The TLM 170 R was the first microphone with the now so successful fet-100 technology. It offers balanced transformerless signal pick-up and maximum dynamic range with extremely low self-noise. Five polar patterns can be selected with a rotary switch. In the sixth switch position, "R", the polar patterns can be switched remotely using the N 248 power supply without the need for a special cable.The microphone also has a switchable 10 dB pre-attenuation for very high sound levels and a subsonic filter with an operating frequency of 100 Hz.Applications:The TLM 170 R condenser microphone is a switchable large-diaphragm microphone that is distinguished by its transmission characteristics and various switching options. It is used in a wide variety of applications in radio, film and television, as well as in the semi-professional sector.The directional characteristics can be switched both directly on the microphone and by remote control from a power supply unit provided for this purpose.Acoustical properties:The double diaphragm capsule located in the wire mesh basket of the microphone has particularly flat frequency responses for all adjustable directional characteristics. This is true not only for sound arriving from the front, as is often the case, but also for sound arriving laterally within an angular range of more than 100.This is why the diffuse-field frequency responses up to 10 kHz run parallel to the 0-curves. In practice, this applies to the sound components that reach the microphone indirectly via reflections in the recording room, so that the sound character of any reverberation that may also be picked up is not changed by the microphone. Since no resonance effects are used to achieve the above-mentioned microphone characteristics, the microphone's impulse behaviour is excellent. It is therefore able to transmit all equalising processes in music and speech without distortion. The capsule is elastically mounted to protect against structure-borne sound transmission.Polar patterns:In addition to the omnidirectional, cardioid and figure-of-eight polar patterns, hypercardioid and wide cardioid polar patterns are also available. The hypercardioid allows - better than the cardioid - to suppress sound sources positioned to the right and left of the object to be recorded, while the wide cardioid is advantageous for transmitting extended sound sources.Remote control:The remote control of the directional characteristics with the aid of the N 248 power supply unit is done by varying the phantom voltage in the range 48 V3 V (the corresponding standard allows a range of 4 V). In the switch position "R" (= remote: remote control), the TLM 170 R microphone evaluates the absolute level of the phantom voltage and sets itself to the corresponding polar pattern. As with conventional operation, the normal 3-pole microphone cable is used; cable lengths of up to about 300 m are permissible.Electrical features:The letters TLM stand for "transformerless microphone". The output transformer normally used in the TLM 170 R has been replaced by an electronic circuit which - like a transformer - provides good unbalance attenuation. Therefore, interference signals affecting the balanced modulation line are suppressed as usual. Please note that this item is offered as B-stock and may therefore have slight optical defects. The original packaging may be damaged or missing. B-goods are checked by us for full functionality and sold as technically flawless. Of course, there are no di