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If you want to build a high voltage low current supply in the 40kV-150kV range then here are some tips:

1) Don’t use a neon sign transformer or the 120V from your power outlet. The reason is that these are too low in frequency, and the latter is too low in voltage. The 60 Hz frequency means every second there will be 60 push-pull cycles on the multiplier, but the typical HV capacitors you can buy tend to lose their charge faster than that. This means the output will be pathetic and have deep ripples as the voltage can never maintain high levels consistently. Metaphorically it’s like an old car or lawnmower sputtering while trying to start up. Now, if you use large enough capacitors then yes you can get by with neon sign transformers, but cost and size of the capacitors become issues.

2) Use a flyback transformer instead. These run at 8kHz to 30Khz, way better than the 60Hz. That’s fast enough that the capacitors in the multiplier will stay charged up and the output remains relatively smooth and high in voltage. Then you can use 330pf, 1000pf, or 10nF high voltage capacitors and do just fine.

3) Make sure the flyback output is AC, not rectified DC. Some flybacks have diodes and smoothing capacitors built in. The problem then is that only the ripple component of that will offer a push-pull into the multiplier, and hence you will barely get anything out since the ripple is low. Note that if you place the ground wire near the output wire of a DC flyback it will generate a nice spark, but that doesnt mean it’s AC.

4) Use a ZVS driver if you want to efficiently power your flyback. These can be had for 15 bucks off eBay or aliexpress. You wind a center tapped winding on the flyback core with some insulated wire, anywhere from 5-center-5 turns (10 turns total) to 15-center-15 turns (30 turns total). That means three wires come out from this primary that you wind, which you insert into the corresponding ZVS screw terminals. The higher the number of turns, the lower the frequency and lower the voltage output of the flyback. This may be necessary to avoid blowing your diodes and capacitors.

5) Voltage output from the flyback can be gauged by measuring the spark length beween bare wire tips. It will be approximately 1kV per millimeter. So 1 centimeter = 10mm = 10kV. This is a very rough estimate. So if you wind 20 turns total and find that the voltage is around 12kV but you need 8kV, then reduce the output by winding a proportionately higher number of turns: take 20 times 12 divided by 8 = 30 turns (15 and 15).

6) Capacitors must be rated a little higher than the flyback voltage. So if the flyback outputs 15kV, then the capacitors should be rated 20kV or higher.

7) Diodes must be rated twice the flyback voltage. Thus if all you can find are 20kV diodes, the input must be 10kV or less. Or, you can put two diodes in series to bring that up to 40kV rating, twice a 20kV input. So for a 15kV input from the flyback, you can use 20kV capacitors and then two 20kV diodes in series. To double the current rating, put two diodes in parallel. Thus to double voltage and current rating, you should have two pairs of diodes (two in series, and then two of that in parallel = 4 diodes) instead of just one diode.

8) Use an output resistor to protect your diodes from too much current. If you short circuit your multiplier, or allow it to produce nice big sparks, then without a resistor you will get some very high current surges that will likely burn out one or more of your diodes. Get a high voltage resistor, 100Mohm to 500Mohms, 10 watts or higher. These can be bought off eBay or aliexpress. They look like long red sticks.

9) Stack your capacitors in parallel in the earlier stages. For the first 1/4 of your multiplier, it’s helpful to have higher capacitances. This helps build up more charge to power the rest of the multiplier more smothly. It allows for better load handling (less voltage reduction and ripple once a load is connected). So the very first two capacitors can be 3 or 4 in parallel, next stage 2 or 3, and next stage 2, and the rest 1. That is, if you can afford buying extra capacitor for that purpose. You can get by without doing this, but if you have caps to spare then it’s a good idea to parallel them up.

