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FRIDAY - APRIL 4, 2003 - ISSUE NO. 60

Dear Friends and Industry Colleagues,

I had several very good responses to last week's newsletter, especially on the new TECH TIPS section with the information about the ReFLEX25™ paging protocol. Clarifications have been added this week, with some new information about ReFLEX50. Following, there are some excellent reader's comments on how ReFLEX25 and ReFLEX50 merge together in the latest release of the ReFLEX 2.7.x specification.

This is my weekly newsletter about Wireless Data and Radio Paging. You are receiving this message because you have either communicated with me in the past about a wireless topic, or your address was included in another e-mail that I received on the same subject. This is not a SPAM. If you have received this message in error, or you are not interested in these topics, please click here, then click on “send” and you will be promptly removed from the mailing list with my apologies.

Lots of e-mail came in this week from places like Europe, Africa, South America, Central America, New Zealand, Mexico, and the Middle East. It is comforting to know that there are people all over the world still working with paging and even planning to build several new systems. I can't imagine why anyone thinks paging will die and go away when a paging system costs a small fraction of the cost of a cell phone system. The simple facts are these: paging technology offers the most cost-effective and reliable form of wireless communication that we have in the world today.

I hope you enjoy this week's issue. Comments and suggestions are always appreciated.


Navstar GPS satellite launched

April 01, 2003 12:50 PM EST

CAPE CANAVERAL, Fla.—The Navstar GPS 2R-9 satellite was launched from Cape Canaveral Air Force Station this week.

The new satellite joins the constellation of 27 GPS satellites that orbit 12,700 miles above Earth. GPS satellites, which both military and civilians use for navigation purposes, play a critical role in the war in Iraq, guiding precision weapons to their targets.

Source: RCR Wireless News

Disposable Cell Phones

How Disposable Cell Phones Work

disposable cell phone

A credit-card-size disposable cell phone will offer an approximately one hour of talk time.



There are few places you can go today without having some mode of communication to stay in touch with what's going on at home or work. Mobile devices, such as cell phones, allow us a connectivity that wasn't possible 20 years ago. Yet, these marvels of modern telecommunications can deliver headaches when they don't work properly or if you wander beyond the range of a cell tower. It's enough to make you want to throw your cell phone in the garbage can. Soon, you will be able to do just that.

Randi Altschul, a New Jersey toy designer, has invented the world's first truly disposable cell phone. Most cell phones end up on the trash heap after a few years anyway. Altschul's phone is the first that can be bought, used once and then chucked in the trash.

Cell Phone Construction

insides of disposable cell phone

The disposable cell phone's architecture is very simple. Circuitry is formed by printing metallic inks on to a paper substrate.

The 2- by 3-inch (5.08 X 7.62 cm) phone is made by printing cell-phone circuitry onto a paper substrate, which is then sealed and laminated. We'll take a look at this novel invention and it's remarkably simple manufacturing process.

Basic Manufacturing Process
If you were to crack open a conventional cell phone, you would find a circuit board and other components, such as a speaker and microphone. All of the circuits are made of tiny metallic wiring that connect the various microprocessors, the speaker and the microphone. A disposable cell phone has basically the same configuration, except metallic inks are used instead of real wires. This ink is printed onto the substrate, and then other components are inserted into or fixed to the substrate surface.

Source: Verizon Learning Center

Glenayre to Appeal Infringement Verdict

Atlanta, GA—April 2, 2003 - Glenayre Technologies Inc. announced today that a jury of the federal district court in Chicago, Illinois ruled in favor of Philip Jackson in his patent infringement suit against Glenayre and awarded damages of $12 million.

"We are obviously very disappointed in this verdict, as we believe the evidence does not support the jury’s finding." commented Eric Doggett, president and chief executive officer of Glenayre. "Glenayre will appeal the verdict and we believe we have strong bases for having both the finding of infringement and the damages award overturned."

Source: Glenayre web site

Philip Jackson sued Glenayre claiming that they infringed on his patent for an interactive telephone answering system.

Can You Hear Me Now?

April 3, 2003

Another milestone was marked today in the cellular telecommunications industry. The first public telephone call using a portable cellular phone was made on April 3 in 1973.

Marty Cooper, now chairman and CEO of ArrayComm, made the first call when he was general manager of Motorola's Communications Systems Division. Cooper made the call from a street in New York City to AT&T Bell Labs.

