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Mik.e Slone WB0OCO
PO Box H
Lo wden IA 52255
Interfacing Packet Radio
toATV
The BRATS ATV Group in Iowa
was the first known group to mteqrate
packet radio and SSTV
modes into a Fast Scan TV Repeater
. The idea and appticauon
is unique and not all that complicated.
Ten folk s of the ao-rnerreer
group went packet and six got into
SSTV becau se of this feature.
Packet
The Commodore 64 is the computer
for this system. It uses a
direct color composite video feed
output that goes to a channel Inpul
to the ATV/A transmitter. The
AEA PK-64 is the syste m INC. It
provi des la rge 40 -column text
lettering, which is easier to read
on ATV. The system also doubles
as a vital, wide-coverage. 24hou
r pac ket station digipealer
(WB0BIZ-1) on 145.01 MHz, all
housed at the Davenport, Iowa ,
KWQC-TV (NBC) Studio. BRATS
plans to expand this system with a
Kantronics KPC-4 Dual-Port system
to connect VHF to HF.
Since the data-controller TNC
system is multi-mode, the ATV
Club can choose to monitor packet,
Morse. Rny, ASCII or AM­
TOR. They place the system on
CW occasionally to let listeners
practice Morse code over two melers
(144.340 MHz FM) and watch
the characters display back on
UHF-ATV.
The unique aspect of interlacing
a packet radio system to a
FSTVIR is the ability to see what
th e TNC dig ipeater hears and
sees. Monitoring such a system
via ATV lets the group keep in
touch with the operating status 01
the TNC. A quick look on ATV,
verifies the system's condition.
Slow-Scan TV " Repeater"
The BRATS Group had on loan
at one lime a ROBOT 12OOC CoIor
SSTV Convener interfaced 10
their N9CAf ATV/R system .
BRATS hopes to permanently install
such a unit to add the excttemen
t of a color display and autom
at ic !rame ra te d i spla y. A
black-and-white, 16-shade gray
level. 8.5 sec/piCture, ROBOT 400
SSTV converter is now interfaced
58 73 Amateur Radio. April, 1988
Numbe, 19 on your Fell'dback eard
Ham Tefevision
Dayton Draws Near!
The 1988 USArvs.soec-ccm
Journal ATV Workshop sessions
are shaping up with some great
guest speakers. This group will
meet again this year at the Ramada
Inn North (1-70 & 1-75) in
Suite 212. Ride one of the shutne
buses over from the Hamvention
on Friday or Saturday to anend.
The room will open at 5 PM Friday
night with the programs beginning
at 7 PM . B ill Brown
WB8ElK from the Findlay, Ohio,
ATV Group is one of the slated
guest speakers. He will discuss
his group successful launching
and operation of last summer's
helium- filled balloon carrying two
meters and UHF ATV. John Beanland
G3BVU of Spectrum International
will talk about how to use
bandpass filters to get rid 01CRM.
Saturday's session opens at 3
PM, and the evening programs
begin promptly at7 PM. Two reps
from the BATC ATV Club in England
will speak on the state of
Ham TV in Europe. Tom O'Hara
W60RG has another good line up
lor ATV forum meeting this afternoon.
This columnist will give a
short presentation on how to bedeck
with bells and whistles an
ATV repeater syst e m . The
smallish suite
room hold s
30-40 silting
people, and
has standing
room for a few
more.
I'll be at the
in-r oo m bar
keeping all refreshed,
a s
la st year.
There is a $11
sessio n door
ad mission to
help pay for
the $100 1
night ro om .
Come early to
get a good
co m f y seat
and
please­
into the ATV system. A few years
ago, these converters sold for
$795 . ATVers can find these converter
s now at hamfests for
around $1001 The units present a
good resolut ion picture that displays
very well on FSTV.
