Thomas Morzinck. DO 0 OT
VHF COM MU
NICA
TIONS
2189
Oscilloscope Line-An alyz
The unit to be de,crlbed
and dl' play 01 any I lnvle Une on a I tandard
o
lcillo
scope
.The
eecre..
ha"
lng
Ihe
ena
ble
clrcullIIdel lg
I landard oulpu
l lhe,elec
nedlor
lle"
el.
"
Ideo
1.
INTRODUCTION
The IaSl 10 years
prOC8MlO'iJ
e"eel
add,hONII onlormahon SIgnals. which are nol
,nlended
creasing
Broadcasl
TEXT and o
Illms add
VISIONS (2) technique The SIS technique
(Sound"n·Sync) has been decided upon lor the
IransmlSSlon 01hlgh·hdelily sound. also dala and
marker SIgnals canbeencountered
All these nono(llsplayed SIgnal. are
blanking and
IIgnal
normal oscdloBCOptfs Irace For thiS laetllty. a
SynchroniZing Irame
. lhe 8lTlefglng meo.a has len ,Is
upon
tor
leIev1S1On
l'Onal.
and cannot r&!lably be evalualed on a
120
on
the de\oelopmelll of
the VIdeo SIgnal The
"'SlbIe display . II everymore In·
th.r
.ynchrOfllllng
oIlers liS VIeWers VIDEO-
Similar servICes and VHS rent-
accord"'9
musl
IranSlTUS5IOl'I
10 the MACRO-
cemee
portiOflS01lhe vcec
be prepared whICh IS
In the
able 10
tion
grammablemanner from an
2.
PRINCIPLE
A synchrOf'llztng pulse
to
pnrnes
dala
Cll'CUIII5
COU"I. the honzonlal
of
preselecled poonlln
lemal
enables the presentation
01lines tooccur alwaysal the same polnt In lime
leg
The number 01displayed lines ISseleeled on lhe
OSCilloscope by Ihe hor,zonlal
The displayed time duration lor only one line
(64 ,",s) IS100 short lor Iha Ilace 10 have the requned b
co"
ma.,
A"
'''.
Should &everal II
lime
er
Accessory
be
tflggered In a cenn.te and pro-
edernal
source
CIfC\III
. wtIlch has
!he
desifed
Y1deo
Iflpul
SIgnal
(level
the
~
".
and Irame
Star1ed
kom
Ingger Input 01 an OSCIlloscope This
aller the 10th
"lliance
lroi ot thl! OSCilloscope mUSI be Increased 10
mum andior the amblenl hghhng reduced
Oscilloscope
.
Ihe
II".}
and therefore the brilliance
hood
""
Irace bnIkance tnereases propor.
pulses
the hall
kame
pulses
lime
and produces , al a
. an Impulse torthee.·
01.
Slnglellneor
speed
would alsobea"
be
displayed at lhe same
been
pes
neg ).
A counllng
PIcture which
sertel
control
adva,,-
VHF CO MMUNIC ATlON S
2189
tlonally USing a proprietary small service oscilloscope. a Single. complete line can be made
VISible:
clearly
are
dlSll11Cl
prinCipleISshown clearty in fig. 1
groups of about 10 to 15
even with a small screen size, The
uoee
3.
THE CIRCUIT
There have already been several Ci
lished (3) . (4). whiChmay also be claSSifiedInto
voec.
synchrOOlZlng
There are venous poSSible solutions The TBA
920, used here. and the TTL series
v.eee-
srqnCI
or digital
comcos
rCUits
.
les
pub-
are not
I'
stare-ot-rne-arr component s bul they are unproblematical In their
probably already In
wailing lor something useful to do (fig. 2)
Highly Integr8ted solutions may be more elegant
but do not allow the same soft ot control over all
lhe
Individual parameters. For SIgnal sources
do not possess the normal synchroniZing
whiCh
pulses (satellite teleVIsion), an
COflsl
,tulion would be indispensable,
3.1. Vi
deoAmplll
The
veee
ampillier musl match the Inpul Signal
the
follOWing
to
video Signals.egfrom a Video recorder (1 Vcr!
