is the same problem. The total current 70 mA.
4-inch test 2.5CM coins, cans 8 inches.'s Largest iron 50CM. What is the reason for the request?
My coil is 0.51MM, 26 laps, 8 inches in diameter.

Hi yhl. To ready a PI detector requires a little knowledge. It's not enough just to braze the elements of the PCB. You need the oscilloscope and knowing what to do with it. Is not enough to change the value of a resistor. And when you are on the table had a "perfect" PI detector need you "know" that yoIt u adjust to terrain. In your case it takes "a lot" of knowledge. Good luck...

[Qiaozhi]

Dear friend. I made a new circuit board Gary pulse 1, with the new parts. Do very well.
But also that the original circuit board is the same problem. The total current 70 mA.
4-inch test 2.5CM coins, cans 8 inches.'s Largest iron 50CM. What is the reason for the request?
My coil is 0.51MM, 26 laps, 8 inches in diameter.

Your coil is probably about 400uH. This should be ok.
The problem seems to be the low average current taken by the circuit. The Gary1 detector has two selectable frequencies (100Hz and 1kHz) and a pulse width range of 165us to 275us. At f = 1kHz and t = 165us the average current should be above 200mA, probably more like 300mA. So either the frequency of your detector is too low or the pulse width is too short, or both. Please measure the frequency and pulse width and then tell us the answer.

[chemelec]

Average Current for the Pulse-1 on 100 Hz, is about 100 to 120 mA when the coil has a DC Resistance of around one Ohm.
His Coil is SMALLER Wire, Causing the Lower Current and Sensitivity.

If he increase the Freuqency to 1000hZ, it will help somewhat.

[yhl]

Today I tested a friend 1000HZ depth increased. Current is to 230MA
. Single coil circuit you do use the frequency 1000HZ

[yhl]

Today, when I tested the frequency 1000HZ. Current to the 230MA. Testing the depth increased. You do pulse 1 circuit is 1000HZ frequency?

[yhl]

Circuit ,when the detection of low because of 100HZ NE555 problem? The circuit must be a CMOS.ICM7555 it?

[Qiaozhi]

Circuit ,when the detection of low because of 100HZ NE555 problem? The circuit must be a CMOS.ICM7555 it?

What is your question?
Are you saying that you cannot switch the detector to output 1000Hz?
In other words, is your detector only working at 100Hz?

[chemelec]

Circuit ,when the detection of low because of 100HZ NE555 problem? The circuit must be a CMOS.ICM7555 it?

I Don't understand What your asking.

However, The Kits I sell ALL have the NE555's in them.
NEVER the 7555, C-Mos Version.

And Current draw is Partly a Function of Frequency, But it is Also changed by changing the Pulse Width. 230mA is getting a Bit too High.

[yhl]

Hello my friend

I mean, I had the circuit to 1000HZ. Current 230MA. Depth increased.
Perhaps the problem is the coil. I have done two circuit boards are the same. I use the NE555. You are also right?
Hope is caused by detection of small low coil current.

[chemelec]

I mean, I had the circuit to 1000HZ. Current 230MA. Depth increased.
Perhaps the problem is the coil. I have done two circuit boards are the same. I use the NE555. You are also right?
Hope is caused by detection of small low coil current.

Actually it Sounds like you have other Problems.