Dr. Doug Millar EdD., K6JEY might be sending us a copy of this instruction manual for this waveguide. Waiting for his reply after he asked if we wanted it. --Jyohe (talk) 18:03, 31 July 2019 (PDT)
Update: Doug said he'd scan the manual and send it via email in "about" a week. Nice. --Jyohe (talk) 18:34, 31 July 2019 (PDT)
Update #2: Doug said he would, instead, mail the whole manual to me so I'll see about scanning it into a single PDF file. --Jyohe (talk) 17:59, 1 August 2019 (PDT)
Received the WM490 Instruction Manual from Doug and have scanned it, converted the PDF to be searchable with Abbyy OCR software and put it up on the page for users to download. Thanks for Doug Millar for his contribution. The actual paper copy of the manual is going to be donated to the VintageTek Museum on the Tektronix campus in Beaverton.