Daniels MT-3 Instrukcja obsługi - Strona 9
Przeglądaj online lub pobierz pdf Instrukcja obsługi dla Wzmacniacz Daniels MT-3. Daniels MT-3 20 stron. 132-174 mhz 406-470 mhz low current front end
Drukuj stronęG ENE R A L
Alignment for the MT-3 Front End consists of
tuning the five section preselector filter only.
No tuning is required for frequency changes
within the 3 dB bandwidth of its originally tuned
frequency (5 MHz for VHF and 7 MHz for UHF);
although, without tuning at the 3 dB band edges,
the receivers sensitivity will be degraded. For
frequency changes outside of the Front End's 3
dB bandwidth, use the tuning procedure outlined
below.
R EPA I R NO TE
The MT-3 Front End employs a high percentage
of surface mount components which should
not be removed or replaced using an ordinary
soldering iron. Removal and replacement of
surface mount components should be performed
only with specifically designed surface mount
rework and repair stations complete with Electro
Static Dissipative (ESD) protection.
When removing Surface Mount Solder Jumpers,
it is recommended to use solder wick braid in
place of vacuum type desoldering tools. This will
help prevent damage to the circuit boards.
Printed Copy Not Controlled
R E C O M M E N D E D T E S T
E Q U I P M E N T
Alignment of the MT-3 Front End requires the
following test equipment or its equivalent:
Power supply - Regulated +9.5 Vdc
Spectrum Analyzer with Tracking Generator
Alignment Tool - Johanson 8764
C H E C K P O I N T S
Vsupply:
Preselector Filter Insertion
Loss:
RF Amplifier Gain:
Image Rejection Filter Loss:
Mixer Conversion Loss:
Test Point #1 (TP1):
Test Point #2 (TP2):
Local Oscillator Frequency:
MT-3 Low Current Front End Instruction Manual
5
FRONT END
ALIGNMENT
+9.5 Vdc @ 8 mA
typically VHF: 3 dB;
UHF: 4.5 dB
typically VHF: 20 dB;
UHF: 16 dB
1.5 dB maximum
7.5 dB maximum
+7.4 Vdc
+8.0 Vdc
RF Frequency ± 21.4
MHz
IM11-FE3