Category Archives: Technology

Election hacking

A 2016 HBO documentary, Hacking Democracy, discusses voting irregularities and the ease of hacking the results of electronic voting systems:

It introduces Bev Harris, a 52 year old grandmother who stumbled upon evidence of vote tampering. She went on to create Black Box Voting, a nonpartisan investigative reporting and public education organization for elections.

Apparently these Diebold machines employ a Windows NT operating system.  Here’s an excerpt from a Security Analysis of the Diebold AccuVote-TS Voting Machine: “Simply put, many computer scientists doubt that paperless DREs [Direct Recording Electronic voting systems] can be made reliable and secure, and they expect that any failures of such systems would likely go undetected.”

Despite these problems, we believe that it is possible, at reasonable cost, to build a DRE-based voting system—including hardware, software, and election procedures—that is suitably secure and reliable. Such a system would require not only a voting machine designed with more care and attention to security, but also an array of safeguards, including a well-designed voter-verifiable paper audit trail system, random audits and forensic analyses, and truly independent security review.

In this video, Clint Curtis, a Florida-based computer programmer testifies to the U.S. House Judiciary Committee about vote tampering in software:

It’s much easier to audit a paper ballot system. Computers are faster than paper, but, to at least some degree, vulnerable to hacking.

Smartphones will track bus movements

Our county’s public transport authority promises that this Spring, county buses will report their real-time locations and estimated times of arrival. Read MyRide Broward – Broward County Transit’s Real Time Program.

By using MyRide to know when the next bus is going to arrive, you can minimize time spent waiting for a bus. You will know when to leave home or the office in order to meet the bus.

In addition to using the dedicated smartphone app, I hope that riders may use universal apps such as moovit to display arrival information.
The system sounds terrific.  According to its vendor,

ISR FleetTrack Passenger Information Software is a flexible system for the creation and broadcasting of transit related content to provide dynamic passenger information at stops, shelters, in-vehicle, terminals and any other point of presence such as:

At work or at home – real-time information via the Internet
On the way to the stop – real-time information via cellular phone
At the stop –real-time information on electronic display and by means of audio announcements
On the bus/in the tram – real-time information on electronic display

The information is transmitted from the ISR FleetTrack Server to the SPM (onboard computer) online via cellular communication, then passed on to the information display. This includes information such as:

Route – entire route path and destination stop is represented, not just the next stop.
Journey times – passenger knows how long his trip is predicted to take.
Transfer advice – informs the passenger of the possibilities for changing to different modes of transport.
Transfer times – indication of the next transfer times for buses, trams and trains simplify the journey for the passenger.

Features Include:

On-Board passenger voice enunciation such as current and next stop
External voice enunciation within bus stop and terminal
On-Board passenger route progression or intersecting routes display
Route and destination display on front and side bus signs
Passenger information displays at bus stops
Multi-Route display of next two bus arrivals

The system is being installed by Integrated Systems Research Corp., a company that’s headquartered in Israel. Their U.S. headquarters is in Baltimore, and they’ve opened an office near Fort Lauderdale. Also, Here’s ISR’s video:

I know nobody within the Broward County Transit Authority, so I’m just guessing based upon what I can find on the web. Apparently this kind of system is called an intelligent transportation systems (ITS). It appears that ISR’s ITS is a complete fleet management system that will include

  • improved bus maintenance scheduling
  • “CAD” (computer aided dispatch)
  • route planning
  • security.automated vehicle location (AVl)
  • real time passenger information (RTIS)
  • automatic passenger counters (APC)
  • automatic voice annunciators (AVA)
  • interactive voice response (IVR) systems

This system — if it works — could be terrific. We’ll see. If it succeeds here and elsewhere, it could help fix our transport mess.

The Victorians wired the world

Before the telephone, there was the telegraph. For the first time in history, messages could travel faster than a galloping horse and eventually they would cross continents and oceans. The information age began with the telegraph.

