Vehicle Microphones

Electrect gooseneck microphones for – GM-4 vehicles

This category contains variously modified electrect gooseneck microphones of the GM-4 type with the cardioid feature that are imported by our company directly fromChina. There is a FET transistor built in the microphones that amplifies their acoustic signal which is the reason why they require power supply in the range of 1.5 V to 9 V (plus on the live conductor of the shielded conductor). If such power supply is not used the signal from the microphone is significantly weaker and very distorted. The microphones are suitable for public transportation vehicles (we have been supplying them to public transportation companies since 1996).

Basic features of the GM-4 MICROPHONE
Impedance	1 kΩ ± 30%
Frequency range	100 Hz – 16 kHz
Sensitivity	-68 dB ± 3 dB at 1kHz (0 dB = 1V / μbar)
Microphone power supply	+1,5 V up to +9 V at the central conductor
Length of the microphone with an XLR connector	623 mm (initial rendering)
Length of the microphone without an XLR connector	525 mm (shortened length)
Weight	200 g ± 10 g (with an XLR connector)

The following picture shows 2 frequency characteristics of the GM-4 microphone, from the front (blue line) and from the rear (violet line). This clearly shows that the rear direction is suppressed by about 10 dB.

The basic mechanical rendition of the microphone is to be seen in the following picture. The microphones are supplied with a 623 mm long XLR connector or they are shortened by the length of the connector, i.e. 525 mm.

The GM-4 electrect gooseneck microphones are also designed for adding sound to vehicles and for communicating via radio stations where our products are used:

• public transportation on-board computers – EPIS 4.0x,
• regional public transportation on-board computers – type EPIS 5FCx ,
• vehicle digital annunciator units EPIS 2.45.

Order code	Type of the electrect vehicle microphone	PRICE
241.GM-4	GM-4 – Electrect gooseneck microphone with an XLR fork	28 €
7217.GM4U3W	GM-4U3W – Electrect gooseneck microphone with 3 WAGO clamps	39 €
7217.GM4U5W	GM-4U5W – Electrect gooseneck microphone with 5 WAGO clamps	40 €
7217.GM4UD	GM-4UD – Electrect gooseneck microphone with  loose 7 cm conductors	37 €
7217.GM4UK	GM-4UK – Electrect gooseneck microphone with a 5.5 m cable	45 €

Additional remarks to the price and availability:

1. The above stated prices do not include the VAT and are applicable at the purchase of one piece
2. Quantity discount is applicable from 10 pieces in one order
3. GM-4 microphones are in store, other GM-4x types are ready to be picked up immediately or in 1-2 days.

GM-4 – Electrect gooseneck microphone with an XLR fork

The basic rendition of this electrect microphone includes:

1. Body of the electrect microphone in aluminium casing
2. XLR fork connector
3. Black 480 mm gooseneck
4. Soft foam cap

GM-4U3W Electrect gooseneck microphone with 3 WAGO clamps

GM-4 modified electrect microphone set contains:

1. Modified GM-4 electrect gooseneck microphone and a holder with PG 9 (shortened and ridded of the connector).
2. Two-vein cable shielded for the lead of the microphone (the ground of the EPIS microphone is connected with the shielding of the microphone, the shielding of the joining table is not connected).
3. Girder of 3 WAGO clamps and cables placed on the microphone holder.
4. Soft foam cap

GM-4U5W – Electrect gooseneck microphone with 5 WAGO clamps

GM-4 modified electrect microphone set contains:

1. GM-4 electrect microphone with modifications and a holder with PG 9 (shortened and ridded of the connector).
2. Two-vein cable shielded for the lead of the microphone (the ground of the EPIS microphone is connected with the shielding of the microphone, the shielding of the joining table is not connected.
3. Girder of 5 WAGO clamps and cables placed on the microphone holder..
4. Soft foam cap

GM-4UD – Electrect gooseneck microphone with loose 7 cm conductors

GM-4 modified electrect microphone set contains:

1. GM-4 electrect microphone with modifications and a holder with PG 9 (shortened and ridded of the connector).
2. Two-vein cable shielded for the lead of the microphone (the ground of the EPIS microphone is connected with the shielding of the microphone, the shielding of the joining table is not connected.
3. Soft foam cap

GM-4UK – Electrect gooseneck microphone with a 5.5 m feeding cable

GM-4 modified electrect microphone set contains:

1. GM-4 electrect microphone with modifications and a PG 9 wall entrance insulator.
2. 5.5 two-vein cable shielded for the lead of the microphone (the ground of the microphone is connected with the shielding of the cable, shielding of the joining cable is not connected).
3. Soft foam cap

GM-4Ux microphone holder

Pic. no.3: Microphone holder

Pic. no.4: Microphone anchor

Microphones for radio stations

Microphones for TAIT radio stations

These microphones are going to be prepared. They are microphones supplied directly by the radio station manufacturer.

TM 8000 microphone – EP-MIC connector