Hammond T200 page
modifications
In December 2005 I modified my T200 to give it more of a B3 sound. Here are the details, and links to the information sites.
POWER SUPPLY
Replaced C615, C616 and C618 with 4700µF / 50V
Replaced C617 with 2200µF / 63V
GENERAL
Replaced all electrolytic capacitors – this fixed hum and gave more reverb.
Adjusted reiterate balance preset (horizontal pot on RH end of organ)
Carsten Meyer mods:
Removed Miller capacitors from a 16’ to 1’ on upper manual
Removed Miller caps from 8’ and 4’ on lower manual
Changed R806 on recovery board from 47KΩ to 33KΩ
Adjusted R821 (vibrato board) to bring vibrato volume up to non-vibrato.
Changed filter resistors and caps on recovery board. Note: put a trimpot in series with C860 for tone control.
Mod to C853 and C856 not done.
1n5 capacitor added in parallel with R821 on vibrato board.
Removed 0.82µF cap. on percussion board.
Added 0.022µF cap on percussion board.
Added 330KΩ in parallel with 1MΩ behind Reiteration Tab.
Replaced 3M3Ω with 820KΩ behind Reiteration Tab.
Changed percussion presets to:
Chimes -> 4’ slow
Celesta -> 4’ fast
Guitar -> 2 2/3’ slow
Marimba -> 2 2/3’ fast
(3 x 33K resistors). Note R263 was already 33KΩ
Added 15KΩ resistor in parallel with on chorus Tab.
Bernhard Schmidt mods:
22nF capacitor added in parallel with 100KΩ on percussion board.
Frederick Somerville's page:
http://www1.tripnet.se/~flm/hammond/diff.htm
POWER SUPPLY
Replaced C615, C616 and C618 with 4700µF / 50V
Replaced C617 with 2200µF / 63V
GENERAL
Replaced all electrolytic capacitors – this fixed hum and gave more reverb.
Adjusted reiterate balance preset (horizontal pot on RH end of organ)
Carsten Meyer mods:
Removed Miller capacitors from a 16’ to 1’ on upper manual
Removed Miller caps from 8’ and 4’ on lower manual
Changed R806 on recovery board from 47KΩ to 33KΩ
Adjusted R821 (vibrato board) to bring vibrato volume up to non-vibrato.
Changed filter resistors and caps on recovery board. Note: put a trimpot in series with C860 for tone control.
Mod to C853 and C856 not done.
1n5 capacitor added in parallel with R821 on vibrato board.
Removed 0.82µF cap. on percussion board.
Added 0.022µF cap on percussion board.
Added 330KΩ in parallel with 1MΩ behind Reiteration Tab.
Replaced 3M3Ω with 820KΩ behind Reiteration Tab.
Changed percussion presets to:
Chimes -> 4’ slow
Celesta -> 4’ fast
Guitar -> 2 2/3’ slow
Marimba -> 2 2/3’ fast
(3 x 33K resistors). Note R263 was already 33KΩ
Added 15KΩ resistor in parallel with on chorus Tab.
Bernhard Schmidt mods:
22nF capacitor added in parallel with 100KΩ on percussion board.
Frederick Somerville's page:
http://www1.tripnet.se/~flm/hammond/diff.htm
