Sigtronics Intercoms. Sigtronics pioneered the voice activated intercom market in 1974 and continues to deliver value and performance today in the FAA TSO approved SPA-400 and SPA-600 intercom series. Radio priority avoids stepping on incoming and outgoing radio messages. Choose either rectangular (horizontal or vertical) or circular faceplate mounting configuration to fit anywhere in the cockpit. Pilot fail safe feature allows pilot to always hear radios.
Sigtronics SPA-400 Four Place Panel Mount Intercom	Sigtronics SPA-600 Six Place Panel Mount Intercom
Reversible face plate included for vertical or horizontal mounting Size - Panel 2.5" x 1", Chassis 4" x 2.5" x 1" Weight - 4.5 oz chassis, 5.5 oz jacks & wiring harness Installation hardware included, including jack kit & pre-wired harness Features: The SPA-400N and SPA-600N have circuitry that allows you to use them either in the voice activated intercom mode or in a push-to-intercom mode. In order to use it in the push-to-intercom mode, you will need to install a separate PTT switch for this purpose. This feature is sometimes desirable in open cockpit and ultra-light aircraft where wind noise can be a problem. Using a large windscreen on the mic is very helpful, however. Special High Noise circuitry Stereo capability: If you want to have stereo/switching in the aircraft, order our ST-400N and our S-45S or S58/68S headsets. High Noise Environment Intercom Series SPA-400N & SPA-600N The High Noise Environment Intercom Series is designed specifically for experimental, ultralights, warbirds, helicopters and other high noise aircraft. Push-to-intercom allows switch activation as well as voice activation when desired. Tested by Sigtronics at ambient noise levels of between 115-120 decibels, the SPA-400N and SPA-600N outperformed all other intercoms on the market, panel mounted as well as portable.