"As I walked down the street while talking on the phone, sophisticated New Yorkers gaped at the sight of someone actually moving around while making a phone call," Cooper recalled. "Remember that in 1973, there weren't cordless telephones, let alone cellular phones. I made numerous calls, including one where I crossed the street while talking to a New York radio reporter-probably one of the more dangerous things I have ever done in my life."

It wasn't until 10 years later that Motorola started selling the first commercial cell phone, the DynaTAC.

Source: Wireless Week

My little part in cell phone history was to make the first cellular telephone call in Puerto Rico, about ten years later while demonstrating the DynaTAC cell phone in San Juan. I called Caesar Silva, a Motorola salesman who worked for me at the time, using a DynaTAC "brick" and a special cellular base station which had been stuffed into an aluminum suitcase to make it portable.


Missing Materials

For a long time I have had a link on my web site to an excellent paper: An Introduction To Paging—What It Is And How It Works, by: A.S. Hon—Motorola, Singapore. Unfortunately Motorola has removed this valuable resource from their web site. It was also available in a printed booklet at one time. Does anyone know where I can get a copy? Maybe someone has a soft copy of the web article that I could put on my web site. How about you guys in Singapore, do you know where A.S. Hon is these days? He doesn't work for Motorola anymore. Maybe he can send me a copy.

Also, Paul Cassel is looking for a copy of: Comprehensive Guide to Paging that was printed in early 90s. Can you help him out?

Paul Cassel
Telephone: 519-634-5139


ReFLEX™ tutorial continued

Following is some excellent supplementary information on ReFLEX. Several readers sent in additional information and positive comments on last week's TECH TIPS. We are fortunate that some of the industry's leading engineers, who work with these issues on a daily basis, have taken the time to contribute—for the better understanding of us all. I haven't included their names since I want them all to feel free to send in more comments in the future.

The information on ReFLEX last week was all about ReFLEX25 since that is what I am most familiar with. I should have pointed out some of the main differences between ReFLEX25 and ReFLEX50, but I have to be careful because both of these protocols are proprietary to Motorola and Motorola/SkyTel respectively. So, I am only reporting details that I believe to be public information. I think both names, "ReFLEX25" and "ReFLEX50" were unfortunate choices. They should have been called "ReFLEX 12.5" and "ReFLEX 10" which more correctly describe their basic differences. In other words, ReFLEX25 uses 12.5 kHz channel spacing and ReFLEX50 uses 10 kHz channel spacing. Following are some clarifications to last week's information as adapted from an e-mail sent by an authority on ReFLEX who was kind enough to check my work:

Forward channel options:
Reverse channel options:
2-level FSK @ 1600 bps4-level FSK @ 800 bps
2-level FSK @ 3200 bps4-level FSK @ 1600 bps
4-level FSK @ 3200 bps4-level FSK @ 6400 bps
4-level FSK @ 6400 bps4-level FSK @ 9600 bps

Like FLEX, ReFLEX25 can operate using the same three forward channel rates and two types of modulation. A difference between FLEX and ReFLEX, however, is that the maximum FLEX deviations are ±4800 Hz from the center frequency, while, as shown last week, the ReFLEX maximum deviations are ±2400 Hz. Because of these narrower deviations, three ReFLEX channels will fit within the NBPCS mask—also shown last week. FLEX and ReFLEX both use the same interleaved (31,21,2) BCH coding*.

The reverse channel maximum deviations are the same as those of the forward channel: ±2400 Hz from the center frequency. The error correction on the reverse channel uses a shortened (31,23) Reed-Solomon code*.

The reverse channels for ReFLEX50 are very similar to ReFLEX25, however, there are some differences. I can't say too much about ReFLEX50 because it is proprietary to SkyTel and I have never had access to the details.

* Bose-Chauhuri-Hochquenghem (BCH) and Reed-Solomon (RS) are mathematical error detection/correction codes used in wireless data communications.

Another reader had this to say:

I thought your tutorial on ReFLEX was great. I would like to recommend a follow-up article to cover the aspects of ReFLEX 2.7 especially that ReFLEX also supports 9600 [bps] on the reverse path, and 4 sub-channels @ 10kHz spacing in a 50kHz forward path channel. We have moved past ReFLEX 50 and ReFLEX 25 to ReFLEX 2.7 which merged the two versions. Maybe this should be noted in the next newsletter [so] the device manufactures [can understand that] they must support ReFLEX 2.7 with the different channel spacing and speeds.

