Becker europa TR, Руководство по обслуживанию

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Balance according to the variometer change or core variometer change
Screw a) variometer carriage to the left-hand stop. Signal generator set to 510 kHz.
This corresponds likewise the 510 kHz mark on the scale of the recipient.
Oscillator Trimmer C 238 Syndicate planning on NF-largest Ausgangsspan-.
b) bring variometers slide clockwise,
ie unscrew completely. Signal generator set on 1630 kHz. This also corresponds
to 1630 kHz on the dial of the receiver.
MW oscillator series inductor L 215 Syndicate output voltage on NF-largest
education.
c) operation a) and b) if necessary repeat until the waste same points correspond to
the prescribed adjustment frequencies.
provide d) dial pointer of the receiver and the signal generator 560 kHz. By means of
the antenna trimmer (C 2) and the intermediate circuit trimmer (C 221) Adjust on
NF-largest output voltage.
e) dial pointer of the receiver and the signal generator on 1630 kHz ask.
If now, by rotating one of the two trimmers (C 2 and C 221) voltage, a further
increase in the NF-source be detectable, so it is recommended according to the
instructions given in point
"Gleichlaufkontrol le" further
method.
Synchronization control
Vote receiver and signal generator on common frequency of 1630 kHz. By means of
the antenna 2 so-trimmer C as the intermediate circuit trimmer C 221 synchronism
control by adjustment thereof to make NF largest output voltage.
B eCaution feature:
Have the trimmers are screwed, so the variation of the forward or the DC is too large,
consequently the vertical speed core question must be turned out (of threaded nipple).
Do the trimmer, however, be turned to achieve the greatest audio output voltage, the
vari- tion is the forward or the DC is too small, the associated vertical speed core would
be screwed.
The operations are to be repeated until no Nachab- equals longer necessary.
Control usually characteristic
The control characteristic of the device is ated CONTROL l, if necessary at the
following frequencies:
LW = 270 kHz MW = 1000
kHz KW = 5,975 MHz
The modulation depth of the RF signal is in this case 30%. coordinate of about 50
microvolts, receiver and transmitter measuring precisely to one another with a small
RF signal.
The Meßsenderspannung wi rd increased to 50 mV and the audio output voltage
across the speakers - set equivalent resistance by means of the volume control to 2.45
V (+ 10 dB absolute). When reducing the signal voltage of 50 mV to 50 microvolts the
LF output voltage (in MW) may drop by more than 10 dB. This corresponds to a
low-frequency voltage of 0,775 V (zero dB absolute).
If the available workplace RF voltage less
exceed 50 mV, it is sufficient if necessary for measuring a signal voltage of 10-30 mV,
as a result of the Regelfunk- tion at Meßsenderspannungen between 10 and 50 mV,
the LF output voltage varies only slightly. (<1 dB, or less than 10%)
Measured values ​​for the control range:
MW ~ 63 dB (approximately 1: 1400) LW ~
55 dB (1: 562) KW ~ 60 dB (approximately
1: 1000)
sensitivity values
MW at 1 volt LF output to 5 Ω measured: MW at 1 volt LF output to 5 Ω measured:
560 kHz = 3uV 1000 kHz =
4.5 uV 1630 kHz = 6 uV
LW at 1 volt Output NF-measured at 5 Ω:
145 kHz = 12 uV 270 kHz =
14 kHz = 400 uV 16
microvolts
KW at 1 volt LF output to 5 Ω measured:
5.975 MHz = 4.5 uV
6.175 MHz = 4.0 microvolts
FM (FM) at 0.7 value of the limiter:
88 MHz = 3.5 microvolts 97
MHz = 3.5 MHz = 108
microvolts 3.5 microvolts
Scale levels in the LF part
NF (0.1 uF) fed via C 301 on the basis of 301 T at 1000 Hz sinus. The audio input NF (0.1 uF) fed via C 301 on the basis of 301 T at 1000 Hz sinus. The audio input
signal is approximately 5.5 mV at 2 V AF output voltage at 5 Ω measured. Following
signal is approximately 5.5 mV at 2 V AF output voltage at 5 Ω measured. Following
level values ​​refer to 2 V NF output voltage to 5 Ω load resistor was measured. In a con
trol le by means of an oscillograph no curve distortions may thereby become
trol le by means of an oscillograph no curve distortions may thereby become
noticeable.
Base T 301 = 5.5 mV base T 302 =
4.8 mV base T 303 = 63 mV
EUROPA TR / LMKU 24 V
The 24 V version EUROPE TR LMKU different from the 12.6 V version only in the LF
part. The RF / IF section
is for
6 / 12V and 24V identical. To ensure that all descriptions and test and calibration
instructions are the 12.6 V receiver share for the 24 V version. The 24 V NF-part differs
in Nichtumschaltbar- the operating voltage, using ness other final-stage transistors, a
different output transformer and eini- gen resistance values ​​(see diagram 156902-01)
from the 6/12 V LF part.
A) Setting of the collector current (without LF signal) A) Setting of the collector current (without LF signal)
1. ammeter between the negative and center tap (black line) of the output
transformer turn.
3. The collector current wi rd with the adjustment potentiometer R 318 set to 60
mA.
B) Examination of the collector current as a function of B) Examination of the collector current as a function of
Fluctuation of the battery voltage.
In high rules of U sheet to 30 V, the collector current must remain
below 70 mA.
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