Jennings Vacuum Variable Capacitor 3KV 1000pf Collins p/n 635-5199-00 Tested #1 - $135 - (Anamosa, IA)
Jennings Vacuum Variable Capacitor, Made for Collins Radio Jennings p/n CMV1-1000-0103, Collins p/n 635-5199-00 (10 turns end to end) This was removed from a Collins Radio-Rockwell Collins HF antenna Tuner. Tested with a professional Capacitance Meter. I added a 1/2 inch fiberglass 1/4" diameter shaft to the gear to allow the average user more flexibility in using it. If you don't want the shaft, you should be able to remove it if you are careful. This vacuum cap has an additional characteristic that you need to know about. When turned fully counter-clockwise to the end stop, it will measure zero ohms across the capacitor. There are two ways to view this, #1 don't go to the end stop when turning counterclockwise. #2, if building your own automatic tuner, you can drive it gently to the far counterclockwise position to calibrate your equipment. I talked with a fellow Rockwell Collins Engineer that worked with these in HF Transmitters and he reflected that this was they way the these Jennings vacuum caps worked. FYI, I had 5 of these originally and the all acted the same way. Size: just under 1/75 inch diameter,main capacitor is 3.5 inches longend to end (shaft-end terminal) is 4.75 inches.the vacuum sealing stub out the front side is not included in the measurements This Vacuum Variable was originally used in a motorized automatic antenna tuner which is why it had a gear instead of a shaft. The last two pictures show the gear before the upgrade and the specially prepared fiberglass shaft that was used. The shaft was custom sized to be a tight fit into the gear, this aided in great alignment and added strength to the epoxy bond. Email if you have any questions Satisfaction Guarantee (buyer pays return shipping) Check out our Ebay store for other items we have for sale Shipping Charges: When we charge for shipping and handling fees, it is to cover some of the packaging and fees eBay and PayPal take out of shipping payments we receive. Return Policy-Satisfaction Guara…
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From ebay.com - 1 month ago