User Guide

NHB–3
Technical Documentation
PAMS
Tuning Instructions
Original 26/97
12
– Adjust the level of signal CHF to minimum by varying D/A converter value
with cursor left and right keys or <+> and <–> keys.
– When value is OK move to the next option with cursor keys.
– Select option ”TX I and Q DC offset” .
– Adjust the level of signal CHF to minimum by varying D/A converter value
with cursor keys or <+> and <–> keys.
– When value is OK move to the next option with cursor keys.
– Select option ”Tune Amplitude Difference”.
– Adjust the level of signal CHF+67.7 kHz to minimum by varying D/A convert-
er value with cursor keys or <+> and <–> keys.
– The amplitude difference between CHF+67.7 kHz and CHF–67 kHz should
be >35 dB (See picture).
– When value is OK move to the next option with cursor keys.
– Select option ”Tune Phase Difference”.
– Adjust the level of signal CHF+67.7 kHz to minimum by varying D/A convert-
er value with cursor left and right keys or <+> and <–> keys.
– When spectre is minimized press <Esc> key and store new values to EE-
PROM with <Y> key.
– Press <ESC> key to return to upper menu (Testing and Adjustment).
– Select option ”RF Controls”.
– Change ”TX Data Type” value from one to zero or from zero to one depend-
ing on wich value the option had.
– Press <ESC> key to return to upper menu (Testing and Adjustment).
– Select option ”Adjustment”.
– Select option ”TX I/Q Tuning”.
– Press <Y> key to load values from EEPROM.
– Minimize the spectre like explained earlier. Check the other side of the
spectre once more.
– When both sides of the spectre are minimized, press <Esc> key and store
new values to EEPROM with <Y> key.