TGSL mode CMS

[zoomix]

Hi all,

The smd TGSL is ok for me, I just solder the track that connects pin 2 and 7 of 4024.

Discrimination works flawlessly

I 14.4khz and I tested different capacitor value to check if there was not a more powerful alternative frequency as I reach for the moment +-25cm with a piece of 2 euro.

The coils are set at 20 ° with a phase meter.
My coils are a precise 6mh for Tx and RX for 6.5mh

In this regard, I post the RAR file in the phasemeter DVM rubique "IGSL TGSL" on page 67

Very practical, it's my new year gift for geotech

If someone can give me some advice to improve the power of detection ca me interested.

thank you

[hugo]

Hi all,
The smd TGSL is ok for me, I just solder the track that connects pin 2 and 7 of 4024.
Discrimination works flawlessly
I 14.4khz and I tested different capacitor value to check if there was not a more powerful alternative frequency as I reach for the moment +-25cm with a piece of 2 euro.
The coils are set at 20 ° with a phase meter.
My coils are a precise 6mh for Tx and RX for 6.5mh
In this regard, I post the RAR file in the phasemeter DVM rubique "IGSL TGSL" on page 67
Very practical, it's my new year gift for geotech
If someone can give me some advice to improve the power of detection ca me interested.
thank you

Congratulations Zoomix !
What kind of coil do you have ? I think you can virtually reach 28-30cm with a 20cm coil.
My first tests gave about 35cm with a Minelab TS1000 coil in the air for a 2 euros coin.
And thank you for the phasemeter.
Regards,
Hugo

[zoomix]

Hello Hugo

This is the coil TGSL that I made based on the tutorial Dfbowers.
this is the second that I make and I have not yet filled epoxy. The inductance values are correct. I think I can improve in electronics, the frequency.

[hugo]

Hello Hugo
This is the coil TGSL that I made based on the tutorial Dfbowers.
this is the second that I make and I have not yet filled epoxy. The inductance values are correct. I think I can improve in electronics, the frequency.

Hello Zoomix,
Not sure you can play easily with the frequency.
The OPAMP filters will be out of range.
You better try to check points like :
1 - coil balance
2 - shielding (cable and enclosure)
3 - TX oscillator ? (see below)
4 - OPAMP (output offset, noise, etc)
Regards,
Hugo
Note : Can you post some pictures of your MD ?

[zoomix]

TGSL SMD

Hello Zoomix,
Not sure you can play easily with the frequency.
The OPAMP filters will be out of range.
You better try to check points like
1 - coil balance
2 - shielding (cable and enclosure)
3 - TX oscillator ? (see below)
4 - OPAMP (output offset, noise, etc)
Regards,
Hugo
Note : Can you post some pictures of your MD ?

Hi Hugo,

For oscillator this is same of diagram of TGSL EDU ...i think it's good.

I made a IGSL and the oscillator is same. IIf the oscillator coil TGSL must be like on your image, I do not understand anything. can you confirm?

THanks

[hugo]

Hi Hugo,
For oscillator this is same of diagram of TGSL EDU ...i think it's good.
I made a IGSL and the oscillator is same. IIf the oscillator coil TGSL must be like on your image, I do not understand anything. can you confirm?
THanks

Hello Zoomix,
Your oscillator is correct.
I've just sent you another schematic you can try (if you want !).
Bonne soirée,
Hugo

[zoomix]

Hello Zoomix,
Your oscillator is correct.
I've just sent you another schematic you can try (if you want !).
Bonne soirée,
Hugo

Hi hugo,

Ok thank you for the diagram. I think I réusssi improve detection power oscillator (original). I will post a link youtube video.

To test the capacitor RX and TX quickly, I put the cables on a test plate.

I have a very good result with 20nF on TX and RX on 15NF. I sound 50cent euro 30cm!

It is said that the detector will lose 25% of the land where the interest to get the power and the best settings before.

[hugo]

Hi hugo,
Ok thank you for the diagram. I think I réusssi improve detection power oscillator (original). I will post a link youtube video.
To test the capacitor RX and TX quickly, I put the cables on a test plate.
I have a very good result with 20nF on TX and RX on 15NF. I sound 50cent euro 30cm!
It is said that the detector will lose 25% of the land where the interest to get the power and the best settings before.

Very good news !
Keep going.

