TESORO GOLDEN SABRE

[Hyena]

In my excperience, null (voltage nor phase) does not affect GB nor Disc range.
Its Rx resonant frequency, which affect this.


Regardless on coils and oscilator you use: Measure precisely Tx frequency.


Now you have 2 options:


1) Coil tester: Use coil tester with your Rx and Rx cap. Hit Rx frequency to be 1,11 * Tx frequency.
2) Inductance measurement: precisely measure Rx inductance - calculate Rx capacitor value to Rx reach 1,11* Tx frequency.


Does not matter what way you choose. Does not matter on null. Only resonant frequency ratio matter.

Play with it a little and you will see...

It is not simply the RX Null Voltage --- it is the PHASE difference between the TX and RX that determines the discrimination.

It is much better to use a two channel O'scope when adjusting the coil NULL.
Set the Null so that the RX wave lags the TX by about 20 degrees.

Second, I assume you wound the TX and RX coils with about 0.5mH difference in inductance. This is also critical to obtin the correct phase shift and have discrimination work.

Last is to have the polarity of the coils connected to the TGS correct.
Possible you simply have the RX coil connected backwards. Try swapping the only the RX coil leads.

[waltr]

Something strange here .i make an 27dd new coil.nulled at 2.2mv ,in all mode .when tested in all mode it works good but disc mode doest work.it rejects all the coins and only the ferroes beep,it should rejects them but it beeps.on the concentric coil the circut worked good at disc mode.now in dd coil the frequency is 15.5khz��

It is not simply the RX Null Voltage --- it is the PHASE difference between the TX and RX that determines the discrimination.

It is much better to use a two channel O'scope when adjusting the coil NULL.
Set the Null so that the RX wave lags the TX by about 20 degrees.

Second, I assume you wound the TX and RX coils with about 0.5mH difference in inductance. This is also critical to obtin the correct phase shift and have discrimination work.

Last is to have the polarity of the coils connected to the TGS correct.
Possible you simply have the RX coil connected backwards. Try swapping the only the RX coil leads.

[Ozoz_xba]

I should get 4mv on rx and try it again if disc is working.
By the way my tx and rx is made by 0.45 wire...

[Ozoz_xba]

Something strange here .i make an 27dd new coil.nulled at 2.2mv ,in all mode .when tested in all mode it works good but disc mode doest work.it rejects all the coins and only the ferroes beep,it should rejects them but it beeps.on the concentric coil the circut worked good at disc mode.now in dd coil the frequency is 15.5khz��

[ricalbertvig]

I was able to solve the problem ... it was the 8v regulator .. I was giving a 3v output .. it restores everything right now

[ricalbertvig]

the problem is when putting the coil, permanent noise without being able to control the audio .. without coil there is no audio

[kt315]

this schematic is not working right without coil - no second/negative rail voltage. do a dummy temporary coil with 6mH (milli-) and connect
it to TX.

[ricalbertvig]

hello .. I finished mounting the pcb .. I have a problem ... to put tx generates a permanent noise audo .. what can be the cause?

[kt315]

Merry Christmas amigo

[Chiringo]

HI
thanks for your help!!
Merry Christmas

[kt315]

can. pot 100k.

[Chiringo]

Hello everyone and Merry Christmas
can some companion put some small scheme or drawing of com adding a potentiometer for volume control to TGSL EDU?
Thanks in advance

[pustareka]

Tesoro Eldorado

https://vk.com/topic-33752123_28990794?offset=0

[liekwang]

thanks, kt315 for this help, my beautiful pcb, I will try to study every component list, is it in my country, again thanks kt315

[kt315]

GMT gerber files