75 II FBAS pos,), can be processed directly by
Oscillo
~\~
I
,
sync.- pulse cucurte Standard
scopr
I,
'11'_
..'
employmenl and are
the amateur's
ier
Junk·bo~
e~tern81
re-
rAl
~
C>
C-
'11.......
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OOOO
T
0"
LA=:
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000 600l(1 -(J' 00 90lBt ·B41
Z@d@n
vor..chIIL,n,
Yo"
'I I
0 ...•
(oun
lfr
I I I
LA=:
prnt
! IB(OI
1r
! !
."
,
(
.,
.
~
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F
ill
. 1:
Prlnc lp•• 01e vl!M'o
liM enelYler
121
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rlf'-
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8m
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11
VHF COMMUNICATlON S
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A920
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Fig. 2:
el
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'r
VHF COMMUNtCAn ONS2189
a lelevlSIOn LSI-Ie (e g TDA 3701 (4' or TDA
IS))
2595
Ttle TBA 920 has been
pos
ilive sync ,
1 V and a prlll-amplll,er ISttlere!ore neces-
least
ThiSwas taken Irom (6),
sary
When other veecSignals are to be displayed a
sUitable
several
would be the most coovemenlllOlutlOh
3.2.
Sync.$eparatlon
The
comPOS
SIgnal complete
sumed 10belamlliar to the reader,
The TV-IC TBA 92018used In a standard
and connected
to ground }, The capacitor at ptn 14 (10 nF MKH)
must havlll a very cIose talerance as
Quency-oetermfnlng pal101the
beller to construct It lrom several smaller parallel
capacitors to achieve
point is not cteervee. the hOrlzontel
have a very limIted capture ,ange,or indeecl,
Will
none at all! The halH rame Impulses a
passll/ely
dIsadvantage
when para$lllC pulses le g
occur In the SIgnal.
generatlOt"l
ately aMer the halt-frame Impulse
suppress these SIgnals. the
taken via an Invel10r 8ta98 to the h' st mono-
pulsn
amplifier must be provided Maybe
Inputs with sw,tchable Signal proce
Ition 01 a typica l lelevl
In the IIIdeo-record mode lpln 16
by means 01 an RC-network The
of thIS ' Imple CUCUlt
01
spurIOU
designed
trom an Inpul SIgnal 01 at
with sync, pulses Will be as·
the eeact value II tt ne
Thll
causes the 1
S v
er1alpulses Immedl'
10 work with
ssll'!Q
SlOl'l
pctu
CirCU
nie
In
eue
crc
urt It may be
OSCilla
ree
_lfacted
15
manlIest
MACROVISIONI
""Qu
In order to
Vel1
lCal s'Onal IS
tor
la'
stable Inthe 74
wave pulse whose WIdth
eccot
Irom a
ne
edge
b1
ThiS
scaler and It suppresses every second
frame Impulse Only by these means can the
lollowlng
over lhe lUll number 01IIfl8Sl625)
In order to achieve a
hne sync. pulse, tngger
the
not reset by the hall-Irame pulse but by a
IS
re
horizontal sync pulse The relevant SIgnal
sequence
Following the
lI
hall·trame pulse
Irame pulse
output
-
and whICh
(2 _74lSOO),
At this lime, the
horizontal
uwenor
counter.
This manner 01recovem'lQ the Impulse has the
lallowlng
US
aj By
line toIlowlng the selected lineWI"bedisplayed
on the screen
b) SInce no account has been taken In the sup-
preUlOfl
lS22
1whIChgenerales a
eQUa
ls lhe duratIOn01
100 (unc" tall Itnes1118
genuine hall·lrame pulse and ,ts leading
ethe ne_1
-stableIIconnecled as a dlvide-by-two
pulse
as.
two
ing Ihe horizontal pulse.s• rese!.
b1
-stable (74L573)
counterbepre-adjusled 10 operate
hed
relationship between
IIg
nal. the counle,
ISshown Inflg . 3
auppreSBlOl'l
by MF 1 andevery
by the "Ip-llop. MF 2 produce s an
oIlhe
samewidth as a line length
ISused as a gate lor the AND gales
amvtng pulse Irom the TBA 920
OSCIllator appears at Ihe output 01the
poSItive re58t
dIsadvantages -
of every second hall-Irame pulse In
01
PUI58
for the lallowing
SQua
re-
tnggered only
eeu-
any
spurIOU
second
nail·
the
S
.