Maybe someone would like to volunteer to write a summary of the features of ReFLEX 2.7.x that I could publish in a future issue of the newsletter?


Your ReFLEX charts were great.  Don't forget the 10 kHz mode for ReFLEX 2.7, where we pack four 10 kHz subcarriers into one 50 kHz channel.  This is the "Skytel" mode of operation.  All 2.7 devices, as well as the Advantra "Barran" and "Karli Lite" products, can seamlessly switch between 10 kHz and 12.5 kHz channels.

And another:

I enjoyed reading your ReFLEX for the non-engineer article. One point of clarification or amplification I would like to bring to your attention is that on the forward channel the modulation speed is not fixed at 6400 bps as your article tends to indicate. You can operate a ReFLEX25 channel on the same speed increments as you can a FLEX channel.  Therefore, your forward channel speeds could be 1600, 3200, or 6400 bps.  Just a point of clarification, but I certainly believe you hit most of the high spots on ReFLEX for those folks that don't work with this day in and day out.

One other point, the reason that the FCC has dubbed the spectrum narrow band PCS is because the individual channel segments or what you call sub-channels are much narrower than a traditional paging channel.  A traditional paging channel or any of the 2way radio channels authorized in Part 90 of the FCC rules are allowed to operate on a 25 KHz channel spacing. This contrasts with either 12.5 or 10 KHz channel spacings for ReFLEX hence the connotation of narrow band. Since you are referring to ReFLEX 25 I will stick to that for now. Using ReFLEX 2.6 protocol the channel spacing on the forward channel is 12.5 KHz thereby giving you the ability to only have 3 carriers on the forward channel in a 50 KHz channel slice. However, ReFLEX 2.7 changes the bandwidth assignment to allow flexibility between ReFLEX25 and ReFLEX50 systems. The network operator can set his system up to either support 12.5 or 10 KHz channel spacing on the forward channels with all the reverse channels still operating on a 10 KHz basis. Essentially, a ReFLEX 25 network operator could get an additional channel or 25% additional channel capacity by utilizing ReFLEX 2.7 protocol and having 2.7 devices. If there are legacy 2.6 devices on the network, the 2.7 devices are backward compatible with the 2.6 protocol, but a 2.6 device cannot operate on a 2.7 system.

Again, I enjoyed the article keep of the good work.

Baud, bits-per-second, and symbols-per-second are not all the same as the link to the left will tell you. Would someone volunteer to write a brief, not-too-technical article explaining what these terms really mean as they are related to paging and wireless data? I think this would help in our understanding of 2 and 4-level modulation and different paging "speeds."




vytel logo


ptx-150 image


Specifications and Features

User's Manual

To request pricing and delivery information for the PTX-150, please click here. left arrow

animated wireless logo Wireless Data

I am a manufacturer representative (MR) for Vytek Wireless Products. (Formerly Sonik.) Please look at their web site to see what they have to offer to the Paging and Wireless Messaging industry.

To download the product brochure for the PL-900 Paging Data Receiver, please click here. left arrow left arrow CLICK FOR MORE INFO

To let me know if you would like to receive a price quotation on any Vytek product, click on the link above.

aapc logojoin aapc

AAPC’s Mission Statement Defines Purpose

  • Identifying issues of common concern to its members
  • Providing an effective forum for the discussion and progression of issues relating to the industry
  • Monitoring and addressing regulatory and legal matters as a unified organization
  • Providing research into and development of our industry and its current and prospective markets
  • Providing education and resources to address the challenges and trends affecting our operating environments
  • Encouraging and maintaining high standards of ethics and services
  • Championing the industry and representing paging carriers with a positive voice

Our industry must move forward together or perish individually. If you want to get involved, please click here. Come and join us!

tga logosparkgap photo

Two-way Paging Network and Transmitter Controller

TGA Technologies believes that the future of the radio paging industry lies in the evolution of 2-way paging for both man and machine, based on the ReFLEX™ format. To that end, TGA has produced the SPARKGAP™ ReFLEX Network Manager. This device is fully ReFLEX 2.7.x compliant and will support campus, local, regional or national networks.  When used in conjunction with the TGA PRISM paging terminal, SPARKGAP™ offers a controlled path for growth in paging technology.

