Help please,no tone

Posted: 3/25/2006 3:49:15 AM
cgiannouli

Joined: 3/25/2006

i just finished building a Silicon Chip Theremin Synthesiser and i'm trying to set up pitch and volume.I applied power and got, on pin 8 of IC2 and pin 6 of IC3,the right voltage +5.6V.I adjusted VR2 so as to have + 4.3V on pin 1 of IC2 and winded just a bit clockwise VR1 fron its fully anticlockwise position.I rotated slowly the slug of T2 and waited to hear a tone in the loudspeaker...Nothing at all.I continued rotating the slug of T2 ,i went from its start to its end position but no result.I moved the telescopic antenna to different lenghts,still nothing.My circuit is allright,no bad solderings or "open" lines.I moved just a little T1 and retried to adjust T2 still i get no tone in the loudspeaker.As fas as the volume plate,i have adjusted T4 in a good position and i get +1.7V at the cathode of diode D1.But without the pitch i have nothing.Help!Help!I have to make it work.And please,all hints and tips for adjustemnts are most welcomed.

You must be logged in to post a reply. Please log in or register for a new account.