Lexicon Model 200 Replacement Input/Output Filter PCB

Replacement Filter board for the Lexicon Model 200. If your M200 uses the canned Murata filters, Over time these overheat and leak a rubberized epoxy potting material all over the main board, requiring hours of repair time. They are also a likely culprit if you are hearing nasty high frequency digital trash in your reverb signal.At one point, instead of using these Murata filter units, Lexicon manufactured their own 9-pole 10.5kHz low pass filter modules in-house. Thankfully, the schematics and documentation for these boards are in the original service manual, and I was able to make a faithful copy and repair my M200 (others have since successfully fixed their units with these as well).

I had considered designing these for surface mount devices for ease of manufacturing. In the end, I decided to keep it through hole to allow the use of 2200pf 1% polystyrene capacitors as the original spec'd for precision filtering. It means you need to populate a pretty tight board by hand, though- we're talking intermediate soldering abilities here. You also need to desolder the original modules, an unused op amp, and some unpopulated pads filled from the original wave soldering process. Lexicon designed a single main board for both filter types, so these are drop-in after some desoldering.These are high quality gold-plated circuit boards and can be used for both input and output filters. Refer to the original manual page (3rd pic) to determine the resistor values you need as they differ between the two. The resistor designations (R1, R15, etc) on the PCB match that of the original schematic and components table shown.

Final pic is the board assembled with components for reference. To be clear- only the PCB is included in this listing.