T1 PRI D-channel monitor
This device collects ISDN PRI D-channel messages and sends them, via
Ethernet, to an IP address obtained from a DHCP server. It can be powered
from an external supply or from the Ethernet line.
The first board powered up and ran, with fully operational debug capability.
No changes to hardware or programmable logic were required. Less than one
hour of software debug at the first Beta install and one firmware upgrade in
the field resulted in a completely functional unit.
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USB digital/Analog audio FM transmitter
This board converts digial audio, passed from a PC though a USB connection,
to analog. The analog audio appears on line out (RCA) jacks and a headphone
jack. There is also an FM transmitter, which can transmit audio content from
the USB or line input jacks.
Unfortunately, funding was cut just before the first batch of prototypes was
to have been built, so the project was canceled.
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BDM to PC parallel interface
Background debug interfaces are typically top secret and ridiculously
expensive. This one is dirt simple, uses readily-available socketed DIP
parts and costs about $2.00 to build. Toss in a little top-secret software
for a DOS or Windoze PC and debugging occurs directly from the assembly
source listing files. Bugs are fixed before the massive, expensive debugging
system finishes loading.
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PCI quad comm board
This was a hardware port of an existing ISA card to the PCI bus. The goal
was to maintain 100% software and hardware compatibility between the PCI and
ISA versions. I proposed an integrated version that would have been cheaper
and simpler, but the direct port was chosen because nobody wanted to make any
changes to the embedded code.
The layout guy used the wrong library part for the processor and I had to
"adjust" it on the first prototype (see inset image). Otherwise,
this was a boring and uneventful project.
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T1/E1/J1 PRI D-channel monitor
This device allows the ISDN PRI developer to monitor the D-channel messages
sent and received by any T1, E1 or J1 device having monitor jacks. Data may
be monitored in real time, logged to a PC and/or logged to onboard Compact
Flash.
Total development time, from conception to working product, was under 2
months. The first prototype board (shown in the picture) was fully
operational at first power-up, requiring no changes to hardware or
programmable logic.
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ISDN Terminal Adapter
Central-office quality POTS ports, two multi-protocol data ports, with
software selectable RS-232, RS-422 and V-35 modes and bulletproof
highest-reliability hardware design distinguish this product from other
similar units. Firmware includes patented D-channel processing
(US Patent 5,748,628)
, which offers total international switch-independent operation with NO
programming required. A rich feature-set, including analog and digital
caller ID, call-waiting caller ID, SMDR, EKTS, conference calling, multi-way
calling and a streamlined command interface devoid of those cumbersome "AT"
codes, all in 40 Kbytes of code, make this product unique in the industry.
Third party tests have shown consistently higher throughput than competing
units having microprocessor clock speeds as much as 50% higher.
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ISDN U-Interface Drop-and-Insert Test Set
This is a one-of-a-kind product, which allows the ISDN developer to monitor
or log the ISDN U-interface D-channel or either or both B-channels in real
time without compromising the normal operation of the equipment connected to
the ISDN line. With proper PC software, the D or B-channels may be inserted
toward the central office, the user equipment or both, allowing emulation or
simulation of any equipment or events. Two RS-232 links are available for
connection to one or two computers to facilitate any conceivable test
situation.
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Cellular Fixed-Station Adapter
This product was developed to bring telephone service to areas where the cost
of running physical copper wire is prohibitively expensive. It connects
between a normal telephone set and mobile cellular radio, emulating the
handset back toward the radio and emulating a central office toward the
telephone. Low cost was the primary design goal, which was met through the
innovative use an inexpensive 8-bit microcontroller and sophisticated
real-time software to generate all central office tones digitally.
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Network MPEG-II Movie-On-Demand Set-Top Box
This device has allowed its manufacturer to add Digital Movie-on-Demand
to the list of capabilities of its proprietary high-speed daisy-chainable
network. On request from the user, compressed digital movies or other
audio/visual material can be supplied from a central server and viewed
through a normal television receiver any place on the network. When the
set-top box is turned off, normal CATV or antenna programming is
supplied to the TV.
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ISA-bus T1 Card
This was one of the first T1 cards available for the PC. It features
on-board DSU, time-space switch, proprietary interboard connection bus and
MVIP bus interface. This board was in production for well over a decade
and became the nucleus of several PC-based digital-voice products. Of
special interest is the external frame sync port, which allows the board
to be connected and synchronized to a wide variety of digital-voice and
channelized data devices. It can be the timing master or slave to the
external device, using any of three different frame-sync modes
Both the DSU and CSU build options of the board are shown.
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ISA-bus 8-channel Digital Voice Card
This board provides 8 FXS central-office-quality POTS circuits on a single
PC plug-in card. It interfaces to other digital-voice components through a
proprietary interboard connection bus or an MVIP connector.