They also have a new product that can replace the RTS Advantage™ that many international paging network members are using.

I completely agree with TGA's strategy. If you would like to have more information about the SPARKGAP™ click here.

Can You Help?

news stream imageAs we all know, Wireless Messaging is less than 20 years old yet it is almost impossible to find evidence of our early experiments and successes.  Many of us experimented with wireless delivery of e-mail using the Teknow solution from the late 80s and others wrote simple scripts to parse and send SMTP messages to our pagers.  However how many of us documented these experiments?

Before what is left goes to the landfill, or is lost as us old timers start to die off, I would request help in archiving the following into a Museum of Early Messaging.  It appears that support to house this museum may be forthcoming from a pioneering company in Wireless Messaging but nothing is firm at this point.

  • Articles or papers on early 90s use of a browser on a two-way wireless device (Newton etc.)
  • Description of Anterior Technologies / RadioMail (pre Motorola) messaging Gateway and PDA/paging solutions.  Any magazine articles or early brochures on RadioMail would be very helpful.
  • Documentation and HP95LX software for the Motorola NewsStream module. Any articles on examples of uses would be great.
  • Any documentation magazine articles on the use of delivery of e-mail to a wireless device.
  • Back issues of Telocator Magazine from 1990-1995 time frame.
  • Motorola PCMCIA PagerCard with documentation and PC or PDA software.  Any articles depicting early use of the card also helpful.
  • Comprehensive Guide to Paging that was printed in early 90s.

If you think you can help with any of the above I am prepared to cover all hard costs as well as compensate fairly for any old hardware offered to the cause.  

Can you help? Give me a call or e-mail.

Paul Cassel
Telephone: 519-634-5139

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Cell Phones

I owe everyone who asked for my list of cell phones for sale, a big apology. I am very sorry but my source of this equipment has temporarily disappeared. The fellow I work with said his computer died and he had to buy a new one. I haven't been able to talk to him in over a week. Maybe I will have to stick to paging and wireless data. I am very sorry; this was beyond my control.

Needed, one LS350 Motorola pager programmer.
Contact Glenn Varen.

In need of Motorola BR-850s pagers—looking for new, refurbished or A stock.
Contact Ralph LoPilato.

Legacy Technology Solutions LLC

Paging infrastructure repair with warranty. Please ask for Virgil Jarrard, President, and tell him Brad sent you. Toll-free voice: 1-877-436-8044 or voice: 972-436-8044, fax: 972-436-8944. They are located in the Dallas suburbs, and they occasionally have some good deals on reconditioned paging equipment as well. Check with them for current product availability. You can send Virgil an e-mail by clicking here. left arrowCLICK

The PTX-150 VHF Direct Digital Paging Transmitter is designed to meet the paging industry’s latest standards for high-speed FLEX and simulcast operation. It operates with a wide range of standard network interfaces, and is ideal for both new systems as well as upgrading of existing paging networks.

This Direct Digital Paging Transmitter is designed to generate all modern paging formats including POCSAG, FLEX and ERMES. Standard output power is 100 watts continuous (adjustable 25-100 Watts). Optional amplifiers are available with 250 and 500 Watts output. Up to sixteen channels can be preset for multichannel operation over the 138-174 MHz frequency range.

For simulcast operation the standard internal 1 ppm TCXO may be supplemented by either a built-in 0.05 ppm high stability option or an external reference oscillator. Precision control over carrier offset and delay equalization is also provided.

The PTX-150 incorporates a wide variety of network interface and remote diagnostic capabilities. The standard unit includes an interface for conventional POCSAG controllers and paging terminals. It also includes an interface for C2000 and C-Net controllers. A separate data port provides comprehensive local or remote programming, real time diagnostics, and alarms for all key operational parameters. A WINDOWS®-based software package is available to provide a convenient and easy-to-use remote monitoring capability.

The PTX-150 is ultra-efficient in operation and incorporates a built-in universal 115/230 VAC power supply (auto select) 50/60 Hz. It is supplied in a compact 4 RU high rack mounted case and includes internal front to back cooling optimized to maintain low PA junction temperatures. The unit is rated for 100% continuous duty at up to 60° C ambient temperature.

