What is going to be the stability of your 4.9512 clock you will be using as reference frequency? It better be really good. I'm guessing your counter may have a more stable reference frequency built in to it already, probably 10 MHz?or something like that. The absolute calibration of the counter is not so important for crystal matching, stability is. If your counter will read frequency to 10 Hz or better I would just go with reading frequency, even it it is not perfectly accurate. Again for matching you are comparing the frequencies, not measuring them exactly to a traceable standard.?
73/72 - Mike WA8BXN
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[email protected]Subject: [qrp-tech] Frequency Counters for Matching Crystals
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I have an HP 3283a frequency counter that will allow a reference frequency to be supplied at its back panel.? If I choose to drive it with a 4.9152 MHz clock I can sample a DUT crystal and read the display as a ratio of the DUT to the reference.? At a sample interval of 0.1s the ratio is exactly an order of magnitude greater than the actual ratio, i.e. 10x.? Wouldn't that be better than a direct frequency reading for purpose of frequency matching?? Has anyone tried the ratio method with success?
Howard, n3fel
