MATRIXSYNTH: Oberheim OB-XA SN 824319


Saturday, February 25, 2023

Oberheim OB-XA SN 824319

Note: Auction links are affiliate links for which the site may be compensated.



via this auction

"This particular one spent some time on the road in the early/mid 80s and has lived in a studio ever since. Collecting dust for 15 or so years, it got a little old and finicky - so I took it to Main Drag Music in Brooklyn NY and had it overhauled. (specific work done listed below)

Repair Parts-TKKeyboard Bushing X61, Capacitors, IC Sokcet 14p X2, 6800uF 25V Axial X1m 3300uF 50V Axial x1, 3300uF 35V Axial X1, 2200uF 50V Axial X1, 470uF 35VAxial X1, D Capacitors 15uf 50V x15, 47uF 50V x32, Battery 2/3A with Solder TAB x1, Bender Pot 10K Long Shaft 1/4. X1, Cmos IC 4051 X9, OP AMP IC TL084 X1, CA3086 X1, LM741 X1, DIP Switch 8P X1, Oval #8-32 Screw and Cup washer set X12, Trim 3296W Multi Turn Trim 10K x16, 100K x16 for VCO. Trims for Bender Unit X8, Trims 5K x1, 100k x1 for DA converter section. Hi pricision Resistor 100K 0.1% X32, 750K 0.1% X16, 1M 0.1% x16, Terminals for MOLEX Connector X178, Screws x10, Wires,

Old Keyboard bushing for Kyboard, Replaced All Bushing and Adjusted Space and Height for Keys. Cleaned up and Lubed Bus Bars and All J-Wire Contact. Bad Connection VOice Selct DIP Switch, Replaced. Cleaned up And Lubed all Switches and Pots. Replaced Electrolytic Capacitors for Power Supply and Power Lines. checked and Adjusted Voltages. Bad Connection on Molex connectors, Replaced all Terminal for Molex Conextors ( x178), old Pricision Resistors are out of spec. Replaced Resistors for VCO ( for Auto Tune. ) Voice #8, Out of tune, Replaced CA3086 VCO IC. Old Trimmers are no good. Replaced Almost Trimmers. Old 4051 CMos ics are no good. Replaced all 4051. Replaced all Trims. pitch bender is not good, Cneter is not stay, Replaced Pitch bend Pot 10K Long Shaft. Old Cmos Ics on Main CPU board section. Replaced 4051 x9. checked and Adjusted Voltages. Re-caliberated D/A. All Voices. Voice #4, Filter is open, IC is broken, Replaced 741. Upper filter is open, Bad connection, TRACK line, Cleaned up ribbon cable.

Re-calibrated Couple of Times Checked and burn in test."

No comments:

Post a Comment

To reduce spam, comments for posts older than one week are not displayed until approved, usually same day. Do not insult people. For items for sale, do not ask if it is still available. Check the auction link and search for the item. Auctions are from various sellers and expire over time. Posts remain for the pics and historical purposes. This site is meant to be a daily snapshot of some of what was out there in the world of synths.

PREVIOUS PAGE NEXT PAGE HOME


Patch n Tweak
Switched On Make Synthesizer Evolution Vintage Synthesizers Creating Sound Fundlementals of Synthesizer Programming Kraftwerk

© Matrixsynth - All posts are presented here for informative, historical and educative purposes as applicable within fair use.
MATRIXSYNTH is supported by affiliate links that use cookies to track clickthroughs and sales. See the privacy policy for details.
MATRIXSYNTH - EVERYTHING SYNTH