10) Use corn / canola / vegetable oil as an insulator instead of mineral oil. The properties of such oils is equal or better than mineral oil and it’s non-toxic, and potentially cheaper. That is, put your multiplier circuit in a tub or well-sealed (at the bottom at least) PVC or clear acrylic tube and fill it with oil. This prevents arcing that normally occurs in air, since oil has 3x the dielectric constant of air. Some people use paraffin wax with a few hot glue sticks dissolved in there to prevent shrinkage upon cooling, but a solid potting compound like this is a pain to remove if one of your diodes blows. Also, if an arc does form in oil, the oil is fluid and heals itself whereas a solid dielectric will have a little hole blown through where the arc went, encouraging further arcing.

11) Make sure your output resistor and beginning of the output cable are immersed in the oil too. The voltage prior to hitting the resistor is pretty high and has a tendency to arc over to ground if exposed to the air. So that part need to be in the oil. The upper half of the resistor doesn’t have to be, but if it fits under the oil then that’s better.

12) Use silicone as a sealant, not hot glue. Oil will dissolve hot glue. Silicone, the kind used on bathtubs and window sills, is a decent dielectric insulator and resists oil and breakdown from ozone and UV. Get the low odor formula if available.

13) If you need a low-ripple output, dual polarity (not just one polarity and ground, but -kV, +kV, and ground) and good load handling, then use a Villard Cascade instead of Cockroft Walton. It’s basically just two half-the-number-of-stages Cockroft-Walton multipliers that meet at their bases. So the flyback voltage feeds into the center of the circuit rather than the beginning. The advantage is that with half the number of stages per polarity, you get a better smoother output. The thing about Cockroft-Walton is that ripple and sag (from bad load handling) increases dramatically with the number of stages. Use half that number, and problems go away. So instead of 0 to 100kV, you get +50kV and -50kV but with a stronger smoother output voltage.

Here is how to move Apple’s Mail.app to an external drive or encrypted volume. This has been tested on Mavericks. Make backups before you attempt this in case something goes wrong.

Overview

You will need to move your mail folder to the drive, create a symbolic link to it, replace the original folder with the symbolic link, and enable spotlight indexing of that drive.

How to Do It

First quit Mail.app.

Download and install the Symbolic Link Maker service. This will add a context menu entry to create a symbolic link. You may need to restart/logout/login to complete installation.

Then make sure the volume/drive you’re moving the mail folder to is formatted as Mac OS Extended (Journaled). Let’s assume its volume name is MAILDRIVE, but you can name it anything.

Now copy your /Users/[username]]/Library/Mail folder to MAILDRIVE.

Then back in the original location, drag the mail folder out onto the desktop for now.

With the Mail folder copied over to the target drive/volume, right click (or CMD click) on the Mail folder, go down to “Services”, choose “make symbolic link.” It will create a symbolic link called “Mail symlink.”

Drag that symlink to the original mail folder location, and rename it simply “Mail”

So now the original folder has been moved and a redirect (symlink) put in its place that points to its new location.

Next, open up Terminal and enter: sudo mdutil -i on /Volumes/MAILDRIVE … enter your password when it asks. Then it should say after a few seconds that indexing has been enabled on MAILDRIVE. This will enable Spotlight indexing. Otherwise you won’t be able to search your mail messages.

So now you can open up Mail, and after Spotlight indexes the drive/volume you’ll be able to search messages and operate as before.

Notes

Yes, if your Mail folder is on an encrypted DMG or Truecrypt volume, Spotlight is a security risk. Weigh that before doing this. For example, it would be good enough to keep roommates and thievess from accessing your mail, but not some professional who combs through the Spotlight index and tries to piece together the contents of your emails.

What is borscht? It’s a red colored stew made with beets, originating in Ukraine but widely eaten in Russia. Somewhat sweet and sour, hearty, often meaty, sometimes smokey.

What are the benefits of borscht? In a nutshell it is full of vegetables but particularly beets, which help produce nitric oxide in your body, which helps dilate blood vessels and assist mitochondrial function. See this article for more.

