Kike Posted March 1, 2016 Report Share Posted March 1, 2016 Hi I am trying to build a SIDv2, actually a TWINSID from yodabe. I have build only a main board for now, and the sid worked, when I tried the sid tomorrow there was no sound. So I have tried the testtone app to find out Is there a problem with the output amp. I have connected the 8 pin and the 27 pin and there is no sound but when i touch the wire with my hand there is a sound, What? Strange. Can someone give me an advice what to do, what to replace, what to check? I have put the sid to other socket on the board and it works like a charm. this is the link of the project: http://www.midibox.org/dokuwiki/doku.php?id=mb-twinsid By the way, the left sid on the main board is not working Thanks, Kike Quote Link to comment Share on other sites More sharing options...
Janis1279 Posted March 2, 2016 Report Share Posted March 2, 2016 Hi Kike, For the basic Sid part schematic understanding it's a good habit to use a MBHP_SID_V3 schematic from the Sid Module section. It can help to understand the audio path part and the control pin part of the Sid chip. The schematic is the same, I think. There are a lot of soldered wires - jumpers on the Twinsid main board. If you are used the same layout board you need to check a presence of every jumper - wire , under the ic's, too. Visually check all solder places on the pcb, not the shorts between the traces,too. To check a non solderable jumpers too. Supply voltages tests idea are similar to the sammichSID_build_guide_v1_0.zip from page 18, but there are another components layout of course. To check: right supply voltages for your sids , the right nominal similar capacitors for the sids oscillators on the sid pins1/2 and 3/4. Regards, Janis Quote Link to comment Share on other sites More sharing options...
Kike Posted March 3, 2016 Author Report Share Posted March 3, 2016 Hi Janis Thanks for the help. I have checked everything. I am using 8580 chips, put a 22nf caps on the pins1/2 and 3/4. Put a pullup resistor on the lcd Voltages are fine, 9V and 5V. I bypassed power from the TWINSID board and build power supply that was suggested by Thorsten. I have tried yesterday the socket that worked the first time and now I hear very high noise on the output, SID works Noise changes when using midi keyboard in mios studio. It is some kind of flickering noise. I am going to etch another board, going mad with this one. Regards Kike Quote Link to comment Share on other sites More sharing options...
Janis1279 Posted March 3, 2016 Report Share Posted March 3, 2016 Hi Kike, Are the Sid chips audio input pins 26 tied to ground (with the small jumpers)? Regards, Janis Quote Link to comment Share on other sites More sharing options...
Kike Posted March 4, 2016 Author Report Share Posted March 4, 2016 No, i didn't tied them to the ground. How did I forget that. I will try tonight and see what is going to happen Quote Link to comment Share on other sites More sharing options...
Kike Posted March 4, 2016 Author Report Share Posted March 4, 2016 I have grounded the input pins and still nothing. Going to etch another board, this is not working. But this time I will not go with twinsid. Quote Link to comment Share on other sites More sharing options...
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