Kenwood MC-60A - User Manual

COMMUNICATIONS
MICROPHONE
VMCcC-GOA
INSTRUCTION MANUAL
@ FEATURES
The MC-60A microphone is designed expressly for use with
your amateur communication system. It provides excellent
performance when used with any KENWOOD transceiver,
thereby upgrading your existing system.
The zinc die-cast base offers high stability, and is complete
with a feather-touch PTT switch, rocker UP/DOWN switch,
an impedance selector switch and a built-in preamplifier.
NOTE: For UP/DOWN switch operation, refer to your
transceiver’s manual.
CAUTION:
1. The microphone is constructed of precision parts. Do not
open the microphone, as it may result in serious damage.
2. The microphone is sensitive to shock and vibration.
Treat it gently.
@ INSTALLATION
1. Battery Installation (Fig. 2)
1. Remove four screws as shown.
2. Install two alkaline AA celis (not NiCd). Observe
polarity.
3. Reassemble base unit.
NOTE: 1. Radios with power available at the mic con-
nector (for autopatch microphones) will not
require batteries.
2. The preamp on/off switch is located on the
underside of the base unit. The preamp is on
in the forward switch position.
2. Connection to your transceiver.
1. Slide the microphone into the plastic bracket.
2. Connect the short base mounted cable to the rear of
the microphone.
3. Connect the retractile cord from the base to the
transceiver.
4. The microphone may also be used separate from the
base unit, by connecting the retractile cord directly
to the mic. However, the preamp is located in the
base unit. Preamped operation is not possible with a
direct transceiver hookup.
5. The MC-60A is supplied with a standard PG-4C 8 pin
to 8 pin retractile cord. For radios with a four pin mic
connector, use a PG-4A (4 pin to 8 pin) option cord.
For radios with a six pin mic connector, use a PG-4B
(6 pin to 8 pin) option cord.
ON/OFF STBY Switch
Impedance Selector
UP/DOWN Switch
Connect to
Radio Mic
Terminal
Mic.,Preamp ed
(Underside)
LOCK Switch
@ OPERATION
The MC-60A is equipped with a PTT switch for easy transmit/
receive changeover. The PTT switch can be locked, if desired
by pressing the Lock key. To unlock the switch, simply
press the Lock key once again. The Mic on/off, Lock, and
PTT switches are all in parallel.
e Connection
To operate the microphone without using the stand, con-
nect the retractile cord directly to the microphone, and
use the slide-switch on the microphone for transmit/
receive changeover.
e Impedance selection
The microphone impedance is selectable between 5002
and 50k by using the slide-switch on the microphone
regardless of whether the stand is used. Most Trio-
Kenwood HF products are 50k2. Some will operate from
500—50k2. All VHF and UHF mobile radios are 5002
impedance.
Install Batteries
“BA" Alkaline
(Not Ni-Cd)
Fig. 2 Battery installation

Summary

Microphone Features

Microphone Installation

Battery Installation

Details on installing two AA alkaline batteries, observing polarity, and reassembling the base unit.

Connection to Transceiver

Instructions for connecting the microphone to the transceiver using the plastic bracket and cables.

Microphone Operation

Using Without Stand

How to connect the retractile cord directly to the microphone for use without the stand.

Impedance Selection

Details on selecting microphone impedance between 500Ω and 50kΩ using the slide-switch.

Additional Functions and Specifications

UP;DOWN Switch Function

Description of the UP/DOWN switch on the base used for selecting transceiver frequency.

Microphone Preamp Operation

Information on the microphone preamp, its control switch, and battery usage for VOX operation.

Technical Specifications

Detailed technical specifications including type, impedance, sensitivity, and frequency response.

Overview

1. Function Description
2. Important Technical Specifications
3. Usage Features
4. Maintenance Features

The KENWOOD MC-60A is a communication microphone designed for amateur radio systems, offering enhanced performance for various Kenwood transceivers. It features a robust zinc die-cast base, providing stability during operation.