[zoomix]

I have a limit to 30cm with 50cent euro. I would like to improve the depth if possible before casting epoxy.

The discimination is very good and eliminates the GB ferrite. Sensitivity is less pronounced, there is little change to the change potentiometer.

As I did not crackle at full sensitivity, I could increase the gain. Can you see what I just change?

There is a resistance of 470k instead of 1M on some of the opamp ....

There are many discuss about improvement and I do not know where to look .....

Thank you for your advice

[Firebox]

Hi all,

today i have finished my TGSL SMD. When i turn it on, there is nothing! when I turned on the Coil Poti (needed for my IGSL Musketeer Coil on TGSL) a permanent "beep" comes. When i diconnect the TX the beep is off. Whats my problem???

[hugo]

Hi all,
today i have finished my TGSL SMD. When i turn it on, there is nothing! when I turned on the Coil Poti (needed for my IGSL Musketeer Coil on TGSL) a permanent "beep" comes. When i diconnect the TX the beep is off. Whats my problem???

Hi Firebox,
Please check the following points.
1 - Does this capacitor match with your coil ?
2 - What kind of capacitor it is ? bipolar or polarized ?
3 - Have you seen that the common connection is not in the middle ? It's the left one (2).
4 - You need an oscilloscope to adjust the pot located on the addon card for the Minalab coil. Set it to get a nice sine signal.
5 - Your MD can't oscillate (then can't generate -6.2V) without coil.

Good luck,
Hugo

[Firebox]

Hi Firebox,
Please check the following points.
1 - Does this capacitor match with your coil ?
2 - What kind of capacitor it is ? bipolar or polarized ?
3 - Have you seen that the common connection is not in the middle ? It's the left one (2).
4 - You need an oscilloscope to adjust the pot located on the addon card for the Minalab coil. Set it to get a nice sine signal.
5 - Your MD can't oscillate (then can't generate -6.2V) without coil.

Good luck,
Hugo

Hi Hugo!

Point 1 Yes, i use a 330nF on the addon Card for TX and a 19 nf on PCB for RX these are the same values like on my igsl Musketeer
Point 2 I use 10 uF bipolar capacitor
Point 3 I have made a picture from the switch connetion. Please check it, if its right
Point 5 Yes, i know that

Regards

Gerd

[hugo]

Hi Hugo!
Point 1 Yes, i use a 330nF on the addon Card for TX and a 19 nf on PCB for RX these are the same values like on my igsl Musketeer
Point 2 I use 10 uF bipolar capacitor
Point 3 I have made a picture from the switch connetion. Please check it, if its right
Point 5 Yes, i know that
Regards
Gerd

Hi Firebox,
1- Ok
2- The capacitor value is 4.7µF not 10µF. But this is not the problem you're talking about.
3- Reverse this two wires. The pad labeled 2 shoud be in the central pin of the switch.
Best regards,
Hugo

[Firebox]

Hi Firebox,
1- Ok
2- The capacitor value is 4.7µF not 10µF. But this is not the problem you're talking about.
3- Reverse this two wires. The pad labeled 2 shoud be in the central pin of the switch.
Best regards,
Hugo

Hi Hugo,

i have reversed the wires on the switch. When I turn the potentiometer on addon Board there are 3 states.
- no sound
- oscillating sound
- continuous tone

It is a small way between no sound, oscillating sound and continuous tone....

The RX Capacitors are the same like on my IGSL Musketeer. The Value of my selfmade coil are 1,04mH for TX and 14,24 mH for RX. On TX I use a 330nF and on RX i use a 19nF capacitor.

When I measure the negative voltage, it fluctuates from -2,3 to 4,9 Volt. It is a oscillating voltage, but it must be a permanent voltage!
So what´s the problem ??

Regards

Firebox

[hugo]

IMHO, the three states mean :
1- No oscillation at all
2- You just reach the level to make the 4024 works
3- The level is high enough and your negative voltage should be correct.
You better check the zener diode between the LM393 and the LM358 (audio).
I've got the same problem with a single 4148 diode. I've to put 2 diodes in serie.

If it doen't work, remove all IC from the sockets and go step by step. From RX to audio.
Start with supply, then RX, AM and DISC stages (all parts before the BC245) and then filters, comparators. Audio stage at the very last.

Regards,
Hugo