tgsl -5v problem

[nick holas]

hi all
i finished my tgsl ,switch on and ........ nothing sound.

i can found 8v,12v but can't find -5v , i 've read -5v is obtained by tx oscilator but can't have it ;i only have 0.69v on gnd pin of IC's

got an idea ????thanks

[mschmahl]

Have you connect your coil?

[nick holas]

thanks for your reply
i've connected my coil,i've changed the TX and RX coil, i've changed the begin between the finish of twice coil and ........nothing!!! no sound i think the oscillator don't work.
another idea ??

[nick holas]

hi
Where come the -5v on the scheme ,can i change it by a 7905? and where can i connect it

[mschmahl]

Your oscillator must work. You can check it on Pin 1 of cd4024. There must be a frequenz. How much is it? How many nF are on C1 and C2? How many uH has your TX-Coil?

[nick holas]

hi
in pin 1 of cd4024 have got 10,68khz and 5.06v ,on pin 4 of LF353 i have 0.6v.C1 C2 are like in scheme 0.22 and 0.022.
thanks

[mschmahl]

Than your oscillator work´s right. You must get -6 V on the negativ pole of C11. Is Q3 or Q4 wrong?

[nick holas]

thanks
C11 is ceramic so non polarized condo (near U102b pin 7 )can you tell me what c11 is on my scheme ??
Q3 or Q4 ??? i only have TR.. might it be TR7 and TR8 on my scheme
Thanks for your patience.

[nick holas]

ive 5.29v on pin 1 cd4024
7.90v on pin 14 cd4024
0.69v on pin 4 LF353
7089v on pin 8 LF353
always no sound and no -5v discouraged!!!!!

[mschmahl]

can you post your schematic?

[nick holas]

or in the forum in 'tgsl complete detail' trhead if it d'ont work

[nick holas]

i solve the problem.
bd140 was dead i change it and it works thanks all
happy new year