HI Peter,
JVC is commonly known as the Japanese Victor Company and they were in a joint venture with the Lowry Organ people in the 70,s and were building the amplifiers for the Lowrey Organs and KEYBOARDS. I don't know of any association with Technics but could have been. I still have a Lowrey Keyboard and a pair of JVC amps that came with it for an extra five hundred dollars. The keyboard alone was 2600.00 USD. The amps are 35 watt each and have 5 channel EQ's with 12 inch speakers. Good stuff for their time. I use them for small venues and to pack around in the Motorhome at 25 pounds each.
The Keyboard that you hung around your neck was a Roland Remote Midi controller that controlled your organ or keyboard thru midi. I see lots of them now in used music stores and consignment centers.
That is about all I know about it.
Bebop