TESORO GOLDEN SABRE

[simonbaker]

hi to all
i would like to confirm some mesurements that i made..
i've got:
current to pcb= 26.7-27mA
from 7808=>7.98V
tx=7.29V DC(got no scope)
tx freaq:
-for 9.36mH-9.4mH,25.6ohm==>14.6kHz
-for 9.41-9.55mH,27.2ohm===>13.7kHz
(both coils just for mesurement..i know that they should be 6.5 and 6mH)

do You know how to mesure coil in and nuil it in the same time?..i mean i get 10 windings and mesure..another 10 and mesure again..??
thx
best regards to all
lunamay

Your measurements look very good and normal, although I wonder if your inductance measurements are correct? The frequency is right, but inductance very high. Maybe your .022 capacitor C2 is actually lower than spec. What inductance is your Receive coil?

It's hard to make the correct inductance of coils, just experience mainly. Follow experience of others, then make small adjustments. Binding (tightly wrapping and compressing) the coil can raise the inductance by up to 1 or 2 mH, so it's tough. I usually scrape a small spot of insulation on the wire, measure, then tape or coat with some insulator and wind some more, and plan for about 1 mH increase of inductance when wrapping. Or you can wind a lot and then measure and unwind if too much inductance -- that's probably best but wastes wire. It's the darn wrapping that is hard to predict, you need to try a few and see how it goes.

Regards,

-SB

[simonbaker]

A few relics.. Camp Meade - 1898 .. Most found with Shadow X5, but a several dozen found with TGSL!

Looks like excellent hunting there! Hope you put a thread somewhere describing the items.

Regards,

-SB

[lunamay]

hi to all
i would like to confirm some mesurements that i made..
i've got:
current to pcb= 26.7-27mA
from 7808=>7.98V
tx=7.29V DC(got no scope)
tx freaq:
-for 9.36mH-9.4mH,25.6ohm==>14.6kHz
-for 9.41-9.55mH,27.2ohm===>13.7kHz
(both coils just for mesurement..i know that they should be 6.5 and 6mH)

do You know how to mesure coil in and nuil it in the same time?..i mean i get 10 windings and mesure..another 10 and mesure again..??
thx
best regards to all
lunamay

[simonbaker]

USB-2 seems suitable. 4 conductor + copper ground along with foil and braided wire mesh.

Thanks. I tried a cheap S-Video cable once -- decided to cut it open and look. The shield wire was just a bare wire running alongside the others, no shielding effect, just a ground connection. Cheap!

-SB

[dfbowers]

Thanks. Good luck hunting. I'll bet's it's nice there in PA. Be interested what TGSL finds.

lunamay would like to get a TGSL circuit diagram showing voltages at all points. Since you have a good one, maybe some time you can show us what you measure. Of course some points depend on pots, which makes more work; CCW, Middle, CW probably needed. I'll do it if ever get hot machine.

Regards,

-SB

A few relics.. Camp Meade - 1898 .. Most found with Shadow X5, but a several dozen found with TGSL!

[dfbowers]

Thanks. And what do you use for the cable in your picture?

Regards,

-SB

USB-2 seems suitable. 4 conductor + copper ground along with foil and braided wire mesh.

[dfbowers]

dfbowers, excuse my ignorance, this comment raises questions. If you will kindly confirm if you need to connect eventually land in the places indicated in the photo would be very grateful.

I just have this and once I finish the circuit. Thank you

Rx "land" (Ground) is correct
Tx "land" (Ground) is not

[Virdi_248]

Sorry.. I see now. All you guys are right! I switched black and red and rewired Rx start and Rx stop to keep the right phase. Ground shield should be tied to R13 that goes to pin 6 (inverting)of u101a . Still 29cm on 1e coin. Audio seems to be slightly improved and sensitivity control seems to have more effect. Does make a difference! I have heard some comment that it does not make a difference, but now I believe that it does.
This is my second TGSL. I have to go check my first one now to see if that one is wired wrong as well.

I have been relic hunting with TGSL#1 already and I have dung things deep enough that I am comfortable with it. Usually if I take a shovel full of dirt and I find something still in the hole I have good comfort level with the machine.

I have been working a large Spanish -American war camp here and Pennsylvania and the farmer just powed today. Time to hit the fields a little..

Simon, I bought my IC sockets from Digikey (see attached).

