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SPA-4S Two or Four Place Stereo Intercoms

  • FAA TSO approved.
  • Pilot fail safe feature allows pilot to always hear radios.
  • Use Satellite Radio, MP3 or CD players as audio source.
  • Reversible face plate included for vertical or horizontal mounting.
  • Radio priority assures that ATC hears only the crew member transmitting.
  • Installation hardware included, including jack kit and pre-wired harness.
  • WARRANTY: Five years parts and labor.
SPA-400 Intercom

Compact Stereo System
The SPA-4S is a 2 or 4 place voice activated intercom with inputs for stereo music. It is a compact system that allows it to fit in space critical panels. The SPA-4S uses the industry standard Sigtronics squelch, fast on slow off for hands free communication. The music will full mute during ATC communication and partial mute during intercom communication. When radio / intercom use is ended the music will gradually return to its previous volume.

Easy Upgrade
Each intercom comes complete with all necessary mounting hardware, jacks, and two 4-foot pre-wired harnesses. The SPA-4S only requires 1" X 2.5" of panel space, mounts horizontal or vertically, is 4" deep, and weights 5.5 oz. The SPA-4S intercom can easily upgrade the SPA-400. The SPA-4S uses the same panel hole pattern and interface cable as the SPA-400. A second cable is provided for the music inputs and headphone outputs.

High Noise Environment N Series
The FAA TSO approved SPA-4SN is available for the high noise amateur built aircraft and helicopters. As with all of Sigtronics' products, the SPA-4S / SPA-4SN are RFI and EMI immune. The SPA-4S intercom is constructed of high quality components and carries a five-year parts and labor warranty. The SPA-4S will operate on an input power of 11 VDC through 32 VDC. Maximum current drain 0.10 Amps.



Features SPA-4S SPA-4SN
Headset Positions: 4 4
High Noise: No Yes
Size: 4" x 2.5" x 1" 4" x 2.5" x 1"
Weight Unit: 5.5 oz. 5.5 oz.
Weight Jacks/Harness: 7.0 oz. 7.0 oz.
Warranty: 5 Years 5 Years
Price: $306.00 $330.00


SPA Faceplate

Adapts all SPA Intercoms to standard 2.25 inch round instrument hole.
Part Number: 900068
Price: $10.60

Sigtronics SPA Intercom faceplate


SPA-4S / SPA-4SN PDF Instructions
Installation Instructions
Model: SPA-4S and SPA-4SN
Panel Mount 4 Place Stereo Intercom. Standard and High Noise Versions.
Operating Instructions
Model: SPA-4S and SPA-4SN
Panel Mount 4 Place Stereo Intercom. Standard and High Noise Versions.
Installation Instructions
Model: SPA-4S and SPA-4SN (Out of Production)
Serial Numbers: 4603444 and lower
Panel Mount 4 Place Stereo Intercom. Standard and High Noise Versions.
Operating Instructions
Model: SPA-4S and SPA-4SN (Out of Production)
Serial Numbers: 4603444 and lower
Panel Mount 4 Place Stereo Intercom. Standard and High Noise Versions.
Helpful Hints
Model: SPA-4SN
Helpful Hints for Communicating in Unusually High Noise Environments.
SPA Panel Template
Models: SCI, SDB, SPA, and Sport 200
Panel Templates for intercoms.
Radio Keyline Modification
Model: SPA, SDB, SCI and Sport Intercoms
For KMA-20 Audio Panels and ICOM A220 Radios.

Figure 4 installation drawing modification for specified audio panels, radios, and jacks.
AUX Audio SPA-4S: Auxiliary Audio Input
AUX Audio SPA-4SN: Auxiliary Audio Input
Headset Jacks: U-174/U
Radio: Garmin GNC250/XL
Radios: ICOM A3, A6, A22, and A24
Radios: ICOM A-200 and A-210
Radio: King KY 97A
Radio: Microair 760
Radios: TERRA TMA 330D, TMA 340D, and TMA 350D
Radio: Apollo SL-40