FTS 6102 Frequency Comparator -info needed Does anyone have any info on this Frequency & Time Systems unit? I have 3 and each is slightly different externally but the innards seem to be the same. Each unit has a low 2-digit S/N so I’m not sure how many were actually made or if any of them were production units. I.C. date codes indicate a 1987 date. I have quickly checked the circuit board to see if I could figure out what goes on and have included a link to a photo of the input section of the circuit board. There are 2 floating BNC inputs (A & B) that go through isolation transformers to buffers then to a phase detector. From the parts used it appears the circuit might be usable from near d.c. to about 100Mhz. The phase detector gives a d.c. voltage proportional to the phase difference and seems to be followed by RC low-pass filtering feeding the op-amp, which seems to make sense. There are 2 output BNC connectors marked ‘A-B’ and ‘analog’ There are also two LM211 voltage comparators that may be used to trigger the 8-digit counter chip that drives the front panel display. You can select 3 of the 8 digits with a switch and apparently the numeric value of that 3-digit number is converted with a 12-bit D-A converter to drive a recorder or whatever. Four decade averaging periods are also selectable. There is also a 25 pin ‘D’ connector on the rear marked ‘controller’ but I’m not sure what that does as if it doesn't seem necessary to use the unit as a comparator. A quick test indicates the units at least work. More testing is needed to see how useful they might be. Any information would be appreciated. -Richard Front Panel photo link _http://farm3.static.flickr.com/2665/4203550480_70f27cb15e.jpg_ (http://farm3.static.flickr.com/2665/4203550480_70f27cb15e.jpg) Circuit Board photo link _ http://farm3.static.flickr.com/2785/4203550698_cb648b4e35.jpg_ (http://farm3.static.flickr.com/2785/4203550698_cb648b4e35.jpg) _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