Audio from VHF (144.340 MHz
FM) feeds into the ROBOT 400
with the composite video monitor
leed jack tapped to provide the TV
output. The unit is lett in the AC
power ON position with a system
switcher activated upon touch ­
tone user call-up. Members send
taped or real-time SSTV signals
over VHF and watch them repeated
(cross-band and crcss-mcoej
Of' ATV! Some system users pipe
in SSTV sig nals a ll of the HF
bands, such as those from the
Saturda y afterno on W1JKFI
W9NTP net
at 1 4 . 2 3 0
MHz . All 01
UHF AT Vdom
can enjoy
the show
without i nvesting
o ne
d ime i n
SSTV!
One time
a few years
ag o , o u r
g r 0 u p
placed the
on-line
ROBOT
1200C into
aut oma tic
picture-camera
sn atch
mode at 72
s econ ds .
One 01 u s
fed p ro - Bob W7KPW of the Central Texas
c e s s e d ATVGroup.He'satthe14SO'levelof
vid eo into a remotely-located W7KPW A TVIR
the camera Repeater system pointed to ward
input jack Austin, Texas.
from the ATV/R receiver output.
Stations on UHF would put their
best pictures on at 439.25 MHz,
hold for a minute or SO 10 auowthe
120 0C to c aptu re the locked
frame , then unkey on UHF and
look at what they sent!
leave your
cancer sticks
in the car .
Talk-in at
Dayto n lor
ATVers is on
147.450 MHz simpte :w: FM (the
AT V sound c han nel inp ut) or
144.340 MHz FM. With luck, there
Will be a working station in the
room monitoring the Dayton ATVI
R system.
Don Miller W9NTP will hold his
annual SSTV get-together at the
Holiday Inn North, not far from the
Ramada. Fred Sharp W8ASF of
Timekit will team up with John at
the Spectrum International booth
in the main arena. The weather
facsimile folks will meet on Sunday
morning.
VCR Library
Alter nearly a year-long absence,
the " A5 Videotape Ubrary"
is back in full swing to
USATYS members! A new catalog
list is out and available to
USATVS Members lor o nly a
SASE. Tapes include FCC lectures,
ATV demos. namtest shows
and forums, NASA space films,
ARRL re leases, overseas T V
video exchange s , FSTV DX
tapes, " R"-rated TV bloopers,
and cl ub system presentations.
USATVS Members may borrow or
obta in duplicate copies 01 established
programs for a slight lee.
New Book Reprints
Ralph Wilson WB0ESF of ESF
Copy Service s 4011 Caearview
Lane, Cedar Falls, Iowa 50613
has a few new " A5/Spec-Com
Reprint Booklets" on the market.
Booklet '100 are co pies of the
" sold out" Everthing You Always
Wanted 10 Know About A TV But
were Afraid 10 Ask manual. Booklet
110 1 is a new release full of
information about building ATV
repeaters. Booklet #108 is on
packet radio. He has several other
booklets, al11 00 pages or more in
content on RnY, satellites and
TYRO, lacsimile, SSTV, computers.
UHF antennas. and construction
projects. The booklets are
well worth the mol"l8y at $10 each .
Include an extra dollar lor return
postage. Also look for them on
sale at Dayton at the ATV Workshop
sessions.
Frequency QRM Letter
Finally, a word about the Irequency
coordination problem violalions
against AT Vers. The
USATVS dratted up a 3-page letter
with several addenda inlormanon
sheets, c harts. and tables
about ATV Interference. This letter
went to nearly all ARRL-recognuec
Freq uency Coordinators,
some ARRL and FCC Officials,
and key USATVS committee
members . Copies are available
lor a double-stamped SASE. This
type of thing should have been
done years ago, to avoid a lOt of
unnece ssary misunderstanding
and problems.
Hopefully, a better understanding
and alertness 01 ATV groups
around the country will at least
temper th e ig no ra nt and pre ­
judiced manner in which some
FCs are acting. Register those
ATV/R system sl Reier area FCs to
this Iener on any future problems
or CRM correspondence . 735 de
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