Here’s an excellent 1998 book with a similar theme: The Victorian Internet: The Remarkable Story of the Telegraph and the Nineteenth Century’s On-line Pioneers

Shortwave broadcasting is dying

I notice that many governments are cutting back if not shutting down their shortwave radio broadcasting operations. Shortwave radio and newspapers are both carriers of content, and both are affected by the Internet. Here’s a video from 2012 about Radio Netherlands closing its Caribbean shortwave broadcast station:

Putting all their eggs in one basket

I think that these broadcasters are shortsighted.

Providers of audio content argue that it’s cheaper to distribute their programming via the Internet. They forget that the Internet comprises many routers that reside in many countries. If a government decides to erect a firewall such as the Great Firewall of China, selected content can be blocked within that government’s jurisdiction.

One beauty of shortwave broadcasting is its simplicity. The entire shortwave route consists of only two stations: the transmitter and the receiver. Radio signals don’t respect national borders and radio jamming is expensive and never 100% effective.

In my opinion providers of other HF (high frequency: 2 to 30 MHz) services are also shortsighted, for the same reason: they’ve done away with their users’ backup systems. AT&T killed its high seas HF radiotelephone service, so now ships at sea depend solely on satellite links for shipboard telephone service. They have no backup. Ditto Loran-C: ships depend exclusively upon the GPS system for electronic navigation.


  • November, 2014: Does Shortwave Radio Have a Future?
  • August, 2010: Whatever Happened to Shortwave Radio?

    For all its transmission expense and audio problems, analog shortwave radio has one clear advantage over the Internet and domestic radio/TV: It cannot be easily blocked — even when states try to disrupt its signals using jamming transmitters.

    Webcasts can be filtered or blocked through IP geolocation techniques that block access to sites based upon the IP address of the site or the user.

John Lennon: Gimme Some Truth:

A 2000 year old computer

Nova: The 2000 Year-Old ComputerDecoding the Antikythera Mechanism (first aired on American PBS television network in 2013)

“It re-writes the history of technology.”


The Antikythera Mechanism Research Project

Jo Marchant explains: In search of lost time

Watch hard drives being made

Ever wonder how today’s hard drives are manufactured?  I think it’s amazing that we can buy hard drives that store more than a terabyte for about a hundred dollars. When you watch this video, you’ll see how this miracle in manufacture is done.

All operations are performed in a clean room environment, because clearances and tolerances are measured in fractions of microns. (A micron is about 0.00004 inch. A human hair ranges from about 20 to 150 microns in diameter.)  In operation, the read/write head of a modern hard drive flies a few nanometers above the platter surface.  A fingerprint on a platter could cause a head crash.

hard drive manufacture

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Assume nothing.

In the 1970s, I worked in west Africa on a variety of radio communication systems. One day I was told that the Nigerian Navy’s base in Calabar was unable to communicate with its ships at sea. Apparently their HF (high frequency, 2 to 30 MHz) kilowatt amplifier had failed. I was told nothing else about the problem.

Lack of detail was normal. Communication and travel then in most of Africa was difficult. I grabbed a Simpson 260 VOM (volt-ohm-milliammeter), a standing wave bridge, a small toolkit, service manuals, and headed to the airport. The 500 mile trip by air to Calabar went smoothly.

Nigerian Navy NNS Thunder
Nigerian Navy NNS Thunder
When I arrived at the Navy base, I was shown to the radio room, where new HF SSB (single sideband) transceivers and a kilowatt linear RF amplifier waited. The operators demonstrated low receive signal strengths and when they tried to transmit, the amplifier immediately turned off its output stage’s plate current high voltage power supply.

I removed the coaxial cable feedline from the final amplifier’s output connector and replaced it with a dummy load. The amplifier behaved normally. I measured the resistance to ground of the coaxial feedline’s center conductor; it was a few Ohms. This is not necessarily bad; antenna couplers and some antennas with a DC path to ground will display a low resistance to ground, but for most antennas, it indicates a problem with the feedline or antenna.

Check the simplest possible failure point first

I asked to see the antenna. We walked to a nearby field, and — guess what? The antenna was lying on the ground!

