new members = old questions (+ proposal for the future this site)
2005-03-31 by koookaburra
**** A great hail! to the community from South of France :-) I've been gathering tons of useful tips about the polysix on the web and I've decided to purchase one which needs a fix (battery leakage). [ BTW I can provide you a personal webstorage to host a site and a forum (mysql) for free and without advertisement. The Polysix deserves it and you guys deserve it too ! So if the moderator of this mailing-list is interested he can contact me anytime ]**** * Things that I've already done : - Replacement of 4011 (x2) 4048 (x2) 74LS08 (x2), 4051 (x1), TL072 (x1) chips : I'm lucky for they were socket'ed and not soldered. - Continuity test of the whole board (I think I should maybe double-check but I've no schematics of the whole board, only the battery area) - Resoldering few tracks * Things I've noticed : - Non-working functions : VCF : Cutoff EG Intensity KBD Track MG : Frequency Delay Level MOD switch (VCO, VCA, VCF) MG led doesn't light up (As I've no experience of the P6 I can't tell if the Resonnance is ok : it sounds a bit harsh to me) - It requires a warm-up usually 10 seconds (and sometimes 5 minutes) before the whole lights turns back to normal (during the warm-up they are all lighted-up) - Sometimes the sound gets distorted while I'm playing, or the volume decreases suddenly and then turns back to normal. Usually after a 15-30 minutes test the synth does not want to play anymore or acts too weird to continue the test. * Questions I'm asking : - Does the continuity test (with a multimeter) is an accurate way to check if the circuits are ok ? `Cause I've noticed several soldering holes which look strange and I'm suspicious about them (see picture here : http://16days.free.fr/Polysix/P6-1.jpg ). On the other hand when I test the tracks between two of these holes the multimeter buzzes normaly - Anyway is it possible to get an accurate diagnostic as long as I've not resoldered a new battery ? - I was wondering about the capacitors : do you think I could be a cause of the malfunctions ? - Is there a specific area on the board involved in the Cutoff and MG functions ? - I've several NEC 8084C chips and I wonder if I can replace the original one by one of those. Or does it require reprograming prior to the replacement ? **** Thank you for your valuable help, especially OldCrow and his precious website.****