There was a 4-channel predecessor and the basic design was adapted to create
an FXO version. All cards can be configured for loop or ground start.
The image has been cropped to eliminate the manufacturer's name.
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RS-232 to RS-422 converter
Sure, everybody makes these now. Back when this was created, there were
only a few companies making them and they were terribly expensive. My client
needed a cheaper alternative, so I whipped this out in a couple of hours.
Twenty of these boards could be built for the cost of a single off-the-shelf
equivalent.
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ISA-bus Multi-protocol serial controller
This board acts as an intelligent hub for two 2.048 Mb/sec HDLC RS-485 links
which can be connected to a variety of serial devices.
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Multi-protocol module serial controller
This board is used at the other end of the RS-485 link provided by the ISA bus
multi-protocol serial controller where intelligence is required. The async,
sync and high-speed serial boards shown below can be stacked on this board to
form a complete serial module.
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Octal async serial module
This board plugs on to the multi-protocol module serial controller to form an
8-channel asynchronous serial module.
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Quad sync serial module
This board plugs on to the multi-protocol module serial controller to form a
4-channel synchronous serial module.
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Dual high-speed sync serial module
This board plugs on to the multi-protocol module serial controller to form a
2-channel high-speed synchronous serial module, providing 2 channels of HDLC
or bisync at up to 2.048 Mb/sec.
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T1 serial module
This board is used at the other end of the RS-485 link provided by the ISA bus
multi-protocol serial controller to form a T1 serial module. It can be used
alone to connect to a short line or stacked with the LIU module shown below
for long lines.
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T1 serial module LIU
This board stacks on the T1 serial module, disabling its CSU and providing
an FCC-approved long line connection.
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32-channel async daughter card
This board plugs on to the ISA bus multi-protocol serial controller to
provide another 32 asynchronous RS-232 channels.
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Universal IR remote decoder
This was designed as an IR remote receiver that would send decoded IR codes
to a PC though the serial port. It was used for sales presentations to
simulate the operation of a proposed product on a PC.
I modified the firmware so that it would decode any IR pulse stream and report
it to the PC as an ASCII packet, giving the interval in milliseconds of each
on and off cycle
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Handheld IR remote control
The hardware was simple and basic, taking all of an hour to design. The
firmware took a couple more hours to write, producing in-house development
costs for electronics and software of less than $100. Several quotes from
Asian remote suppliers came in at 100 to 200 times that amount. Mechanical
engineering was another story, but I had no involvement in that.
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Client Side Interactive Video Control System
Using a TV and the telephone line, this device allows compressed video and
audio subscriber information to be interactively presented on the TV.
Navigation is provided by the telephone keypad or an IR remote.
Needless to say, the Internet killed this technology in short order.
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Channel bank dual FXS card
This is a dual FXS voice card for a T1 channel bank.
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Channel bank LIU
These are the LIU cards for a T1 channel bank. The two boards plug together
to form a double-wide module that occupies 2 slots in the backplane.
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Channel bank power supply
This is the power supply card for a T1 channel bank.
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Prototype T1 channel bank
This is really two separate prototype cards screwed together for testing.
The card on the left is the T1 interface and status indicators. The card on
the right is the backplane timing generator and one FXS voice interface.
Several very intelligible phone calls were placed through this crude device.
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OCC phone autodialer
This is an intelligent Other Common Carrier autodialer and call router. It is
programmed with toll-free area codes and prefixes and decides whether outgoing
phone calls should be direct dialed or routed through the OCC. Programming
can be done with the local phone, a local computer via RS-232 or remotely,
using another dialer configured as a DTMF send modem. Once programmed all
blocking table and speed dial data can be uploaded to a computer or cloned
into another dialer.
If you look closely at the date on the EPROM, the firmware was last modified
in May, 2002. The board in the photograph is a spare, but a similar unit
has been in continuous service for the past 23 years.
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Telephone call logging printer
This device prints the time, date and duration of every phone call placed on
the phone line to which it is connected.
Radio Shack expressed an interest in selling a stripped-down version of this
product, but the president of the company that built it refused to negotiate
the price. He wanted to get rich off the one deal with Radio Shack, and when
that deal fell through, his company went bust. Radio Shack eventually had its
own version designed, but it was not nearly as good as this one.
Several Asian companies knocked off the whole design. They even copied the
aberration of the character "Z" in the dot matrix data, which was
inserted purposely for just that purpose (Z was never printed).
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Apple II serial card prototype
Here it is--the first computer electronics thing I ever designed. This never
went into production, but I used this very card right up until the day I threw
my Apple II in the trash.
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