Field Change Notices
CBS/Fender released eight of these technical notes to service centres in 1982 and 1983.
FCN2-001 - To prevent Dual Channel Boards from drifting beyond tuning range after warm up. Applies to model 2103, Serial Numbers 0011 through 0060.
FCN2-002 - To reduce noise on the 2MHz clock line thereby improving cassette load operations. Model 2103, Serial Numbers 0011 through 0106, 0108 through 0113, 0116, 0121, 0125, 0132, 0138, 0139, 0141, 0149, 0150, 0151.
FCN2-003 - To adjust balance in +5V digital current limit circuit, preventing power supply from blowing fuse. Model 2103, Serial Numbers 0011 through 0060.
FCN2-004 - To provide computer access to end of conversion from A/D converter. This prevents the Chroma from mysteriously changing its own parameter, modifying programs, switching selections, tapping the tapper, etc. Model 2103, Serial Numbers 0011 through 0106, 0108 through 0113, 0116, 0121, 0125, 0132, 0138, 0139, 0141, 0149 through 0151.
FCN2-005 - To insure the Dual Channel Boards tune properly during auto tune, and to prevent Dual Channel Boards from drifting beyond normal tuning range. Model 2103, Serial Numbers 0011 through 0106, 0108 through 0113, 0116, 0121, 0125, 0132, 0138, 0139, 0141, 0149 through 0151.
FCN3-006 - Power Supply update modifications. Model 2103, Serial Numbers 0011 through 0354.
FCN3-007 - To eliminate intermittent operationn of the XOFULL Flop, possibly causing external interface communications problems. Large capacitance keeps Z48A from pullling XOFULL line completely low preventing the Flop from reliably latching through Z48B. Smaller capacitance corrects this. Model 2103, Serial Numbers 0011 through 0439.
FCN3-008 - To delay the write Synthesizer Address Latch Strobe (WRSYNA), thereby preventing the previously latched address from falsely strobing the channels. This eliminates possible intermittent conditions when using the two output selects with linked and main programs. Model 2101 through 2104, and Expander, Model 1633, all Serial Numbers through 0800.