Regulation - Voicing - Tuning - Cleaning - Part Replacement
Suitcase: Mains Conversion 115V ->230V (and reverse)
Electronic Repair - Low Noise Mod
Low Hum Mod (Neutrik PowerCon, shielded power wiring, Cover shielding)
Ground loop eradication - Transformer balanced Line Out Phones / XLR.
For Feltwork and mechanical works I can recommend Christian Radtke of Rhodes Service
Berlin.