karn@eagle.UUCP (06/14/83)
A N N O U N C E M E N T
TNC AVAILABILITY
Tucson Amateur Packet Radio Corporation has conducted
extensive testing of a Terminal Node Controller (TNC) design
over the last several months. 172 TAPR TNCs are in the
field, and the "Beta" design has been in continuous testing
since early November, 1982.
In order to more fully discharge our charter in developing
and refining packet radio communications, TAPR is on the
brink of releasing the TAPR TNC to the general Amateur
community. The TNC will be provided as a kit that includes
all parts; comprehensive manual including detailed kit
assembly instructions; custom power transformer with
multitap primary for those in low- or high-voltage areas;
electrically pre-tested printed circuit board with silk
screened parts locations; built-in modem, power supply,
RS232 interface and radio interface.
REFINED DESIGN
For those familiar with the Beta design, the following
improvements have been implemented in the hardware design:
1) 32 k bytes of EPROM (vs Beta's 24 k).
2) 8k bytes of RAM (vs Beta's 6 k).
3) Two 512-bit banks of NOVRAM (vs
Beta's single 256-bits).
4) Modem disconnect, with all applicable
HDLC connections.
5) Improved modem design, with lower
noise floor, greater input signal range,
greater mic audio adjustment range,
improved signal level indicator
circuitry, LED monitoring of additional
signal lines (such as Data Carrier
Detect), configuration of modem
parameters via DIP carrier.
6) Serial I/O port access is via a right
angle pc mount DB25S connector at the
edge of the board.
7) Parallel port access is via a right
angle pc mount DB25P connecter at the
edge of the board.
8) Radio I/O port access is via a right
angle pc mount DB9S connector at the
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edge of the board.
9) Power connection is via an 8-pin
"Molex" style power connector.
10) The +5 volt supply uses 3 amp diodes
instead of the 1N4001s found on the Beta
board.
11) The +5 volt supply has a jumper,
along with additional power supply
connector pins, to support an off-board
5 volt regulator.
12) The power transformer has been
redesigned with 105/115/125 volt ac
primary taps and corrected secondary
windings.
13) The serial I/O port uses pullup
resistors so no jumpers are needed to
support partial RS232 interfaces (such
as "three-wire" terminals).
14) Revised circuitry for calibrating
the 1700 Hz PLL demodulator.
TAPR is currently generating the updated manual and the
board layout is being revised. At the conclusion of board
layout, a trial run of 25 kits will be supplied to a limited
number of Beta sites for testing. This is anticipated in the
late-July to mid-August time frame. We are limiting this
initial release to a few boards per selected existing site
to ensure a rapid turnaround in the testing. It is not our
intent during this initial test to bring more sites up. Once
we have determined that the revised design is working
properly and the documentation is adequate for a reasonably
adept Amateur to properly assemble, calibrate, interface and
place the TNC into operation, the kits will be made
available to all on a more-or-less first-come, first-served
basis.
DISTRIBUTION, SCHEDULING and COST
The mechanism for distribution is simple. The orders will be
handled based on the order in which they are received. TAPR
members will have a degree of priority. Orders for multiple
units will be spaced out somewhat so no one can order a huge
block and tie up distribution.
How do you get on the list? Send your order to:
Tucson Amateur Packet Radio Corporation
PO Box 22888
Tucson AZ 85734-2888
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and include your name, shipping address, etc., along with a
deposit of $25. Upon receipt of your deposit (including 16
days for clearing of non-cashier's checks), you will be
placed in the queue. You will be advised by return mail of
your expected shipping date. Balance of payment is due at
least one week before scheduled ship date (or you may get
bumped!).
TAPR will attempt to have a daytime telephone number where
Visa/MasterCard orders can be placed (with an approximate 3%
adder for such orders).
The price of the complete kit is $240 plus $7 shipping and
handling. This is $29 more than the Beta boards, and the
increase is for the following reasons:
1) There is more memory on the board.
2) We are having the pc boards
electrically tested.
3) There is a 30 days-after-shipment
warranty on the parts (and we have to
make this good, not the chip
manufacturer).
4) We lost thousands of dollars on Beta.
5) We need money to launch our R & D
effort for high-speed UHF linking
systems.
6) We are having a commercial firm do
the kitting for us to conserve our time
for technical work.
Since many of the parts on the TNC are now on allocation, we
have taken the steps to schedule a number of kits. However,
we need IMMEDIATE feedback on your expected needs, as well
as deposits, so we can better plan. Our present schedule
calls for general kit deliveries starting in late
August/early September. We are planning on 25 kits the first
month, followed by 50 kits for each of the following three
months. That is only 175 kits, so if you are interested, act
promptly! If we get sufficient orders, we will modify the
schedule to take care of things as expeditiously as
possible.
PRODUCT SUPPORT
Please note that support of the TNC, including such things
as service bulletins, modifications for improved
performance, announcements of software and hardware updates,
etc., will be done via the Packet Status Register, TAPR's
official newsletter. Thus, it is suggested that purchasers
of the TNC consider becoming members of TAPR.
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Thank you for your interest...
Lyle Johnson, WA7GXD
President - TAPR