Sigtronics SPCC-3 - Manual (Page 7)

FIGURE 3
SPCC
Pin #
FM RADIO
1
2
4
3
5
Mic Audio Input
Ground
Headphone Audio
Output
Transmit Key Input
FIGURE 5
SPCC
Pin #
FM RADIO
1
2
3
4
5
Headphone Audio
Output
Ground
Transmit Key Input
FIGURE 4
SPCC
Pin #
FM RADIO
1
2
4
3
5 33K *
1K *
Mic Audio Input
Ground
Headphone Audio
Output
Transmit Key Input
* Use 1/8 or 1/4 watt resistors
FIGURE 2
Male five pin connector shown from solder side:
PLUG END SOLDER END
1
2
3
4 5
1
2
3
4 5
FM Radio Interface Cable Wiring Examples
The following are some examples of possible wir-
ing schemes for the FM-1 and FM-2 interface cables.
Only the FM radio functions are shown for the
FM radio end of the interface cable, because the
connector(s) used by radio manufacturers varies
widely. You will have to consult the radio manual
or manufacturer for the connector(s) used and pin
assignments for your particular FM radios. Also,
Sigtronics has extensive radio interface experience
and can assist in any question you might have con-
cerning this or any other aspect of the SPCC. Of
course, Sigtronics can build the FM interface cables
for you to your specifications, if desired.
Figure 3 shows the most common of such cables
with its “high level mic input” and standard “ground
to key” interface. This cable will work with most
standard police, fire, and business band radios as
well as aircraft type radios.
Figure 4 is similar to Figure 3 but is used for radios
requiring a low level mic input such as marine type
radios.
Figure 5 shows typical cable wiring for radios that
sense the presence of mic current to transmit. Most
ICOM hand-held radios are set-up this way.
FM RADIO INTERFACE CABLE WIRING
FM Radio Interface Cable Connector Pin Assign-
ments for both FM-1 and FM-2 Connectors
Pin Function
1 Mic audio output to FM radio
3 Receive audio input from FM radio
4 FM radio ground
2,5
Transmit key output to FM radio (Normally
open relay contacts closed during FM ra-
dio transmit)
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