Galaxy DX Radios DX88HL
Documentation Project
CBTricks.com

Transmitter Alignment
See Required test equipment
See Alignment Locations

SETTINGS CONNECTION
ADJUST
 ADJUST FOR
Remove TP7-TP9 Jumper PCB.
TX FREQUENCY:
Set mode to LSB		 Connect Frequency Counter to TP3 (top bare lead of R74).
VR21
 Key TX; Adjust for 16.2675MHz ±20 Hz.
CARRIER OSCILLATOR OFFSETS:
TX Mode
Freq. to 26.965MHz Band E

Connect Frequency Counter to TP6 (top bare lead of R102).

L28

LSB/TX mode: Adjust for 10.6975MHz ±20Hz.

 
Connect Frequency Counter to TP6 (top bare lead of R102).
L27
 USB/TX mode: Adjust for 10.6925MHz ±20 Hz.
Connect Frequency Counter to (top bare lead of R151).
L26
AM/TX mode: Adjust for 10.6950MHz ±20 Hz.

DRIVER BIAS:
Band Switch & Ch. Selector to 26.965 MHz Ch.1 Band E
Mode to USB
MIKE GAIN at minimum.
Remove metering jumper

Connect DC Ammeter between TP9 and TP8.
VR11
 Key TX adjust for 50-75mA.
FINAL BIAS:
Band Switch & Ch. Selector to 26.965 MHz Ch.1 Band E
Mode to USB
MIKE GAIN at minimum.

Connect DC Ammeter between TP9 and TP7.

VR10

VR20

Key TX & adjust VR10 & VR20 for minimum ( 0mA ) current. Next adjust VR10 for 50mA, then adjust VR20 for 100mA total.
Replace TP7-TP9 Jumper PCB.
RF AMP CHAIN:
Replace PCB shorting jumper.
Set mode to AM.
Set RF power switch to HI .		 Connect wattmeter to ANT output.
L43, L44,
L42, L40,
L33
 Key TX & adjust (in order) for maximum RF output . Recheck power at lowest & highest channels; readjust if necessary for balance across entire bandwidth.
SSB CARRIER BALANCE:
Set mode to USB
MIKE GAIN to minimum.		 Connect wattmeter to ANT output.

VR7

 Key TX; adjust for mim. carrier leakthrough on scope or wattmeter. Recheck on LSB mode. If necessary readjust for best balance of sideband suppression between LSB & USB
SSB ALC:
Mode to USB.
MIKE GAIN to maximum.
Inject two-tone audio signal of 500 Hz and 2400 Hz, 30 mV (-18 dBm) at MIC jack.		 Connect wattmeter to ANT output.
audio generator to Mic Jack
VR12
 Key TX; adjust for 25 watts PEP.
AM CARRIER POWER HIGH:
Set mode to AM,
MIKE GAIN at minimum.
RF Power to HI.		 Connect wattmeter to ANT output.

VR13

Key TX; adjust for for 8-10 watts
CAUTION! Do not exceed this level. Damage to power transistors and inability to achieve 100% modulation from insufficient audio power will result.
AM CARRIER POWER LOW:
RF Power to LO .		 Connect wattmeter to ANT output.
VR16
 Key TX & adjust for 1-3 Watt output
RF METER:
Set mode to AM,
MIKE GAIN at minimum. 		Connect wattmeter to ANT output.
VR8
 Adjust so panel meter agrees with Wattmeter.
AMC:
Mode to AM.
MIKE GAIN to maximum.
Inject audio signal of 1KHz 30mV (-18 dBm) at MIC jack.
Connect modulation meter to ANT output.
VR14
 Adjust for 100% modulation depth.
FM DEVIATION:
Mode to FM
MIKE GAIN to maximum.
Inject 1 KHz, 30 mV audio signal at mike jack.		 Connect deviation meter to ANT output.
VR5
 Adjust for total deviation of 4.5 KHz.
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Disclaimer: Although the greatest care has been taken while compiling these documents,

we cannot guarantee that the instructions will work on every radio presented.