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Old 08-05-2015, 3:31 PM
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ko6jw_2 ko6jw_2 is offline
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Join Date: May 2008
Location: Santa Ynez, CA
Posts: 596
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Commercial crystal receivers had netting trimmers to precisely adjust the oscillator using the discriminator test point. Only a tiny number of consumer scanners offered this feature. The problem is that the tolerances for receiving crystals were not very tight. I remember returning crystals to me local radio distributor many times until I got one that worked. The IF is not the only parameter to be concerned with. Most scanner crystals were 3rd overtone mode plus or minus the IF frequency. It is important to have the correct design if the crystal is to work properly.
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