Jan 30, 2019

Jan - 30 2019 | By

– from last Week HomeWork: MICROBIT 


Additional notes

Notifications of new show notes and edits are tweeted at: twitter.com/ddhart.
– They’re tagged with #Zentech.
– When what’s said is unclear to me (or I’m unfamiliar with a topic) I tend to quote (” “) verbatim.
– Editor’s comments are delimited by < >

For a couple of months, the audio of today’s show is here. Recent shows are here.

The intro and outro music was by Pentatonix.


Note that there will not be a Zen Tech show on Feb 13 due to a membership drive.


Both Paul & Glenn were in the studio today.


Glenn started off talking about paying thru your bank. Zelle & Venmo are a couple of the more popular options. He’s been using Zelle thru Wells Fargo. A typical example is paying back a dinner companion at a restaurant where you want to split the bill — you pay your portion after the companion pays the entire bill. There is no fee for using Zelle. To send someone money you just need their email address or cell phone number.

Glenn also has an online bank where he wanted to use Zelle. He couldn’t use his email address at both banks so he tried using his cell phone number, but it came back saying it’s not a cell number. So he reversed things, using the cell number at Wells Fargo and the email at the online bank. That worked.

Paul said that in the US, there is no way to know for sure if a number is cellular if you’re using a MVNO (mobile virtual network operator) as your cellular service. A MVNO is a company that resells a service that comes from one of the major carriers (Version, AT&t, etc.). Glenn uses Pure Talk.

Glenn went on to say that Zelle transactions are nearly instantaneous. The recipient gets an email or text message when the transfer occurs. The transaction is irrevocable. Both parties have to have to subscribe to Zelle. Glenn said he doesn’t know of any bank that doesn’t use it.

This type of service is nothing new to Europeans. They’ve had Postbank and Gyro, interbank transfer systems, for a long time, Paul said. In Japan they don’t use checks, only interbank transfers.

Glenn reminded listeners that they can send email to the show hosts at zen at kvmr dot org.

Turning to the homework links at the top, Paul talked about the Raspberry Pi. The pi comes from the programming language Python developed approx. 15 or 18 years ago. It was named, in part, for Monty Python.

The Raspberry Pi is a tiny computer on a board that’s no more than a couple of inches square. It uses a 5 volt power supply and a micro USB connector. It has some LED lights to indicate what’s going on and an HDMI output to hook it up to your TV set. The USB port lets you hook up a mouse & keyboard. One of the models of the Pi (the 3B Paul thought) has wi-fi and Bluetooth.

Don’t buy this as a home computer, Paul cautioned. It’s primarily for the hobbyist. Nevertheless, it is the 3rd highest selling platform, behind the PC and all things by Apple.

The Pi is used in all sort of applications. Paul is using it to make a security camera and also a weather station. Weather sensors for humidity, temperature and air pressure are about $2 each, Paul said. The 3b is the model that has all the bells and whistles and costs about $32. <See the links at the top for more info.>

It has a short but sharp leaning curve. And once you develop something with the 3B you can take the micro SD card and put it into the Pi Zero, the low budget model. The Pi Zero will then do what the 3B did but with “less space”, smaller dimensions and fewer interfaces. The latest Pi Zero, which is about the size of a chewing gum stick, comes with wi-fi. Paul plans to use his Pi Zero to augment his Roomba vacuum cleaner.. The Roomba doesn’t have very much suction but it does have patience and is good for the dust bunnies under the bed, he said.

You can get a Pi starter kit on Amazon, Banggood or Aliexpress. You can choose which operating system to run on it. Most people use Linux in a form called Raspbian, a free version of Debian Linux. It’s a real learning experience and you do have to follow the instructions.

Talk turned to DJ’ing. Glenn said that music is not a big part of his life. He finds iTunes confusing and would have trouble with software that a DJ would use. Paul thought he could get comfortable with a free piece of software called Mixxx <see the link at the top> for the PC and Mac, but had no clue on how to proceed. <Mixxx was mentioned on the 8-26-15 show>.

The idea is to use 2 turntables, on the screen as I understand it. You cue up on one and play on the other. Mixxx reads your playlist from iTunes.

PCs and Macs have just one audio output (the speaker) but you “can get a cheap audio device and connect it to a headphone” so you’ll have 2 audio outputs — the headphone and the speaker. This is the very basic setup. You can buy a USB adapter that gives you a headphone jack. The computer will identify it as a second audio channel with a name something like “USB audio”.