My Ukrainian grandmother gave me the following recipe. Just kidding, I don’t have a grandma from Ukraine. However in experimenting with numerous borscht recipes, I have refined them into a single master borscht recipe that is easy to make and tastes delicious. Anyway here is the recipe:

Smokey Borscht

2-4 smoked sausages (like andouille or kielbasa) sliced into half inch discs
2 chicken quarters, skin on and bone in

3-4 medium sized red beets, cut into quarter inch cubes (frozen is okay too)
1 small red cabbage, shredded
1 red onion, chopped
1 Gala / Pink Lady apple, cubed

2 cups water
1/3 teaspoon salt
3 tbsp apple cider vinegar

Instructions:

Put water, salt, and chicken in a pot.

Then add the beets, cabbage, onions, sausage, and apples — in layers, and in that order.

Put a lid on, bring to boil, then reduce to a simmer and let that simmer for 30 minutes.

Then add the vinegar, mix it all up, and simmer another 30 minutes. Done.

Notes

Only 2 cups of water are used because the cabbage, apple, beets, and onion exude water as they cook. Too much water in the beginning and the borscht comes out bland and must be boiled down, which wastes energy. It’s better to keep things concentrated.

The layers ensure that the apple and sausage doesn’t get overcooked. After 30 minutes of simmering, however, it’s okay to mix everything up.

The vinegar is added after 30 minutes because if added in the beginning, the acid dries out the chicken. Doing that after the chicken’s already cooked doesn’t have this effect. Also useful to know if making adobo chicken (a Filipino dish).

The smoked nature of the sausage is a central ingredient and gives this dish character. Other types of meat or sausage just won’t do. The chicken is just there to add more protein and provide a meaty broth.

There is no garlic in this recipe as it interferes with the purity of the fruit/beet flavor. I’m a fan of garlic but not in this style of borscht.

Also no potatoes here, but they can be added if desired. I recommend one or two red potatoes, cubed. I try not to eat too many nightshade plants as the solanine toxin in them hits your mitochondria pretty hard, which subverts the purpose of the nitric oxide effect from the beets.

The apple is important — it adds extra sweetness, tartness, and a fruity aroma that gives the borscht direction. Apple cider provides further tartness and makes the apple aroma taste more sophisticated. The two together offset the plain sweetness of the beets, resulting in a complex sweet-n-sour dynamic. This tension is then plucked by the smokey flavor to produce a Slavic siren song of tastes.

Traditionally, borscht is eaten in a bowl with a dollop of sour cream added on top, with a side of crusty buttered bread. Bonus points if it’s sourdough rye bread. I have fond memories of my non-existent Ukrainian baba eating borscht this way.

Internet Service Providers are notorious for snooping on their customers, using automated monitoring of what you do online. They are more than happy to rat you out to law enforcement, government, and other corporations without search warrants because privacy laws have evaporated. Your search queries, browsing patterns, chat logs, and other online activity are tapped and used to build a profile of you, to assess your potential threat level and where you will be should you ever need to be taken in. Most of this monitoring happens at a local/regional level, therefore bypassing that level is the most effective way of restoring some of your privacy.

To do that, your computer must be connected to a remote trusted server via an encrypted connection (a ‘tunnel’) and from that point on everything you do, every site you visit, will appear as though it were coming from that server. Since lots of others are likewise using that server, it’s very difficult to sort what traffic comes from which specific individual. Your IP address (which identifies you on the net) remains hidden, and that server’s address is used instead. This is an oversimplification but it’s basically what happens.

One of the fastest, easiest, and cheapest privacy services is NordVPN, which for $5 per month (on a year plan) will accomplish precisely this. It lets you bypass firewalls, web filters, and prevents your local ISP from logging your online activities (logs that are otherwise forwarded to snoops). So check out NordVPN and see if it fits your needs.

One note, however. If you want even greater anonymity you must disable IPv6 (which is like a new secondary IP address) because Google uses your IPv6 address, and not just your regular IP (such as 123.456.7.8), to identify you and your location. For example, go to news.google.com and see if your location shows up on the right column as local news stories. IPv6 cloaking by NordVPN will be implemented in 2015. For now, if you are on OSX you can disable iPV6 via these instructions. Even if you don’t, you can still gain much from using a VPN service.