Problem solved, or at least we knew what was wrong. I wish that all problems were so easily solved.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

The Joy of Fix

Today I restored a neighbor’s mail program on his MacBook Pro. Both his IMAP and SMTP server name and port settings were incorrect. What had corrupted them? I don’t know. At least one “expert” had previously fiddled with this MacBook. After I restored its email function, the owner was elated.

It can feel delightful to fix systems and it was good to see the joy in my neighbor. Moreover, after solving server problems, it’s even better to see this joy in hundreds or thousands of users. It’s what keeps me in this biz.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Laser pioneer dies

Charles TownesCharles Townes, Nobel prize winner and inventor of the maser (microwave amplification by stimulated emission of radiation, 1953) and developer of the laser (light amplification by stimulated emission of radiation), died last week at the age of 99. Townes’ first maser in 1953 operated at the insanely high frequency of 24 GHz.

I admire Townes because he persisted in chasing his dream of using stimulated emission despite the discouragement of knowledgeable peers. The conventional wisdom of mid-twentieth century scientists was that yes, Einstein predicted stimulated emission, but we’d never be able to use it. We can thank Townes’ persistence and the solid state laser for giving us CDs, DVDs, and high speed data transmission over fiber optic cables.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Product documentation

I hadn’t thought about how poorly most consumer products are documented until last weekend’s experience with the Nextivity Cel-Fi “signal booster”. It’s a complex product, yet its documentation contains no technical detail. If I knew more about its inner workings and hidden mechanisms, I could more intelligently position its components.

Most consumer products lack real documentation

I’ve never worked for a consumer product manufacturer; I’ve worked only for manufacturers of military and commercial electronic equipment. The military requires explicit product documentation of almost every circuit element. Why? Because they usually provide their own product maintenance. Commercial customers may also demand explicit product documentation, but typically they’re content to rely upon third parties for product maintenance, so commercial customers demand less documentation.

There are exceptions to the consumer product scanty documentation rule: detailed shop manuals are available at a price from motor vehicle manufacturers. Also, a healthy aftermarket industry publishes repair manuals: Sams for consumer electronics; Chilton, Haynes, and others for motor vehicles.

Absent shop manuals, schematic diagrams, or printed theories of operation for most consumer products, we’ll just continue to fumble in the dark when they break or just need tweaking.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Cel-Fi LTE signal booster

T-mobile works fine for me, except in my house. I think that the nearest T-mobile cell site is about a half-mile away, but the signal path is filled with old growth (signal absorbent) trees. I can’t use my cell phone on the ground floor, and it’s usable in only a few spots on the second floor.

Neither T-mobile’s tech support people nor its store personnel have helped. I read that T-mobile is now providing “signal boosters” to customers with weak signals in their homes. Apparently AT&T and other carriers offer similar systems.

CelFi LTE booster from T-mobileOn Friday, I fetched a new T-mobile “Personal CellSpot 4G LTE Signal Booster” from the T-mobile store, after paying a $25 deposit.

My booster is the “Cel-Fi” model RS3 or DUO, manufactured by San Diego-based Nextivity. It consists of two small boxes — the window unit and the coverage unit — and their wall wart power supplies. The window unit receives T-mobile’s LTE or HSPA signal (presumably at 1700 MHz), demodulates it, and transports the data via a 5 GHz unlicensed UNI link to the coverage unit. I placed the window unit on the second floor and the coverage unit on the ground floor.

cel-fi system schematic in house

What is its theory of operation?

Apparently the system is essentially a repeater. I have no idea how completely it demodulates the tower’s signal before creating the in-house signal. Is the in-house signal that’s transmitted by the coverage unit on the same frequency as the tower’s signal that’s received by the window unit? I don’t know, but I doubt it. Nextivity merely states that the coverage unit “cleans up” (whatever that means) the signal. Neither unit has any user interface other than some front panel LEDs.

Does it work?

Placement of both units is critical. I needed about an hour to get the system working throughout my house. Without field strength measurement instruments, I relied upon the limited information that’s provided by the units’ front panel LEDs. It works.

I’ve found almost no technical information about this system except a bit in a thread on Howardforums and a press release regarding Nextivity’s use of 1/4 and 1/2 Watt output power amplifiers in this product. If you have technical information — especially antenna radiation patterns — on this product, please let us know.