'"
<,nc
00 OCT
123
Fig
,
<II
:
TN
prOvlllOnal
phologrloph
llr
.
lhow
1....:1
tor 1
llln
..
1purpo
VHF COMMUNICA TIONS 2189
__
r,.,
ln
Itln-plill"1.....,Nt_II.11
...
.
bu
lili
naca...T
....
un"
II only
whiCh halt of
when"
'1
."
the
trame
IOhubeen
II II . II can0CC\Il' 1tIa
Miec1ee1
."
323
,,,""',..,
For amateur
are largely wreleYanl A system ahC displa
error of .. 1 II very eaSIly acoomodaleel by the
,-
The Quest
Qu.taQU
5 - lirst ha
3.3. The Cou
Tha
adjustable counter BCD
outputs can be used lor the SWitCheS or SImple
S1epSWltC
lhe selecteel number has
pulse
to tnggar the
'"
purpolMtS
oOn
ICklyby observing the successive
lHrame
nt.
processed sync . pulses are taken 10 a pre-
hel
appea'
i at
0I01loscope
.both
IheMdiuav
01 the hall·lrame can
. 4 • second hall·lrame
r
types Wllh
With a suitable
the
last 74
ecee
been
reached, an1m·
lS
85 whICh
bese"l
matn.
antagn
pulsel
ne;altv
When
II
used
y«!
eeI
1.
4.
II
CONSTRUCTION
""hough
been
as a basl
has therelore not
.
lor
The constructIOn
one cecwt et a lime and operallonally testing II.
Particular cere Shouldbetaken With the adjust·
ment
e
It is also posSIble 10 work With video sourca.
haVing 525
measurement
canbebuilt With , wllchable InpulS to vanou.
pre-amptll..,.
reset
a ameli
number
ccoemet
the counter would be that at OK 1OF 002 (7).
01the TBA
eo. IhlsCIrCUIt
il
or design , A reproducible PCB Iayoul
been
IhOuld
920
IIMlI
acceleory lor
npu
poIar
ts
of worlung UnitShave
.as
only Intended
provided A SUitablePCB
be e"ectlKl by
,
a'
60 Hertz, A vary versatile
l'''
the
' and e.terna! clock and
eQUIPPIng
OSCilloscope
VHF COMMUNICATlONS 2189
5.
REFERENCES
(1) Aohde UlnCh:
WDA·Compulerclub
mc6l86,S
(2) SUlrawsky. Hans-Werner,
MACAOVISION (A)-VHS·KoplerschuIZ
TV·AmaTeur 70/88. S,21
Nacnwesen
(31 Lemke . Arno '
H·lmpuls·Vorwahlzahlel
FUNKSCHAU 11176. S 459 f.
661,
mncvanv
,t
rrnt werteren
AMATEUR
Interested
AMATEUR
HOME
In
....
TV-OX
CONSTRUCTION
(4) Larell. Sleglnfld:
Zeilen·Pmzen e
FUNKS
CHAU9
l84, S 80 It
(5) Vgl. Da1enblal1TOA 2595: eeseIS word
bevorzug
verwendel
(6) Wawor, Kan·Helnz
G1elchgescha ltat
FUNKSCHAU 1
(7) Kestler. Joachim :
FM rranscewer with Mullochannel
Syn1heslzer
Part I : 80 Channal SynTheSizer 'or 25 kHz
Spacing
VHF COMMUNICATIONS
P.130
11UI
KOpielschulZa us1as1el
21B4
. S 79 !I
-14
5
TV
TV-DIGITAL
-VISUAL
PICTURES
EFFECTS
vecs
.1973 00, 3.
VIDEO -
•••.
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ormati
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ITISH
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SATELLITES.
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ie
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Eur
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opean
ogn
ieed
qan i s e
det
ail
ewoodRoad,Hi qh
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suba
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ierec
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e
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ite
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erly
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125
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