Our Links

Date Link
Feb 28, 2006 Board Layout Software
David - This is the software that Professor Greco used. The free version is limited to 3x4.2 inch boards. Probably not useful for this group.
Feb 19, 2006 Tips on Controlling Clock Skew
Trunk Line System
Sent by Edward.
Edward Kimotho -
Jan 31, 2006 EMS radio nearly ready
Sent by Danielle.
David Glasser - Story about radio intergration in Northhampton County, home to Lafayette.
Jan 31, 2006 12 VDC to 120 VAC inverter
Laura - The link for 12 VDC to 120 VAC inverter. I haven't looked at other manufacturer's websites yet. PPL buys from Nova so that's why I looked htere first.
Jan 30, 2006 Lucid Spec
Ed - I am sure there are many other programs like this out there, but u can have a look at this one to draw up some GUI stuff before actual designing.
Jan 29, 2006 MAXIM home page
Analog Switch main page
4581 data sheet
Danielle - I found this particular analog switch at MAXIM. They had A LOT of analog switches. I picked the 4581 just because it was the first one i saw that was an 8:1 mux. I'm sure there are other parts here or at other companies that would be just as well or better suited for what we need.
Jan 25, 2006 Asterisk
Zach - Open Source PBX System
Jan 24, 2006 Digital Acoustics
Zach - Convert Audio to TCP/IP

From Professor Gum and Professor Jemison

Date Link
April 25, 2006 Ribbon Cables Link 1
Ribbon Cables Link 2
Ribbon Cables Link 3
Ribbon Cables Link 4
Ribbon Cables Link 5
Dr. Gum - Ribbon Cable Stuff
April 25th AN-42028
SCSI Technology
Design Termination
Dr. Gum - Terminations
April 25th Capacitor Data
Dr. Gum - Decoupling Caps
April 14, 2006 Radio failure impairs storm response
Dr. Gum
April 14th The Errors of 9/11 Have City at Work On Radio System
Testimony of Gino P. Menchini Chief Information Officer, City of New York Commissioner, Department of Information Technology and Telecommunications
Dr. Gum
April 10, 2006 Level Shifters
Dr. Gum
April 4, 2006 Digial Audio Sampling Theory
Dr. Gum
Mar 30, 2006 Audio Caps
Dr. Gum - Audio caps
Mar 15, 2006 Solutions for Communications Interoperability
Dr. Jemison - Cisco Solution
Mar 09, 2006 VoIP and Amateur Radio
Introducing EchoLink
Voice over Internet Protocol (VoIP) Accessibility
Equipment Options For VOIP Communication
Get Your VOIP Solution Now
Jeffery W Gum - VOIP
Mar 08, 2006 DC/DC Filtering
Jeffery W Gum - Astron Power Supplies
Mar 08, 2006 Link 1
Link 2
Jeffery W Gum - Phone Signal Level
Mar 08, 2006 More Battery Stuff
Battery Stuff
Jeffery W Gum - Battery Stuff
Mar 07, 2006 Astron Power Supplies
Jeffery W Gum - Astron Power Supplies
Feb 28, 2006 Logic Family Choices
The basics of integrated circuits

Feb 28, 2006 19" Rack Mount Equipment
David Glasser - General Rack information
Feb 27, 2006 Introduction to GAL Devices
Yang Feng Zheng - General specs of different GAL devices.
Feb 21, 2006 Choosing a Charger
Site Battery Backup Systems
Battery Storage Capacity Ratings
AC-DC Power Supplies (100-5000W)
PowerStream Technology

