Sigtronics SPCC-3 - Manual (Page 6)

2. Set the SPCC aside for a moment. With the FM-1
radio disconnected from the SPCC, transmit as
normal, on the FM-1 radio, to the remote sta-
tion. Transmit long enough so that the receiving
station can get “calibrated” to your transmission
(voice) level.
3. Connect the FM-1 radio to the SPCC as normal
with the FM-1 interface cable. Put on the observ-
er’s headset and turn the SPCC “ON”. Verify FM-1
radio reception. If OK, use observer’s PTT to trans-
mit to your receiving party. If receiving station
reports weak transmission, use the screwdriver to
turn the FM-1 MIKE GAIN ADJ clockwise a small
amount. If they report garbled or broken trans-
missions, turn the FM-1 MIKE GAIN ADJ counter-
clockwise a small amount. Repeat as necessary
until the receiving party reports that transmis-
sions through the SPCC sound as good or better
then when the FM-1 radio is used separate from
the SPCC. That’s all that’s required for FM-1.
4. To set the FM-2 Radio Mic Gain Adjustment first set
the observer’s XMIT SELECT switch to “FM-2”.
5. Take off the headset and set the SPCC aside for a
moment. With the FM-2 radio disconnected from
the SPCC, transmit as normal, on the FM-2 radio,
to the remote station. Transmit long enough so
that the receiving station can get “calibrated” to
your transmission (voice) level.
6. Connect the FM-2 radio to the SPCC as normal
with the FM-2 interface cable. Put back on the
observer’s headset. Verify FM-2 radio reception.
If OK, use observer’s PTT to transmit to your re-
ceiving party. If receiving station reports weak
transmission, use the screwdriver to turn the
FM-2 MIKE GAIN ADJ clockwise a small amount.
If they report garbled or broken transmissions,
turn the FM-2 MIKE GAIN ADJ counterclockwise
a small amount. Repeat as necessary until the re-
ceiving party reports that transmissions through
the SPCC sound as good or better then when the
FM-2 radio is used separate from the SPCC. That’s
all there is to it!
The A/C Radio Mic Gain Adjustment is located to
the left of the FM-1 radio interface connector. Again,
the A/C Mic Gain Adjustment, in most cases, will not
have to be changed from its original factory setting.
If however, your aircraft radio transmissions through
the SPCC are reported as weak or garbled, you will
need to reset this level. The adjustment procedure
is similar to that of the FM mic gain adjustment
above. You can, however, use the “BYPASS” mode
of the SPCC to aid in the adjustment. Arrange to
have someone with an aircraft radio nearby with
whom you can transmit and receive. Then, proceed
as follows:
1. Set the ON/BYPASS switch to the “BYPASS” posi-
tion and connect the unit as normal to power and
aircraft radios. Plug in the pilot’s headset and PTT
switch into the jacks on the left side of the SPCC.
(The FM radios and observer’s headsets and PTT
switches are not needed for this adjustment.) On
the pilot’s side of the SPCC, set the XMIT SELECT
switch to the “A/C” position, and all three receive
select switches to “OFF”.
2. Put on the pilot’s headset. Transmit and receive to
your nearby station, using the pilot’s PTT switch
and headset, as described in the Initial System
Check-Out section on page 8. Verify good trans-
mission and reception. In this mode you are by-
passing the SPCC and verifying the clarity of the
aircraft radios.
3. If radios check out OK, then turn the ON/BYPASS
switch to the “ON” position. Verify aircraft radio
reception. If OK, use the pilot’s PTT to transmit
to your receiving party. If the receiving station
reports weak transmissions, use the screwdriver
to turn the A/C MIKE GAIN ADJ clockwise a small
amount. If they report garbled or broken trans-
missions, turn the A/C MIKE GAIN ADJ counter-
clockwise a small amount. Repeat as necessary
until the receiving party reports that transmis-
sions with the SPCC turned “ON” sound as good
as that when the ON/BYPASS switch is “BYPASS”
mode.
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