ED90048-ND 8 PIN SOCKET $0.92
ED90049-ND 14 PIN SOCKET $1.42

Don

dfbowers, excuse my ignorance, this comment raises questions. If you will kindly confirm if you need to connect eventually land in the places indicated in the photo would be very grateful.

I just have this and once I finish the circuit. Thank you

[simonbaker]

...and I have dung things deep enough that I am comfortable with it...

we get the picture...

[simonbaker]

Sorry.. I see now. All you guys are right! I switched black and red and rewired Rx start and Rx stop to keep the right phase. Ground shield should be tied to R13 that goes to pin 6 (inverting)of u101a . Still 29cm on 1e coin. Audio seems to be slightly improved and sensitivity control seems to have more effect. Does make a difference! I have heard some comment that it does not make a difference, but now I believe that it does.
This is my second TGSL. I have to go check my first one now to see if that one is wired wrong as well.

I have been relic hunting with TGSL#1 already and I have dung things deep enough that I am comfortable with it. Usually if I take a shovel full of dirt and I find something still in the hole I have good comfort level with the machine.

I have been working a large Spanish -American war camp here and Pennsylvania and the farmer just powed today. Time to hit the fields a little..

Simon, I bought my IC sockets from Digikey (see attached).

ED90048-ND 8 PIN SOCKET $0.92
ED90049-ND 14 PIN SOCKET $1.42

Don

Thanks. Good luck hunting. I'll bet's it's nice there in PA. Be interested what TGSL finds.

lunamay would like to get a TGSL circuit diagram showing voltages at all points. Since you have a good one, maybe some time you can show us what you measure. Of course some points depend on pots, which makes more work; CCW, Middle, CW probably needed. I'll do it if ever get hot machine.

Regards,

-SB

[dfbowers]

Hi Don:

It looks from your pictures that you ground the RX lead non-standardly at the shield. Other docs somewhere say to ground the lead that goes to the inverting input of the LF353. Am I correct that you ground the lead that goes to the non-inverting input?

Yet you seem to have excellent TGSL. So does it matter which RX lead is grounded at the shield? Can you try grounding the other RX lead at the shield and tell us what the difference is? Also, what happens if you don't ground the lead at all?

BTW: your IC sockets look very high quality. Where do you get them and how much do they cost?

Regards,

-SB

Sorry.. I see now. All you guys are right! I switched black and red and rewired Rx start and Rx stop to keep the right phase. Ground shield should be tied to R13 that goes to pin 6 (inverting)of u101a . Still 29cm on 1e coin. Audio seems to be slightly improved and sensitivity control seems to have more effect. Does make a difference! I have heard some comment that it does not make a difference, but now I believe that it does.
This is my second TGSL. I have to go check my first one now to see if that one is wired wrong as well.

I have been relic hunting with TGSL#1 already and I have dung things deep enough that I am comfortable with it. Usually if I take a shovel full of dirt and I find something still in the hole I have good comfort level with the machine.

I have been working a large Spanish -American war camp here and Pennsylvania and the farmer just powed today. Time to hit the fields a little..

Simon, I bought my IC sockets from Digikey (see attached).

ED90048-ND 8 PIN SOCKET $0.92
ED90049-ND 14 PIN SOCKET $1.42

Don

[simonbaker]

Look at colors.. does this help at all? Bare GROUND wire in cable goes to same connection as GREEN wire on PCB.

Does this help you at all?


Good luck!

Don

Hi Don:

It looks from your pictures that you ground the RX lead non-standardly at the shield. Other docs somewhere say to ground the lead that goes to the inverting input of the LF353. Am I correct that you ground the lead that goes to the non-inverting input?

Yet you seem to have excellent TGSL. So does it matter which RX lead is grounded at the shield? Can you try grounding the other RX lead at the shield and tell us what the difference is? Also, what happens if you don't ground the lead at all?

BTW: your IC sockets look very high quality. Where do you get them and how much do they cost?

Regards,

-SB

[simonbaker]

Simon,

I have been using 22 AWG (stranded) from Radio Shack. I think it comes in a few different colors.


Don

Thanks. And what do you use for the cable in your picture?

Regards,

-SB

[Virdi_248]

please read before asking
Look closely at the photos, is contrary

Sorry I have already set in the photo.

If I'm right. Faraday (tx) connected (end tx)
Faraday (rx) connected to (final rx)

Language is a big problem. Apologies.

[geminis74]

please read before asking
Look closely at the photos, is contrary