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Categories | Electronic Component Suppliers | International Crystal Manufacturing Company, Inc. Help

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W6LBV  Rating: 5/5 Jul 31, 2013 13:21  Send this review to a friend!
"International quality!"  Time owned: more than 12 months
In the 1960s and 70s, when Amateur Radio Service narrowband VHF/UHF FM and repeater communications were first being developed, today’s synthesized “rice rocket” transceivers had not yet been designed and marketed. The bulk of the early development work was done with surplus commercial two-way radio transceivers: Motorola, General Electric, RCA, E. F. Johnson, and others. Each of these non-synthesized radios required two quartz (frequency) crystals per operating channel, one for transmit and one for receive.

In those early growth times when crystals for newly-acquired radios needed to be ordered, everybody had a single response: “International Crystal Mfg. Corporation, 10 N. Lee, Oklahoma City.” Effectively, there was no serious second choice.

“ICM” had won the competition for several reasons. They had a big production facility, the majority of which was used for manufacturing the same kinds of crystals for commercial radio systems. ICM had the “crystal correlation data” (i.e., the manufacturing specifications) for just about every two-way commercial radio that had ever been produced. And they delivered a quality product, consistently. Of course it also helped that they stood by their products, seemingly unconditionally.

They could even handle special requests: “I want to inject the local oscillator on the opposite side of the received carrier from the normal injection location. Please cut my crystal accordingly.”

Today every two-way radio carries but a single frequency-determination crystal, to control its time base oscillator. The demand for specific channel operating crystals has all but vanished. But International can still do the job; over the past two decades I have ordered some crystals for old commercial radios. ICM turned them out as though the year was still 1972. One small niggle, however: in recent years it seems that more often than not the new crystals do not “net” on the operating channel with the trimmer capacitor in the center of its operating range, but rather more toward one end of the range or the other. A center-netting crystal is desirable so that when the crystal changes frequency very slightly as it “ages,” there is still useful range in the trimmer to bring it back to the correct frequency.

But, if that lack-of-netting condition ever proved to be a major problem, I could just send the crystal back to ICM, and they would take care of it. That’s “International quality.” 
Product is in production.
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