Tesla BM 510, Instruction Manual

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tomto druhu provozu ćas. łupu, umoźiiujici roz-
vinuti prubghu s 3x vyssi rychlosti. Obraz do
synchronniho stavu nastavime potenciometrera
„Citlivost“ (R119).
IV.
z p
O
s o b y m
E
r e n
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PRlKLADY OBSLUHY V PROVOZU S CASOVOU
ZAKLADNOU
Mereni stfidave slożky napeti
Mgfime-li stfidavou slozku napgti, nastavime
funkćni pfepinag S201 do polohy S203 do
polohy „0“. V teto poloze je stridavd sloźka
pozorovaneho prubghu zobrazena na stinitku.
Je-li frekvence mgfenś stfidavg slożky pozoro­
vaneho prubghu pfilis nizkś, provddime mgreni
v poloze pfepinace „
“z duvodu omezeni
chyb. PfisluSnou velikost stfidave slożky na­
pgti Ss dostaneme takto:
Na rastru pomoci dilkoveho dgleni odecteme
velikost od kladneho po zśporny vrchol pru­
bghu v dilclch. Takto ziskan^ rozmgr nśsobime
udajem, ktery je dśn polohou knofliku „V/dil“
zesilovace, pfićemż potenciometr jemne regu-
lace zeslleni musi byt v poloze „Kai. Y“.
Ndsobime jestg dglicim ćinitelem sondy, po-
uźitś pro ziskśni mgfenśho napgti. Vyslednd
velikost napgti tedy je : dglici pomgr sondy
x V/dil x vyśka obrdzku = napgti Ss. Pro n&-
zornost pfedpokl&dejme pouźiti sondy BP 4631
s dglicim pomgrem 1 :10, knoflik „V/dil“ v po­
loze 2 V, v^ska ohrśzku na stinitku dle rastru
je 4 dilky.
10 . 2 . 4 = 80 Vss
Mgrime-li sinusove prubghy, ziskane napgti
pi’evedeme z napgti Spieka—Spieka na efek-
tivni nebo stredni hodnotu obvykl?m zpuso-
bem.
Mereni okamźite hodnoty napeti
Mgfici metoda k mgreni okamźite hodnoty na­
pgti je v podstatg shodna s metodou popsanou
v mgreni stfidave slożky napgti. Pfepinac
vstupu zesilovaie S201 pfepneme do polohy
„ “. Mgfime-li okamżitou hodnotu napgti
ve vztahu k ngjakemu potenciślu (obvykle
k zemnimu), musime si pfedem nastavit pfi-
sluSnou uroveii referencniho napgti, odpovi-
dajici velikosti na stinitku. Je-li napf. provś-
dgno mgfeni na + 100 V potenciślu, referen in i
uroveft zemg. Jinś uroveil muże byt pouźita
zeni teto urovng popiSeme pro nejbgźngjśi
uroveft zemg. Jin& uroveii mfiże byt pouźita
obdobng.
amplifier can be turned to the position “X CAL.“
to start the time magnifier, which triples the
sweep rate. The image can be synchronized
by means of the “TRIG. SENSITIVITY“ poten­
tiometer (R119).
IV . M E T H O D S OF M E A S U R E M E N T
EXAMPLES OF TIME-BASE OPERATION
Measurement of the Alternating Component of
a Voltage
If the alternating component of a voltage is to
be measured, set the input switch S201 to the
position
and the input switch S203 to the
position “0 “. The alternating component of the
course being observed is now displayed on the
screen. If the frequency of the alternating
component being measured is too low, perform
the measurement with the switch in the po­
sition “ r t o
reduce the errors. The corres­
ponding peak-to-peak voltage of the alternat­
ing component is evaluated as follows:
Read off the distance between the positive and
the negative peak in terms of the graticule
divisions. Multiply the magnitude so obtained
by the value indicated by the position of the
“V/DIV“ knob of the amplifier, the fine gain-
adjustment potentiometer being in the position
“Y CAL.“.
Now multiply the product obtained by the fa c ­
tor of the probe used to detect the voltage
being measured. The resulting voltage is thus:
probe fa ctorxV / D IV xim ag e height = p-p vol­
tage.
To illustrate the calculation, let us assume the
use of the BP 4631 probe with a division ratio
of 1 : 10, the “V/DIV“ knob to be in the posi­
tion 2 V, and the screen image height in terms
of the graticule divisions to be 4 divisions:
1 0 X 2 X 4 = 80 Vp.p
if sine-wave effects are being measured, the
usual methods are used to convert the peak-
-to-peak value to the R. M. S. or mean value.
Instantaneous Voltage Measurement
In its principle, the instantaneous voltage me­
asuring method is identical with that descri­
bed above. Change the amplifier input switch
S201 to the position
“^zrz“.
If the instantan­
eous voltage value is to be measured with r e ­
ference to a given potential (usually the earth
potential), it is essential first to preset the
appropriate reference voltage level correspond­
ing to the size of the image. If, for inst., the
measurement proceeds at + 100 V potential,
the reference level will also correspond to
- j -
100 V. The provision of this reference level
will be described for the most frequently used
earth potential. Any other level can be attai­
ned by analogy.
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