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Geddon

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About Geddon

  • Birthday 09/15/1981

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  1. Good suggestions, thanks. I have 3 c64 psus so i will give them all a try. I wont report back here until i have checked every possibility! I am still baffled but if i have to have a mono engine 1, well that will maybe have to do (for now!) :)
  2. OK so I double-checked the voltages again. It seems that sometimes when I power up the machine there is no power-up jingle, and all pin 28s of all sid (but sometimes just sid 1) read 3v. But then if I power-off and on again, the jingle plays and the voltage reads 11.9, even on sid 1. But in both cases, the audio of sid 1 still leaks across channels, and the osc 3 still glitches. Bah! sidsfront.bmpsidsback1.bmpsidsback2.bmpsidsback3.bmpboardback1.bmpboardfront1.bmp Edit- sometimes when modulation matrix, there are no leds lit in meter mode, when usually there would be for that patch. Reset power usually fixes this. I tried my spare c64 power brick, just in case it was that but the problems persist. Im wondering if i should just pull sid 2 and have mono engine 1? I dont want to hog all your time for my machine.
  3. Oops, yes i must have moved the jumper recently when i was checking stuff. The shame! Anyway, i put it back to 12v but now pin 28 only reads 3v. In addition, i removed sids one at a time and checked the audio outs. The sound only leaks to both channels when both sids are in. When either left or right sid is in, the audio comes from the correct channel. Only oscillator 3 of sid L is glitchy. With both sids in, if i play just osc 1,2 or 3 of left channel, the audio comes from the left and only osc 3 glitches. If i play just the right channel, sound comes from both channels but the glitches are heard only on the left. Im not able to upload any pictures til tomorrow, my new flat has no broadband yet so ive been using my phone. I will borrow a friends computer tomorrow afternoon. I took pics of the core section like you suggested. Is there something in paeticular to look for? Or just bad soldering/missing components? I will tell you that everything is there, but you cant trust anybody! Sorry for the long post but thanks again.
  4. Narrowing it down... Pin 28 of sid 1 reads 9v, as opposed to 11.9v of the other sids (all sids are 6581s). Pin 25 reads 5.1v on all sids so thats ok. When i first performed voltage checks during construction everything was a-ok, so does that mean that the problem lies within a component? Maybe within the pic? Sorry im not sure how to edit my posts. If i check for continuity between pin 14 and 28 of sid 1, my meter doesnt beep, but it does with other sids.
  5. I forgot to mention, i have been using the 6.3mm sid 1 output but the effect is the same from the 3.5mm. Another few things i have noticed when using engine 1- Using init. patch on left and right channels and all oscs set to pulse, when using the "detune" function the changes are not smooth like the other engines. It is like steps, where the pitch of osc 3 changes eratically. When i play a note and bend it with the wheel on my keyboard, osc 3 of both channels glitches and changes erratically. The fun continues...:)
  6. Thanks very much for the advice hawkeye. Your cs construction guide has been my trusty reading companion for quite a while! The machine is a beast, i shouldnt complain really because 3 of the four cores are spot-on and sound amazing. Ive been having a lot of fun creating sounds and learning the menus. But i just want it to be perfect! Well, maybe not perfect, i already had to desolder a bad encoder and a couple more are a bit funky but i can live with that for now. After more testing, the problem seems to have changed to something more simple. Sid 1 sounds on both left and right channels, and sid 2 sounds on both channels too. Ive swapped sids over, and also swapped pairs and the problem stays with audio output 1. And the ensemble is definitely not set to mono! Ive tested the pins of the audio out jacks with my multimeter for connectivity and all test consistently so i dont think the problem is there. I cant see any shorts, or bad solder points and i reflowed the solder on a few that looked 'dodgy'. I will keep looking and trying, those sids are worth it.
  7. Ok im really struggling with this. I assume it must be a simple problem to resolve, as no one has replied. But i just cant figure it out. Ive been studying the sid datasheet but to no avail. Ive spent almost a year collecting the parts, reading these forums, the construction guides etc. Ive been really careful, methodical, patient with every aspect of the build. There have been many times when i had questions but found it far more educational and fun to find the answers myself. But for this one im stumped. I dont expect to be handed the answer on a plate, but if someone could please just point me in the right direction i would be eternally grateful! Thanks again, Adam.
  8. Sorry, ignore that last question about sid numbers, i was having a 'special' moment :b
  9. I have noticed that sid engine 1, left sid does not produce any sound from oscs 2 and 3. Also, the right sid osc 1 outputs to both speakers, while oscs 2 and 3 only output to the right speaker. On all oscs which do not output a sound there is a small pop when a note is played. Dumb question, but maybe i have been swapping wrong sids. Which sid is number one on the board, the far left?
  10. On closer inspection, the audio from the right sid of engine 1 is coming from both speakers. But i dont see any short.
  11. Hi everyone, im almost finished with my mb6581 build but having a lil problem with sid engine 1. I followed the first steps of the midibox sid v2 manual and created a basic tone (fat pulse). It sounds great on engines 2,3 and 4, but on engine 1 the left channel sounds different. Its hard to explain, but its not as thick a sound. Like maybe an osc or two are missing. Ive swapped sids around and the problem persists so i know they're ok. Im sorry im not able to upload a sample at the moment but is there anything i can do to test the circuit? Do you think it may be a capacitor problem? Ive searched the forums but havent found anything similar. I hope i have given enough info for someone to please help! Thanks, Adam.
  12. Thanks for the quick reply Hawkeye. As far as I can tell, the best thing for me to do is just give it a try, right? Keep up the good work!
  13. Just wow! That is an amazing machine inside and out, a literal work of art, extremely well done and congratulations. The tutorial is really well written too, humorous but very informative! I'd love to build a machine like this but I am a complete beginner so I think its out of my league for now. I've been looking at the sammichSID and I reckon I could do that. Hopefully there are some kits left, but as I am impatient for that gritty SID sound I've decided to build a basic stereo midibox. Do you know if there are any walkthroughs as clear as this for a noob like me? I've looked at the walkthroughs on the site and I think eveything is there, but its a little scattered and I'm not sure if I've missed anything. Have you written any more of these? I think I could build anything if you were explaining it! Anyhow, thanks for an entertaining read, Adam.
  14. Hey guys, I'm looking for a sammichSID kit. Does anyone know if they're still available? I have 2 6581's but they need a home! Sorry if this question has been asked a million times already, if so, can someone point me in the right direction for an answer? Thanks, Adam.
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