Feb 14, 2006 Xilinx Picoblaze Microcontroller
PicoBlaze for Spartan-3, Virtex-4, Virtex-II, and Virtex-II Pro FPGAs
David Glasser - Microcontroller core for FPGA.
Feb 13, 2006 Telephone line audio interface circuits
Jeffrey W Gum - This has a number of hobby circuits that take 2-wire to 4-wire as we have discussed.
Feb 13, 2006 Analog Telephone Adaptor Reference Design Kit
Hugh King -
Remote Control By Telephone (Specification)
Hugh King -
Feb 7, 2006 VHF/800MHz interoperability
Scott Curry - This article describes how to create a translator (repeater) between two radios. The specific example given is connecting a VHF radio with some simple circuitry to a 800MHz radio so that they can repeat or relay the information on the other radio. It works both ways and is a very simple device. This can be used for directly connecting devices together, it does not help our project too much because it has no way to handle changing talk groups or repeating on more than two radios. There are two links at the end that give examples of similar commercial systems.
Feb 7, 2006 The Definitive Guide to the 16 pin MaxTrac and Radius Option Connector
John Bayard -
Jan 30, 2006 Police, deputies unite via radio
David Glasser - A success story of two agency's talking to each other on different radio systems. No technical details.
Jan 27, 2006 Linux FRS Radio Control
John Bayard - This article explains how we can control a particular low-level radio, including controling the pushbutton, remotely from a Linux program. Includes diagrams, parts needed, and soldering technique. The way talks are going now, with our design plan and such, I don't think this article will help us at all. Thanks, email me if you have any questions!
Jan 27, 2006 Motorcycle Leather, Motorcycle Helmets, Motorcycle Apparel, Motorcycle Gear!! Everything you need on a motorcycle ride!
Laura Fredley - The Air Rider Add-A-Radio Interface allows you to add a hand-held CB radio, GMRS radio, FRS radio, or ham radio to a motorcycle and be fully integrated into your bike's onboard intercom and radio system. This unit is designed to work on motorcycles that already have headset hookups for their AM/FM radios and intercom systems. On the end of the cable is a standard 2.5 mono audio plug. Price: $199.99
Jan 27, 2006 Telephone line audio interface circuits
Scott Curry - This article is basically everything you want to know about land line based telephones. It talks about how the phones themselves work as well as how the data is transmitted over the lines. It also talks about different ways of interfacing the phones onto the networks. I don't think that this article is very helpful to our project because I feel that it is looking at telephone communications at a lower level then we'd ever need to since we are just planning on using the audio input and output adapters on the devices. If we need to tap into land line based phones or need to see how they operate to apply it to another technology, this article would be helpful.
Jan 25, 2006 Vehicle Repeater System
Amanda Driscoll - Existing vehicle repeater systems - handheld radio becomes a wireless remote speaker microphone for the mobile radio in the vehicle.
Jan 25, 2006 What Is a Methodology?
Sherisse Hatcher - The article I read was about methodolgy for designing software. It discuss the approaches that have been taken to designing software from the 1960's to the 1970'and ends with a discussion of object oriented software design. This article will be useful if or when we decide to develop software for the project.
Jan 25, 2006 On the Criteria To Be Used in Decomposing Systems into Modules
Tricia Indoe - This Article was about splitting designs into modules. The benefits of splitting into modules are development time, product flexibility, and comprehensibility. Also, different modules can be designed without the actual knowledge of the design of the other modules and each module can be replaced without replacing the whole system. The article gives two ex&le of how one project can be split up into different modules.
Jan 25, 2006 Prototyping a design?
Edward Kimotho - Prototyping a Design This article discusses the various design methodologies that are used out there. This is a forum where one user discusses the design methodology that he used and the subsequent problems he encountered. Then he discussed another methodology that is a workaround for the problems that he encountered. There were no defined requirements document at the onset i.e. the requirement were not fully fleshed out. Furthermore, the requirements changed over time. As a result, the design that was implemented was inadequate; some of the modules were thrown away and others had to be incorporated. Due to this problem, the designer elected to design with as little detail as possible and would wait until all requirements were finalized before finishing the design with all the details, tests and documentation. Summary The requirements change over time and your designs have to allow for these changes. As Brooks said, "Plan to throw one away. You will do that, anyway".
Jan 23, 2006 ECE 492 - 2004
An ECE 492 website from long ago.
Jan 23, 2006 Interoperability plan now a royal mess
Hugh King - A similar system in Canada did not meet the customer's approval. Reasons were mostly for the lack of coverage but also for busy talk groups, and radios at base stations not being completely powered up.
Jan 23, 2006 A layman's guide to Interoperability
Marc London
Jan 22, 2006 XEM3001 - Xilinx Spartan-3 Experimentation Module
David Glasser - Xilinx Spartan-3 Experimentation Module. Easy link to computer, lots of I/O ports. Comes with driver for the computer and some APIs to make it easy to build a GUI. Seems like a good choice. Costs 200 dollars.
Jan 11, 2006 Technical Evaluation TRP 1000 and ACU 1000
Zachary Silverman - This article is a 51 page document that describes how the ACU-1000 unit works. Below is an expert from the articles executive summary section: The ACU-1000 is designed to allow wireless communication systems to be combined at a common denominator, namely the audio base band. Thus, radios that operates within different parts of the radio spectrum, use different modulation and access techniques, or use analog versus digital encoding can interoperate. This is accomplished by using the received audio from one radio system as the source audio for one or more transmitters of differing technologies. That is, through matrix capabilities the ACU-1000 can apply the audio to a series of radio transmitter inputs. Simultaneously, either one path can be created between two or more radios or several paths can be configured between sets of radios. ----- Executive Summary, ADVANCED GENERATION OF INTEROPERABILITY FOR LAW ENFORCEMENT, 8/25/00 page 1
Jan 11, 2006 Guide Radio Comm Strategy and Products
Yang Feng Zheng - This document mainly focus on the radio communications interoperability, it describes three different strategies and characterize the products that are available to implement these strategies. The strategies described in this document are:
1. Same Radio System: Create one radio system that provides communications for multiple agencies.
1. Swap radios: provides interoperability on a temporary basis. (pg.3)
2. Shared system: a permanent interoperability solution. (pg.4)
3. Commercial services: includes SMR, LLMR and MSS. (pg.5)
2. Common Frequencies: Establish a common frequency and protocol so that transmissions from a subscriber on one radio system can be received by subscribers on a different radio system.
1. Common frequency/channels: program radio belonging to different radio systems to operate on a common channel. (pg.6)
2. Multimode radio: design to provide interoperability by providing capability to operate on multiple frequencies. (pg.6)
3. System to System Gateway: Deploy a gateway device that establishes an interface between radio systems by receiving a transmission from one radio system and rebroadcast it on another radio system.
1. Console patch: patch together two or more radio signals at a communication or dispatch center. (pg.9)
2. Audio baseband switch: extract audio from a radio, then switches the audio to another radio and transmits the audio on a different radio system. (pg.13)
3. Multi-system controller: controlled by sophisticated computer operated network controllers, compatible stand-alone system are linked together to create one large system. (pg.23)

This document also briefly talked about voice over IP, and references to different interoperability products.