Quantcast 85-HZ DIVERSITY OPERATION

 

Click here to make tpub.com your Home Page

Page Title: 85-HZ DIVERSITY OPERATION
Back | Up | Next

Click here for thousands of PDF manuals

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Logistics
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
   
   

 

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Back
85-HZ OPERATION
Up
TM-11-5805-387-34-2 Modem Radion Teletypewriter MD-522A/RC (NSN
Next
Section IX. METERING STAGE ANALYSIS AND SWITCHING
TM 11-5805-387-34-2
1-70. 85-HZ DIVERSITY OPERATION
When MODE SELECTOR switch S4 is set at 85 HZ DIVERSITY, + 22 volts, +20 volts, and ground are applied to
the appropriate circuits as follows:
The +22 volts from the preregulator is not switched to any special circuitry in the 85-Hz diversity mode.
The +20 volts from the regulator is applied through contacts 6 and 4 of MODE SELECTOR switch S4F to pin 15 of
transmitter module connector XA3, A3J1, energizing divide-by-10 circuit A3A1Q11-Q18 for nsk operation.
Ground is applied through S4A, S4C, and S4F as follows:
Switch S4A grounds receiver module pin XA4, A4J1-6 through contacts 4 and 6, connecting tty squelch adjust
A4A2R1 to ground through A4A2R31 in all nsk modes. This action compensates for the difference in noise
content between fsk signals and nsk signals caused by the wider fsk bandwidth.
Switch S4C grounds the output of 600-ohm voice amplifier A3A2Q8 through contacts 12 and 10, and the
modem 50-ohm mike output through contacts 4 and 6. This action prevents the modem from introducing noise
into the voice input of the associated radio transmitter.
Switch S4G grounds transmitter module pins XA3, A3J1-5 and 8 through contacts 4, 6 and 10, 12, respectively.
When pin 5 is grounded, the output of mixer amplifier A3A2Q2 is applied to the 425-Hz nsk section of FL1
through diode switch A3A2CR3. When pin XA3, A3J1-8 Is grounded, A3A2C1 parallels A3A2C2, narrowing the
pass band of sine wave pass filter A3A2C1, C2, L1 for nsk tones.
1-71. 85-HZ + VOICE OPERATION
When MODE SELECTOR switch S4 is set at 85 HZ + VOICE, + 22 volts, +20 volts, and ground are applied to the
appropriate circuits as follows:
The +22 volts from the preregulator is applied through contacts 12 and 11 of MODE SELECTOR switch S4F to pin
17 of receiver module connector XA4, A4J1.  The +22 volts forward biases channel 1 switch A4A2Q3, effectively
grounding the input to receiver module tty channel 1.
The +20 volts from the regulator are applied through contacts 6 and 5 of MODE SELECTOR switch S4F to pin 15
of transmitter module connector XA3, A3J1, energizing divide-by-10 circuit A3A1Q11-Q18 for nsk operation.
Ground is applied through S4A, S4B, and S4G as follows:
Switch S4A grounds receiver module pin XA4, A4J1-6, through contacts 5 and 6, connecting tty squelch adjust
A4A2R1 to ground through A4A2R31. This action compensates for the difference in noise content between fsk
signals and nsk signals caused by the wider fsk bandwidth.
1-58

Privacy Statement - Press Release - Copyright Information. - Contact Us

Integrated Publishing, Inc.