VYTEK's PL-900 Paging Data Receiver

paging data receiver

Wireless Data—breathing new life into the paging industry. The Daviscomms TMR (Telemetry Messaging Receiver) is a one-way FLEX™ telemetry device and is being manufactured by Daviscomms in Singapore. It is being stocked and distributed in the Americas by Vytek Wireless Products as the PageLink™ PDR (Paging Data Receiver). The PL-900 provides a solution for customers looking for a CreataLink™ one-way receiver replacement. THIS IS A HOT PRODUCT.

Do you have a product or service that you would like to promote in this newsletter?

If you have any wireless equipment that you would like to buy or sell, please let me know. I don't charge individuals for listing something for sale. If a sale is made through this newsletter, I ask the seller to send me a 10% commission, much the same as the voluntary payments that are requested on the Internet for shareware. There is no cost to the buyer.

There is a small charge for companies wanting to put their products in the newsletter and on my web site. There is no obligation for payment of a commission for this kind of basic advertising. I would be very pleased, however, to get involved in the sales process as a manufacturer representative—for quality wireless products and reputable companies. left arrow CLICK FOR MORE INFO

Wireless Messaging Software

InfoRad® Wireless Office (Windows 95, 98, ME, NT, 2000, XP) is designed for the professional who needs full-featured wireless messaging capabilities. Features include enhanced user interface,  message log with search function, scheduled paging,  group and individual message addresses, TAPI Smart™, multiple protocol SMS communication compatibility. AlphaCare™ support services available. With a 32-bit architecture, InfoRad Wireless Office is designed for compatibility with Windows 95/98/ME/NT/2000/XP. For more information on InfoRad Wireless Messaging software, and a free demo, please click on the logo.

InfoRad logo left arrow CLICK HERE

Recommended Paging Equipment Broker

Pat Merkel

Telephone: 770-638-1006 left arrow CLICK TO MAIL

I have known Pat for many years. We worked together at BBL Industries in Atlanta about 20 years ago. She is a friend—you can trust her. If you are hunting for some paging infrastructure equipment, Pat can help you find it.

PDR photoFLEX™ Telemetry device

A reader has 190 surplus Tellus one-way PDR's (paging data receivers), model no. TSPM9FXSB, tuned to 929.0125 MHz, re-tunable 929-932 MHz (synthesized), with RJ-11 out. All are in original bubble wrap/individual cardboard box packaging.

For general info on the product click here. For technical specs click here.

These are a steal at $49 each—(FOB source USA)—if you take the whole batch. If you want to buy them, please contact me by e-mail or telephone at: . They wont last long at this price.

outr net logo


handhelds image

For All Popular Wireless Handhelds

Want to see some ROI? How about Field Force Automation with faster dispatching of technicians and better inventory management using wireless devices? For more information please call me so we can talk, and check out their web site at: www.outr.netleft arrow CLICK

These customized solutions cost a lot less than you might think.

Wireless Automation

Check out the following four categories of two-way wireless data communications. We have the ability to customize solutions to meet your (or your customer's) needs.

Data CommunicationsLevel 1A basic ReFLEX transceiver, sending and receiving serial RS-232 ASCII data.
Telemetry (Alarm and Control)Level 2An enhanced ReFLEX transceiver, monitoring alarms from a remote site, and sending commands to the remote site.
Asset or Fleet TrackingLevel 3An enhanced ReFLEX transceiver, with the addition of a GPS module for the reporting of accurate locations to enable tracking.
Field Force AutomationLevel 4An enhanced ReFLEX transceiver, with the addition of a GPS module and a handheld computer terminal for full automation of field service activities all the way from the customer's location back to the service company's back office.
AMTEL Wireless can generally turn a specification into a prototype in two to four weeks. If you have an interesting application in mind, please give me a call so we can talk.


brad photo

With best regards,

brad's signature

Brad Dye

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Web:Consulting and Job search page left arrow CLICK HERE
Can I help you with some consulting on one of your projects?
I am also looking for a full-time position and I am willing to relocate.
FLEX, ReFLEX, and InFLEXion, are trademarks or registered trademarks of Motorola, Inc.
CreataLink is a trademark of SmartSynch Communications Corp. The product and trademark were formerly owned by Motorola Inc.
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