Aviation banner image Sigtronics Logo banner image


Microphones and Intercoms for High Noise Environments

Communication in a very high noise environment such as an amateur built aircraft or warbird requires a good intercom system. You must have, in addition to an intercom engineered for a high noise environment, a properly designed headset and microphone. The three parts – intercom, headset, microphone – working together will provide you with the best communication performance for the most demanding of aircraft.
All Sigtronics intercoms are available in high noise environment models.


M-80H Microphone

M-80H Microphone
Sigtronics has over 45 years experience working in very high noise environments such as the North American T-28. The M-80 and M-80H microphones have been developed specifically for use in high noise aircraft like the T-28. This microphone has a narrow bandwidth and the proper gain for use in this extremely demanding environment. The narrow bandwidth of our microphones is designed to carry voice frequencies, rejecting all others. The gain of our microphones are optimized for voice sound levels to maximize the signal to noise ratio, and thereby the intelligibility.
Product Page


SPA-400N Intercom
The SPA-400N intercom has been designed to work in the very high noise environment and has been extensively tested in the North American T-28. This intercom has internal circuitry that is specially tailored for very high noise. The intercom also has a push to intercom feature that is very useful for open cockpit aircraft or helicopters where an observer may lean out and place his head in the downwash of the rotor. To use this feature, the squelch control is turned full counter clockwise which disables the squelch. By depressing a push to intercom switch the squelch is then opened allowing intercom communication. Once the squelch is reset, the voice activated squelch will operate normally.
Product Page

SPA-400 Intercom

Heavy Duty Windscreen

Heavy Duty Windscreen
When using a headset in an open cockpit aircraft, care must be taken to shield the microphone from direct air flow from around the windscreen. Wind has an enormous amount of energy that will trigger an intercom squelch or even saturate a microphone. One way to minimize the effects of wind is the use of a heavy duty windscreen such as Sigtronics P/N 100593. In situations where the wind is too strong or where the turning of the head places the microphone directly in the slip stream, the push to intercom feature of the SPA-400N can solve this problem.
Product Page


Portable Intercoms
The SPO Series of portable intercoms are available in high noise versions. The SPO-22N is a two place portable version of the SPA-400N intercom. It has the special circuitry that is tailored for very high noise, however the SPO Series does not have the push to intercom feature. Portable push to talk (PTT) switches are used to transmit to ATC. Other portables in the SPO high noise Series are the four place SPO-42N and six place SPO-62N intercoms.
Product Page

The Transcom III Stereo intercom high noise environment models are the SPO-23N, SPO-43N, and SPO-63N.
Product Page

SPO Series of portable intercom

At Sigtronics we fly in and understand the high noise environment that you operate in. Our high noise products are designed, engineered and manufactured to produce the best possible results in these extreme conditions.