UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Fascinating Documentary about Quartz crystal manufacturing

Bazz4CQJ · 19th Nov 2017, 5:44 am

Those crystals look to be the same size as those fitted in the smaller FT243 holders which were in such great demand during the Golden Age of 2m AM ~1970. There were just a few crystals of around 6MHz and 8MHz that would multiply up the the upper end of the 2m band, of which the 8.100MHz was most common. I recal taking some of those crystals and abrading them with "Vim" scouring powder to raise their frequency just a little to escape QRM with other people owning 8.100's.

What surprises me about that film is the very cursory way the crystals were dried, using only a brief blast of compressed air, after coming out of the etching solutions. After scouring and washing, we always baked them dry in the belief that activity and stabilty demanded this.

I wonder what the X-ray "remediation process" was suppose to do?

I wonder if that war-time film represents the truth, the whole truth and nothing but the truth?

B

19th Nov 2017, 5:44 am	#2
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,935	Re: Fascinating Documentary about Quartz crystal manufacturing Those crystals look to be the same size as those fitted in the smaller FT243 holders which were in such great demand during the Golden Age of 2m AM ~1970. There were just a few crystals of around 6MHz and 8MHz that would multiply up the the upper end of the 2m band, of which the 8.100MHz was most common. I recal taking some of those crystals and abrading them with "Vim" scouring powder to raise their frequency just a little to escape QRM with other people owning 8.100's. What surprises me about that film is the very cursory way the crystals were dried, using only a brief blast of compressed air, after coming out of the etching solutions. After scouring and washing, we always baked them dry in the belief that activity and stabilty demanded this. I wonder what the X-ray "remediation process" was suppose to do? I wonder if that war-time film represents the truth, the whole truth and nothing but the truth? B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch.