Breakdown Voltage Test

Yesterday, Kevin and I tested the model to make sure that the V/m did not exceed the breakdown voltage of air and the highest V/m measured was 115,000 which means there should be no arcing.

I also increased the number of tetrahedrals to the maximum allowed by the 8GB of memory to slightly more then 600K. Because the cavity is large, 15″ long and 11″ in diameter and is made up of round surfaces including the probes, it requires a large number of tetrahedrals. Unfortunately, it changed the results enough that the length needed to be modified in order for resonance to be achieved.

Because we are bumping into the maximum memory limit, I looked up the cost for adding another 2GB of memory for a total of 10GB. The best price I could find for a single 4GB memory stick is $187CND which would replace one of the four 2GB sticks already in the machine. The Kingston memory referenced is also vendor certified to work with the motherboard which is something we have had problems with before. Because our simulations are working and we can reduce the number of tetrahedrals if necessary, I have held off purchasing the extra memory.

I also got an acceptable quote for shipping the vacuum chamber from Orlando, Florida to Edmonton, Alberta for $220US from a UofA recommended carrier (Reimer/Roadway/YRC). For customs, because the cargo is freight and of a commercial nature, most brokerages require an account, which costs upwards of $200 just to create because of the paper work. I am going to attempt to do “self-clearance” by getting the paper work done myself.

As for the vacuum chamber, even though the price is only $57US when checked last, I have decided it is worth bidding $900 to win the cavity. I have done extensive searches online and through various databases, but for the size, nothing comes as close in price. Most cavities over 24″ square are $4K US or more. I still have not heard back from the seller about the inside dimensions though.

I won the vacuum pump for $222US (eBay link removed), which is about half of what it would have cost new ($390 – ). Shipping was $60 via UPS and I expect to pay $40 for customs and brokerage charges, plus I will replace the oil in the pump ( – JB is the brand of pump )

(While the simulations were running, I also helped Gary with fabricating his antenna. FYI – The link to the brazing propane torch is here: removed)