What if it quits working?

Occasionally (maybe once a week) the received signal from the Coverage Unit drops to one bar and/or my phone reverts to a slow EDGE connection. I’ve found that resetting the Cel-Fi system restores signal strength and LTE speeds at my phone. Follow these steps, in sequence:

  1. Remove power to the Coverage Unit
  2. Remove power to the Window Unit
  3. Wait 30 seconds
  4. Restore power to the Window Unit
  5. Restore power to the Coverage Unit
  6. Wait a few minutes while the two units establish a good wireless link and the Coverage Unit adjusts its output level

You should eventually see a full 5 bars received signal strength at the phone.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Is radio and TV broadcasting doomed?

The FCC plans to meet with broadcasters with a view to recovering some radio frequency (RF) spectrum from them. Recovered spectrum would be auctioned to cellular wireless broadband Internet service providers.

From a spectral efficiency viewpoint, this could make sense. Today’s modulation methods conserve spectrum (compared to traditional AM and FM broadcast signals) and the cellular model allows many geographically separated users to independently share one frequency. The packet model leaves each channel available for others whenever data isn’t flowing. From a consumer’s point of view, it allows program content on demand, rather than only when the broadcaster airs the content.

I wonder how much longer the RF broadcast model will make sense?

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

Does car ownership have a future?

We’ve heard the mantra, “the Internet will change everything”, but did we think that it — together with smartphones — would threaten car ownership?

1914 Renault print advertisementVarious ride-sharing and car-sharing systems may be reducing the need for car ownership. Reuters recently published a detailed article titled Rise of the car-sharing apps poses threat to auto sector.

Another article titled Car Ownership Ditched as Flexible Travel Tech Upstarts like Uber and Blacklane Reshape the Industry recently appeared in England. It claims,

The car manufacturing industry recognises that this disruption is causing a trend away from car ownership and has invested in solutions that complement their automotive offerings.

Both articles report that the following ride-sharing and car-sharing service providers are expanding into global markets:
Cars stacked atop each other

  • Uber
  • Zipcar
  • Lyft
  • BlaBlaCar
  • Blacklane

The writers also mention investors who plan to create new ride-sharing and car-sharing services in major cities around the world. Maybe this is the end of growth for car manufacturing. Maybe it’s karma from the General Motors streetcar conspiracy of 1930 – 1960.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695

How mobile phones reveal your location

Obviously, when your phone’s GPS receiver is on, your location within 30 feet or so is usually available.

Cellular antenna system on monopole
photo Steve Kazella

There’s another way that remotes, your cellular service provider, 9-1-1 call centers [also known as Public Safety Answering Points (PSAPs)], and law enforcement can determine your phone’s location, even when your GPS is off, or even if your plain-Jane flip-phone has no GPS receiver. It’s called Uplink-Time Difference of Arrival U-TDOA). Here’s a brief simplified video description. Each cell tower has an antenna array with three or four 90 or 120 degree (when viewed from above) antenna sectors. Each tower knows, by comparing your phone’s received signal strength in each sector, which sector your phone is in. By measuring the propagation time for a “ping” to travel between the tower, your phone, and back again, it also knows the range to your phone. In a populated area your phone is likely to be talking with more than one tower, so all that’s needed is to know the bearing and range to your phone relative to two or more towers, and your location can be estimated within maybe a 100 foot radius. (You will be at the intersection of the two or more arcs.)

Even with only one tower talking to your phone, it knows that you are located somewhere along that 90 or 120 degree arc within the sector with the strongest signal. U-TDOA is used in Enhanced 9-1-1 Phase II systems so that first responders may be dispatched to wherever your cell phone is located when you place a 911 call for emergency assistance.

The only way to stop this is to remove the battery from your phone. (Oops. Sorry, iPhone users.) Switching it off won’t stop the communication. Switching it to Airplane Mode will prolly stop it, but there are no guarantees.

Update Here’s a clear explanation of mobile phone positioning techniques.

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© Russ Bellew · Fort Lauderdale, Florida, USA · phone 954 873-4695