I can remember taking apart a phillips TV turret tuner dating from the 60's. The higher frequency "biscuits" (pcbs which set the frequency and rotated with switch position) used printed pcb inductors. Richard P Nigel Goodwin cc: Sent by: pic Subject: Re: [EE]: Coil Imprinted on PCB. Patented microcontrolle r discussion list 01/12/00 09:17 Please respond to pic microcontrolle r discussion list In message <3A26A356.393CBB40@UAlberta.ca>, Robert Rolf writes >Yes, that form would appear not be covered by THIS patent. The claims >make no mention of a single sided version, and I think that's how the >test gear was done. Grundig TV's from the late 1970's used a single sided PCB coil for the sound demodulator - the coil was tuned to either 6MHz (UK) or 5.5MHz (rest of Europe). The coil incorporated a number of small shorting paths at one end, these were cut by a machine during manufacture to adjust the resonant frequency, it was really neat - a circular cut was made on the PCB tracks to tune the circuit :-). Made it a real pain to try and change for sets bought over from Europe though!. -- Nigel. /--------------------------------------------------------------\ | Nigel Goodwin | Internet : nigelg@lpilsley.co.uk | | Lower Pilsley | Web Page : http://www.lpilsley.co.uk | | Chesterfield | Official site for Shin Ki and New Spirit | | England | Ju Jitsu | \--------------------------------------------------------------/ -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body