This webpage can provide some user manuals and other documentaion pertaining to the specific Tektronix models, however a company called IML (Instrumentation and Metrology Labs) in Hampton New Hampshire, is now the authorized service center for repair and calibration for these units, including models beginning with: OTS..., CTS..., SJ..., GB..., PB..., ST..., CSA..., etc.

IML's contact information is: