Archive for the ‘Geekery’ Category.

Antivirus and Backups

A friend just asked, “Trying to do better with my computer. Just installed AVG for Mac and ran it. Is this a sufficient solution in terms of protecting from and eliminating malware? I’m all about easy. Thoughts?”

Here is my long winded answer:

I use Windows and all of my antivirus software is between my ears. If a website asks “Do you want to download or install xxxxx?” I think very long and hard about the people behind that request and what they have to lose. For example, Facebook won’t (overtly) screw you, they have too much to lose. But do you know who is behind the GetFreeStuffForFree! browser plugin?

Figuring out the business model of the company you are considering trusting is a good idea. Be very suspicious If the company looks to be giving everything away with nothing in return. They are getting something, or they wouldn’t be doing it.

Yes, AVG is a good idea. I also run the virus software that comes with Windows, Windows Defender.

You definitely should have your computer back up automatically online. Do this for a few reasons:
– your hard drive will fail some day, that is a certainty. Here’s an article I wrote in 2012 making that plea in more detail:
– If (when??) your computer does get hacked by some malware, a backup will save the day!
– If your computer is stolen or destroyed, a backup will save the day!
– Once you set it up, it’s automatic and EASY!

“But I don’t want to put my data online”

I hear that Time Machine is “the” app for local backups on Apple. If you don’t feel comfortable putting your files online, you can still get a lot of protection. I’ve recommended this in the past: Find 2 external drives (they cost <$80 at Staples) and a friend. Use Time Machine to back up your computer to the hard drive. Be sure to encrypt the backup (it's easy, see here: Give your friend the backup to keep in the back of their junk drawer. In 6 months, make another backup and trade hard drives with your friend. Can strangers break into your encrypted hard drive? If you use a 12 character or longer password (try the title of your 2 favorite songs or something similar), no. I couldn't find specific security information online about Time Machine but encryption with a long password is very secure. Harkening back to my last comment, Apple would have a LOT to lose if their encryption wasn't good. Oh and here's a funny/good password guide:

Pin to Start in Windows 10

You can pin a shortcut to the Start menu in Windows 10. Note that you can’t pin a document itself to the start menu, just a shortcut to it.

Here’s how:

To add Pin to Start to the context menu for a file, you will have to modify the Windows Registry. But first, create a system restore point!

Now, to add Pin to Start easily, copy-paste the following in a Notepad and save it as a .reg file:

Windows Registry Editor Version 5.00

; Created by TheWindowsClub [HKEY_CLASSES_ROOT\*\shellex\ContextMenuHandlers\PinToStartScreen] @=”{470C0EBD-5D73-4d58-9CED-E91E22E23282}”

Now click on the .reg file to add its contents to your registry. You will be asked for confirmation, so you may click Yes, to add it.


Thanks to  and

How to Read an EPUB on an Amazon Fire HD Using the Kindle App

I got a book in EPUB format and wanted to read it on my Amazon Fire HD 8 (5th Generation). It’s easy to do once you know the secret recipe:

  1. Get the free Calibre e-book management tool
  2. Use Calibre to convert your EPUB file to AZW3 format (the native Kindle ebook format)
  3. Connect your Amazon Fire to your computer with a USB cable
  4. Using the USB connection, find the folder named “Books” on your Amazon Fire HD
  5. Copy the AZW3 book file into the Books folder
  6. Open your Kindle app on your Amazon Fire HD
  7. Rejoice for the books are on your bookshelf!

Before figuring this out with the great help of my friend Michael, I tried several other methods unsuccessfully. See what doesn’t work.



Email Spam Proofing on Dreamhost with DKIM

Short form: Dreamhost showed me how to implement a method of decreasing spam at the domain level called SPF. They implemented another domain level method of reducing spam, DKIM, a few months after I showed them that they hadn’t set up their system properly.


Long Form:

Until recently, there was nothing stopping someone from sending email from illegitimately (called “spoofing” email). A lot of spammers used it to send junk email “from” This bothered me because:

  1. spam :-(
  2. Sometimes I’d get thousands of bounced emails
  3. It reduced the assurity that my domain wasn’t hosting spammers, so sometimes real emails I sent would be marked as spam

I talked to Dreamhost support and they showed me how to setup an SPF record for my domain. See here and here on how to do it yourself.

Dreamhost support also suggested I create the emails postmaster@ and abuse@ because “I have seen some cases even though they are very rare cases in which not having these emails set up can cause some problems with servers receiving email.” Ok, sure. So I set those addresses up.

I created an account at to periodically check if Gmail is getting any spam from my domain.

I read up on spam-proofing a domain and realized that Dreamhost hadn’t implemented DKIM. Actually, they set it up for my domain but it was left in test mode. Even in Dreamhost’s DKIM example the test flag was set (see “Example of a DKIM Record, they write: k=rsa; t=y; p=GIMfMA0G…). So I had several back and forths with Dreamhost tech support starting in February and yesterday I got an email, “Our devs finally got around to removing the test flag and now DKIM records are properly being served.” Hurray!

In conclusion, you might want to check the headers on your outgoing emails. Look for the “dkim” header. Previously, when my account was still in “test-mode”, headers looked like “dkim=pass (test mode)”. And now they look like “dkim=pass” :-)

I Fixed It

I’ve been thinking about a new phone because my battery isn’t holding a charge as well as it used to. When I found out that a new battery cost $5, I couldn’t, in good conscience, spend $450 on a new phone!

I was nervous about tearing my phone apart but it went exactly the way the video from and Gwendolyn Gay said. Mad props to them for making great tools and a great video that walked me through it. I also replaced the headphone jack that was filled with pocket lint.

Total cost: $5 battery, $8 headphone jack, $40 kit, 1.5 hours of my time.


PS. Midway through the repair, I had the patient lying on the kitchen table with all the screws and wires out. I thought “there is the money shot. Take a picture!” Then I remembered that I was looking down at my camera in 20 pieces.


I use a program to back up my computer online. It’s really good, it has saved me and Megan a couple times. Would you like to trade backup space? You backup your computer to me to me for free, I backup my computer to you for free. Message me.

Cloud storage hurmphyness and happiness

Cloud storage hurmphyness and happiness: Two years ago I got a free 48 gigs of space on Dropbox as part of a promotion. I’ve been using it to move photos, music, and files onto my phone. It’s great. The free promotion was expiring soon and I was loathe to spend the money on a full membership. Being the nerd I am, I spent some time setting up a do-it-yourself solution with ownCloud and Dreamhost. After several hours of fiddling, it still totally sucked. I think the reason was that ownCloud won’t run well on my shared hosting. But if I upgrade my Dreamhost membership, I’d be spending MORE than just getting the Dropbox upgrade. Hurumph. So I bailed on that and tried a couple other solutions. Well, today my Dropbox expired leaving me with a “measly” 6 gigabytes of free space. Hahah, That is exactly how much space I needed! They used to only give 2 gig of free space, which wouldn’t have been enough.

So, it’s back to life as normal.

Here’s a shout-out to Dropsync, the great Android app that works so smoothly on my phone to move files.


I just installed SSL security on Now you should always see a green padlock next to the address at the top of the page. I installed it with the help of Dreamhost and Let’s Encrypt, free SSL. I was worried something would break but it was pretty painless.

Protecting Children from Leaded Solder

In August, 2015, I wrote this policy for keeping children safe from lead poisoning in the electronics lab at The Crucible in Oakland, CA. It is a description of the problem, a well researched discussion, and a solution.

Here is the guide nicely formatted: Protecting Children from Leaded Solder at the Crucible


Protecting Children from Leaded Solder at The Crucible

Policy Statement:

Due to the potential of lead intoxication, it is the policy of The Crucible to not allow persons under age 18 to use solder that contains lead for electrical connections. Lead-free solder performs acceptably with far less possibility of toxicity.



This document is directed at multiple audiences:

– to the organization so they understand the additional expenses of maintaining a lead-free environment.

– to faculty so they understand the reasons for the shift away from an easier-to-work-with material.

– to parents so they understand how we are acting to protect children.


Solder is used with soldering irons in the Kinetics and Electronics department to make electrical connections. Solder composed of tin and lead is long established as a well performing product, but the dangers of working with lead are also well known. Even small amounts of ingested lead can cause irreversible neurological damage, especially in children. Large international efforts have been implemented to reduce human exposure to lead. Notably, leaded paint and gasoline were banned in the U.S. in the 1970’s, the European Union banned lead in all electronics in the 2000’s, and California’s Electronic Waste Recycling Act of 2003 bans lead in some electronics.


Leaded solder remains legal and commonly used for electronics in the United States. It is generally understood that when leaded solder is used with proper precautions, it does not constitute a danger to the user. However, younger students may have trouble following these precautions and may put themselves at risk.

Important dangers for children using lead solder are:

– The difficulty of enforcing strict hand washing policies in a classroom environment with children

– The relatively high incidence of pica (habitual eating of non-foods) among children and the difficulty of recognizing this practice in the classroom

– The possibility of careless handling of solder by children

– The extremely long-term toxic effects of lead poisoning

– The low dose needed to reach toxic levels


Lead-free solder is slightly harder to work with but the safety concerns far outweigh the time spent learning how to use the new material. Solder that is made with 96.5% tin, 3% silver, 0.5% copper is a popular substitute for leaded solder. Here is one vendor’s product: and another  Solder made from 99.4% tin, 0.6% copper works almost as well as the tin-silver-copper solder and is less expensive. Other types of lead-free solder are also available.

Costs of switching:  

Tin/lead solder costs about $25/lb, tin-silver-copper solder costs about $50/lb, tin-copper solder costs about $35/lb. Both lead-free solders wear out the tip of a soldering iron in 1/3 the time as with tin-lead solder. A new tip costs about $2-10.

A summer of classes typically goes through 1.5 lb of solder and 5 soldering tips. So switching to lead-free solder might cost an extra $50 in solder and $50 in tips.

Research on Leaded Solder:

“Lead poisoning has been reported in children after a single ingestion… Pica is a very well identified risk factor of lead intoxication in children.”

– Sabouraud, S et al. Lead poisoning following ingestion of pieces of lead roofing plates: pica-like behavior in an adult., 46 Clinical toxicology (Philadelphia, Pa.) 267–269 (2008).

In the Sabouraud et al. article above, a case study described a woman with a single 6mm bullet lodged in her body. Her blood lead level climbed to dangerous levels over a few months. This implies that if piece of lead-solder was lodged in a student’s stomach, the negative consequences could be dramatic.


(paraphrased) A 45 year-old woman had lead shot pellet lodged in her stomach, probably from eating a hunted animal. Her blood lead level climbed to 550 μg/L before she excreted the pellet. There are several similar medical case studies described in this article.

– “Intoxication from an Accidentally Ingested Lead Shot Retained in the Gastrointestinal Tract” Environ Health Perspect. 2005 Apr; 113(4): 491–493. Per Gustavsson and Lars Gerhardsson.!po=25.4717

“one study showed that about 10% of children older than 12 years engage in pica”

“Pica is observed most commonly in areas of low socioeconomic status and is more common in women (especially pregnant women) and in children. To our knowledge, the prevalence of pica is not known. Numerous complications of the disorder have been described, including iron-deficiency anemia, lead poisoning, and helminthic infestations.”

– “Pica: Common but Commonly Missed”

The CDC recognizes that “[n]o safe blood lead level in children has been identified” and that a blood lead level above 5 micrograms per deciliter (µg/dL) should be treated.

“…the average blood lead levels from 4 to 10 years had the strongest association with the adult full-scale IQ. For each 1 µg/dL average blood lead levels, the adult full-scale IQ deficit was about two IQ points.”


“Lead in the body comprises 2% in the blood (t1/2 35 days) and 95% in bone and dentine (t1/2 20–30 years). Blood lead may remain elevated for years after cessation from long exposure, due to redistribution from bone.”

– Gordon, J. N., Taylor, a., & Bennett, P. N. (2002). Lead poisoning: Case studies. British Journal of Clinical Pharmacology, 53(5), 451–458.

