Hi Grant,I'm currently collecting parts for a vttc also. I'm going the 833C route. I spent a couple weeks searching the internet for new old stock (NOS), eBay, and misc. quotes from vendors. Phillip Slawinkski recommended Penta Labs. Well I learned that all new tubes are made in China these days (including Penta), but there is a possibility that you can find NOS around.
In the end, I found Penta an excellent vendor for the 833C's and the new tubes were priced about the same as what some eBay listings were wanting for old used tubes. Penta also provides a 13 month warranty on their tubes which is another nice benefit. The tubes were extremely well packaged.
Here's a look at one of the tubes I received. http://www.classictesla.com/vttc/833C001.JPGFor tubes, I think it's smart to simply pick up the phone and call the vendor to buy either new or NOS. I highly recommend Penta from my recent experience with them.
Take care, Bart Grant Visser wrote:
Hi all, Have been thoroughly enjoying my NST driven SG coil over the last few months (pushing 1.3/1.4 m sparks) and would now like to try my hand at a decently sized VTTC. The only tubes I have found locally so far are the 811A and 813A's. I have seen the 811A's mentioned quite a bit on the list but not a single mention of the 813A. To my heavily untrained eye the 813A looks like a great little tube (3 grids?) but thought I'd ask your advice before I go out and blow my non-existant budget. lol 813A: DC Plate Voltage = 2250V Plate Dissipation = 100W Datasheet: http://www.mif.pg.gda.pl/homepages/frank/sheets/079/8/813.pdf I'd like to push as much power as possible into a 160mm (6.3") coil at 300 to 350Khz, with dual or even quad tube configuration, staccato control and possible audio modulation. Best regards Grant _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla
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