Valcom VMT-1 Input Matching Transformer.

Input Matching Transformer

The Input Matching Transformer (IMT) provides two separate transformers: a three-wire transformer to eliminate phantom power and a two-wire transformer with low leakage for compatibility with unbalanced inputs. The IMT also has switchable microphone protection.

Valcom's Input Matching Transformers get the impedance of your speaker and radio system matched so you can run more speakers in less space, using fewer amplifiers.

The benefit of an Input Matching Transformer is that it allows you to connect a telephone set with a low impedance (4-10 ohms) output to a telephone line with a high impedance output. Telephone lines in the USA are high impedance(600-1,600 ohms), which means you need a transformer to connect your phone equipment. The PSTN is grounded at the central office, so your system needs to be grounded also. Valcom's VMT-1 Input Matching Transformer is designed for use with fully amplified commercial systems that have 600 ohm output impedances, and requires grounding at the location

The Input Matching Transformer (IMT) is used to match two audio amplifiers. You would use this device when your amplifier has a higher impedance and is outputting low power, and you want to connect it to another amp with a lower impedance but high power rating.

The Valcom VMT-1 Input Matching Transformer was designed for audio systems that require Video Equipment. Now you can get any VHS video camera, model TV/VCR and bring it up to the highest quality possible. The VMT-1 Input Matching Transformer is engineered to match the impedance of a VHS video camera or television with that of a mic level or line level audio equipment and also provide phantom power.

The VMT-1 Input Matching Transformer is designed to match an audio or video signal source of high impedance (such as magnetic phones and tape recorders) to a circuit that has low impedance (such as telephone lines). The user simply adjusts the matching ratio on the front panel to compensate for the difference in number of ohms between the two circuits. This transformer works over the entire frequency range from 100 Hz up to 20,000 Hz.

The VMT-1 Input Matching Transformer is used for retrofitting an existing wideband input device to use a standard microphone. This unit also engages this system's PTT (push-to-talk) function. The VMT-1 is typically used in courtrooms and intercom systems.