Electricity: measuring and testing – Measuring – testing – or sensing electricity – per se – Frequency of cyclic current or voltage
Patent
1983-09-26
1986-05-06
Tokar, Michael J.
Electricity: measuring and testing
Measuring, testing, or sensing electricity, per se
Frequency of cyclic current or voltage
331 38, G01R 2314
Patent
active
045874832
ABSTRACT:
The circuit arrangement described measures the time when a frequency F.sub.o, changing towards a desired frequency value, differs by not more than a predetermined amount (e.g. 100 Hz) from the desired value. Initially F.sub.o is mixed with the sum of 10 MHz and the new desired value for F.sub.o. The lower sideband is selected and thus produces a frequency F.sub.1 which is thus always 10 MHz when F.sub.o reaches its desired value (which may be variable). The circuit therefore has to measure when F.sub.1 comes within 100 Hz of 10 MHz. Initially F.sub.1 is multiplied by a predetermined multiplication factor (.times.100) and the product subtracted from a reference frequency. The latter is the sum of a fixed frequency of 300 KHz and of 10 GHz (i.e. 10 MHz multiplied by 100). This therefore produces an output frequency F.sub.2 whose value differs from 300 KHz by 100 Hz.times.100 (or 10 KHz) when F.sub.1 differs from 10 MHz by 100 Hz. It is therefore a relatively simple matter to determine a 10 KHz difference in 300 KHz, by detecting the output of a filter and comparing this with a reference.
REFERENCES:
patent: 2666141 (1954-01-01), Clapp
Connell Peter P. R.
Yeomans Michael
RACAL-DANA Instruments, Ltd.
Tokar Michael J.
LandOfFree
Measurement of elapsed time for a predetermined frequency shift does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Measurement of elapsed time for a predetermined frequency shift, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Measurement of elapsed time for a predetermined frequency shift will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1576992