“Early symptoms of lead neurotoxicity in both adults and children include irritability, headache, decreased attention span, memory loss, and low-level cognitive impairment… As childhood exposure increases, behavioral symptoms of impulsiveness, inability to follow sequences or directions, decreased play activity, lowered IQ. and poor attentiveness are seen at PbBs of 10-35 µg/dL. …  Recent studies evaluating the relationship between blood lead levels and neurobehavioral performance have shown evidence of effect at levels below 10 µg/dL -the current level considered excessive for pediatric exposure… [In one study] a significant inverse relationship was observed between blood lead levels and reading and math test scores and comprehension testing. The correlation was noted at levels as low as 2.5 µg/dL.”

– Patrick, L. (2006). Lead Toxicity, A Review of the Literature. Part I: Exposure, Evaluation, and Treatment. Alternative Medicine Review, 11(1), 2-22.


A cursory review demonstrates that ingestion (accidental or otherwise) of even a single grain-of-rice sized piece of lead solder could be dangerous for a child. A grain of rice weighs about 0.01 grams. A 0.01 gram piece of 60/40 Tin/Lead solder has about 0.004 grams of lead. That could raise the blood lead level of a 50 kg child by 8 µg/dL, higher than the current proposed actionable level of 5 µg/dL. Accidental ingestion of piece of solder the size of a grain of rice is extremely plausible when a child eats their lunch in the same clothes they solder in.

Concerning the Dangers of Solder Flux:

Another potential danger to soldering are the fumes from the flux. People exposed to flux fumes for multiple years in the workplace have developed asthma-like symptoms. The danger to students appears to be very small owing to the short duration of exposure. Additionally, research on this topic continues to be inconclusive, even for people that have worked for many years with solder. No particular flux has been singled out as more toxic than another. As more research is found on this subject, the policy will be reviewed.


Research on Solder Flux:


“Research on the respiratory effect of exposure to solder fumes in electronics workers has been conducted since the 1970s, but has yielded inconsistent results. The aim of this meta-analysis was to clarify the potential association… Soldering may be a risk factor for wheeze, but may not be associated with a clinically significant impairment of lung function among electronics workers.”

– Mendy, A, et al (2011). Work-related respiratory symptoms and lung function among solderers in the electronics industry: a meta-analysis,


“A cross-sectional study was conducted in four medium-sized electronics firms in which control measures to capture solder flux fume were absent or visibly ineffective… The odds ratios for ‘all wheeze’, shortness of breath, and work-related eye, nose and chest symptoms were all significantly greater (raised about 4-5 fold) in women who soldered > or = 37 h/wk when compared with those soldering < or = 20 h/wk.”

– Palmer, K. (1997). Respiratory disease in workers exposed to colophony solder flux fumes: continuing health concerns.


Tips on Using Lead-free Solder in Place of Leaded Solder

Be sure to leave a small blob of solder on the tip when putting it down. Leaded solder only needs the tiniest bit on the tip to keep going, lead-free needs a larger blob, lest it oxidize fully.

Lead-free solder needs a higher temperature than leaded, typically 700-750F instead of 600-650F. A temperature-controlled iron works better than a cheaper current-controlled iron put to a higher setting. The higher setting will contribute to the tip wearing out faster, especially so with a current-controlled iron. Common tip failures include the tip becoming uncleanable after fully oxidizing, and the tip gradually being melted away.

Leaded flux-core solder adheres to dirty metal better than lead-free solder. Cleaning your piece with 98% isopropyl alcohol or other chemical wipes can help with adhesion.

Using finer gauge wire for lead-free may help. 0.031″ is popular for thru-hole and 0.023″ for surface mount.

Using deionized water in the cleaning sponge may help.

Lead-free solder wears out tips about 3 times faster than leaded solder. Be sure to have spare tips on hand.

Here is a guide to lead-free soldering from a major solder manufacturer:

Google Chrome Not Updating

Google Chrome Not Updating
I was having trouble with Google Chrome on a new computer. Chrome refused to update itself and I couldn’t make it update. Here is how I fixed it:

The problem turned out to be that Google Update (which maintains Chrome) had been installed on my computer by the manufacturer and wasn’t updating itself. There is no way to uninstall Google Update. To remove Google Update, remove all the dependent programs, wait an hour, and it will uninstall itself.

I uninstalled Google Toolbar for Internet Explorer and Google Chrome, waited an hour, saw Google Update was gone, reinstalled Chrome and TADA!