So now you play from your playlist out of one side, to your speaker, and something else to the headphone. Mixxx can detect the beat of the music and you can change the pitch and the speed. If one song is 60 beats per minute and the other is 90, the software can alter one to coincide with the other. It was at this point that Paul got bogged down with all of the options and buttons in Mixxx. It’s a learning experience, he said. If you know how to mix with 2 physical turntables, you should have little trouble proceeding.

Mixxx supports Midi devices. And for $40 to $60 you can get a USB device that has “2 tiny rubber turntables” and “a couple of actual real physical sliders”. “So you’re interfacing with the software on the screen in such a way that it looks like the hardware the formal DJ would use”. Despite making all sorts of mistakes, Paul said he’s having a blast.

Glenn invited listeners to call in with their questions and comment at 530-265-9555. You’ll be put on hold and then attended to in the order of your call.

He then read the disclaimer:
The views expressed on this show are those of the speakers only and not necessarily those of KVMR, our board, staff, volunteers or contributors.

Paul talked about WMA office. <See the link at the top>. This is, apparently, an office suite that, to a degree, mimics Microsoft Office. But it doesn’t come with Arial, Verdana and a couple of other fonts. They are under Microsoft license but can be downloaded for free. <See the link at the top>.

Bitstream & Adobe are companies that digitize fonts and they collaborated, with other companies to standardize the TrueType fonts specification. There are a huge number of free fonts.

If you type something in one font and send the document to someone, they may not have that font. The TrueType font file has information in it that allows automatic substitution of another similar font for the missing font. But it still may look a little different. That’s why people started using the .pdf document format. The .pdf would render the fonts as dots <essentially a picture>.

The Microsoft Word program has a way of embedding the definition of a font within the document. So if the recipient doesn’t have the correct font, the one in the document will be used.

All major platforms now use TrueType fonts, including Linux. But you’ll have to download Arial and Verdana separately.

Paul mentioned an interesting documentary about the Helvetica font and the influence a font can have on society in general.

Neil called. He had bought some rechargeable nicad batteries but they don’t work in his cordless phone. But they do work in a flashlight. If he replaces just one battery in the phone, it works
– Maybe the contact points are the problem. Use an emery board on the contacts.
– It’s not a good idea to mix batteries as Neil did. The stronger battery might dump the current into the weaker one and cause corrosion or make it over heat.
– Look closely at the contact points to be sure they’re connecting. There may be a physical difference between the original & replacement battery.
– Get a cheap battery tester. The tester should put small load on the battery. A multimeter is designed not to load the battery.

Steve called. He uses a popular CAD program (Computer Aided Design). He’s seen older versions for sale on the internet from dealers who aren’t authorized to sell them. They buy the software from a abroad and sell it in the US. He wants to know if it’s legal software.

If you buy software that comes with a key and you can successfully activate it using the key, the odds are high that it’s legitimate software. If it doesn’t activate, ask for your money back. Some software may get hacked so it doesn’t need activation. Some may have had the key stolen from a school or college that was using what’s called a VLK (volume licensing). Some software may be so old that it isn’t rigorous about how it activates (it may not connect with the company over the internet to confirm).

If you really want to know if the software is legit, communicate the company and ask if the key is legitimate.

If someone bought software and later decided to sell it or move it from one machine to another, the key should be deactivated. The license can then be transferred. If a reseller is involved, you’re in a gray area.

You don’t actually own the software, just the license to use it. And there’s the question of whether it’s the person who owns the license or the machine.

Glenn opined that there isn’t much in open source CAD software. As soon as he said that, Paul found Freecad. But it seemed that wasn’t an option for Steve, he needs compatibility with the software he’s now using.

Another option might be to buy an older version of software legitimately, and then use it as an upgrade path to get a newer version. Of course, first check that the upgrade is available.

Doug called about Neil’s battery problem. He suggested that the cordless phone may not have been designed for nicad batteries. Be sure the replacement batteries are of same type. Some devices may have a switch to select for the type of battery you’re about to put in.

Paul called. He wants to get a simple phone, not a smartphone, for his disabled son. Are there free phones for those on SSI, he wondered.
– Do a Google search but beware of scams.
– Call the social service you use or a county social worker to find out what’s available.
Tracfones are cheap.

Last Updated 12:45 AM 1-31-2019

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