Original poster: Jim Lux <jimlux@xxxxxxxxxxxxx> At 08:11 PM 2/4/2007, you wrote:
Original poster: FIFTYGUY@xxxxxxxIn a message dated 2/4/07 12:56:03 A.M. Eastern Standard Time, tesla@xxxxxxxxxx writes:>As the fascinating tome on building your own lab gear ("Building >Laboratory Apparatus" by Moore, et al.) says:Interesting. This must be a later edition (2002?). My copy (copyright 1983) is actually "Building Scientific Apparatus" (shouldn't that be "Apparati"?).>"Don't build your own electron guns. They're a commodity item, and a >lot of time and money has been spent by the mfrs figuring out how to >make them."
I was paraphrasing (and reading in some of my own opinions, to be honest) the statement you quote below... Essentially that while one CAN build your own guns, you would probably be better off buying one already meade (e.g. from Cliftronics)
My 1983 edition has three pages on electron gun design specifically, in the chapter on "Charged-Particle Optics". Nonetheless, it says:"The design of multielectrode guns is a complicated process involving time-consuming experimentation. A number of special guns have been developed ... , and most can be constructed easily if they are really needed. In general, however, it is best to use the simplest device that will fulfill one's requirements. "The guns developed for TV tubes are the product of much industrial development ... Cathode-ray tube guns can be obtained quite inexpensively from commercial sources (such as Cliftronics) or from shops that specialize in rebuilding TV picture tubes."One wonders where to find a shop that rebuilds TV CRT's, 24 years after this information was published!
That might be a bit of a challenge...As it happens Cliftronics might no longer exist under that name.. There's a company called Video Display Corporation, Inc. who bought up a whole raft of such companies.. VDC appears to be in the remanufacturing of CRTs business and related areas, and, as such both uses and sells the componentry.
VDCs SEC filing says, in part, In 1989 the Company acquired the assets of Cliftronics, Inc., Vega Tronic, L.P., and a majority of the stock of Apex Electronics, Inc. Cliftronics and Vega Tronic assets and producton were moved to Tucson and the locations were closed. The Company later acquired 40% of Glowtronics PLC (Mysore, India) which was sold in Feburary 1995, and 48^ of Electrocanones de Mexico (Mexico City, Mexico) which was shut down in fiscal year 1994.
So it looks like there's a slowing demand for thse sort of things, and there's a big player out buying up the sources and closing them down, one by one. (The report says that the total sales of guns in 1996 was $660K) And, they say in the report that the company ceased direct marketing of TV grade electron guns to remanufacturers during FY1996...
So.. It looks like cutting open a tube is probably the best way to get an already made gun.
(There are companies like Kurt J. Lesker that probably sell guns.. and I see a references to Kimball Physics, Calabazas Creek Research, Ebeaminc.com, and Nonsequitur Technologies, Inc. as other sources.
But those are probably pretty pricey...
-Phil LaBudde