Function Description

The MC-60A serves as a primary input device for amateur radio transceivers, converting spoken audio into electrical signals for transmission. It incorporates a Push-To-Talk (PTT) switch for easy transmit/receive changeover, a rocker UP/DOWN switch for frequency selection (refer to the transceiver's manual for specific operation), and an impedance selector switch. A built-in preamplifier enhances audio output, making it suitable for a range of radio equipment.

The microphone can be used either with its stand or as a handheld unit. When used without the stand, the retractile cord connects directly to the microphone, and a slide-switch on the microphone itself handles transmit/receive changeover. However, the preamplifier function is only available when the microphone is connected to its base unit, as the preamp circuitry is housed within the base.

Important Technical Specifications

Type: Communication type dynamic microphone with PTT circuit. Element: Moving coil type, unidirectional. Impedance: Dual impedance, selectable via a slide switch.

• 50 kΩ ± 30% (at 1000 Hz)
• 500 Ω ± 30% (at 1000 Hz) Most Trio-Kenwood HF products are 50 kΩ, while some operate from 500-50 kΩ. All VHF and UHF mobile radios typically use 500 Ω impedance.

Sensitivity (0 dB = 1V/μ BAR, 1000 Hz):

• Microphone:
  • -54.5 dB ± 3dB/50 kΩ
  • -71.0 dB ± 3dB/500Ω
• Preamp out:
  • -56.0 dB ± 3dB/50 kΩ
  • -71.0 dB ± 3dB/500Ω
• Preamp in:
  • -50.5 dB ± 3dB/50 kΩ
  • -59.0 dB ± 3dB/500Ω

Frequency Response (-6 dB):

• Microphone, or Preamp off: 150 Hz – 10 kHz
• Preamp in: 200 Hz – 7 kHz

Recommended Operating Distance to Mic: 10 cm (4") minimum.

Usage Features

PTT Switch: The PTT switch allows for quick switching between transmit and receive modes. It can be locked in the transmit position by pressing the "Lock" key, and unlocked by pressing the "Lock" key again. The Mic on/off, Lock, and PTT switches operate in parallel.

UP/DOWN Switch: Located on the base, this rocker switch is used to select the transceiver's operating frequency. Its specific functionality depends on the connected transceiver.

Impedance Selection: A slide-switch on the microphone allows users to select between 50 kΩ and 500 Ω impedance, accommodating various Kenwood radio models. This selection is independent of whether the microphone is used with or without its stand.

Microphone Preamplifier: The MC-60A includes a built-in preamplifier, particularly useful for FM and SSB mobile radios. The preamp is controlled by a switch located on the underside of the base unit. Sliding the switch forward activates the preamp, while sliding it to the rear bypasses the preamp and disconnects the batteries. When the preamp switch is "on," power is continuously supplied, making it suitable for VOX-operated equipment. To conserve battery power, it is recommended to turn the preamp off when not in use, as the amplifiers draw approximately 1 mA.

Connectivity: The microphone is supplied with a standard PG-4C 8-pin to 8-pin retractile cord. For transceivers with different connector types, optional cords are available:

• PG-4A: For 4-pin mic connectors (4-pin to 8-pin).
• PG-4B: For 6-pin mic connectors (6-pin to 8-pin).

The connection process involves sliding the microphone into its plastic bracket on the base, connecting the short base-mounted cable to the rear of the microphone, and then connecting the retractile cord from the base to the transceiver.

Maintenance Features

Battery Installation: The MC-60A requires two alkaline AA cells (not NiCd) for its preamplifier.

1. Remove four screws from the base unit.
2. Install the AA cells, observing correct polarity.
3. Reassemble the base unit. Note that radios providing power at the mic connector (e.g., for autopatch microphones) do not require batteries for the preamp. The preamp on/off switch, located on the underside of the base unit, must be in the forward position for the preamp to be active.

Caution:

• The microphone is constructed of precision parts. Do not attempt to open the microphone, as this may cause serious damage.
• The microphone is sensitive to shock and vibration; handle it gently to prevent damage.

Kenwood MC-60A Specifications