Midland SYN-TECH 70-050 - Page 16

ALIGNMENT INSTRUCTIONS
70-050/055
Remove the 8 screws securing the top and bottom covers. Loosen the 4
screws securing the PA assembly and pivot t.he top of the PA assembly
to the rear. Turn the volume control to a mid position and the squelch
control fully clockwise, if the 70-E10 test set is used, the _R_y) 5 pin
test socket should be connected to CM101 for transmitter alignment and
the WHITE 5 pin test socket to CM201 for receiver alignment. Both test
sockets should be connected with the unused socket position toward the
rear of the radio. Refer to the 70-E10 TEST PINS switch position
underlined in the steps below. Supply power to the radio and connect a
wattmeter and dummy load with a reduced power output for a frequency
counter and modulaton meter.
X-
7f
X-
X-
X-
IMPORTANT NOTE * * * * * * * * * *
A "95" error code display and triple beep can be expected at
unit turn on if the channel frequencies programmed in the
E/PROM are outside the band for which the Main VCO is curen-
tly aligned. To eliminate this error indication, adjust L702
(TX board) for 4 volts at TP701. The normal alignment proce¬
dures can then be performed.
Error codes "90" through "94" indicate the E/PR0M module to
be missing, improperly inserted or incorrectly programmed.
Refer to the general troubleshooting chart if these error
conditions occur.
* -jc- * ■ *
"JC- '/c ■ X- 'X- X- X- X* :(• ~X* -X* X-
VCO AND TRANSMITTER ALIGNMENT
l.Turn RV502 (PA) maximum counterclockwise.
MAIN VCO ALIGNMENT
2. T h e Main VCO should be adjusted with the radio operating on the
channel and in the condition (transmit or receive) corresponding
to the highest programmed frequency. If the highest frequency is
a transmit frequency, select this channel, key the transmitter
and adjust L702 to give 4.0 VDC at TP701. If the highest program¬
med frequency is a receive frequency, adjust L702 for 4.5VDC at
TP701 while in the receive mode.
TRANSMIT VCO ALIGNMENT
3. M o n i t o r TP101 (TX) with a DC voltmeter. Key the transmitter and
adjust L107 for 4.5 VDC.
TRANSMIT DRIVER ALIGNMENT
4. M o n i t o r CM101 Pin 2 ( p o s i t i o n 9 ) with a selected channel frequen¬
cy near the center of the programmed frequencies. Adjust. CV102
for a dip betweeen two peaks.
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