Yamaha F-20 User Manual

Thank you for purchasing a Yamaha F-20 Guitar Amplifier.
To get the best results and longest life out of your F-20, we recommend that you
carefully read this manual, and keep it in a safe place for future reference.
● To avoid possible damage do not expose the unit to:
• direct sunlight
• very high or low temperature/humidity
• sand or excessive dust
* Especially inside a vehicle, the temperature may rise
excessively — do not leave the F-20 in your parked car on a
sunny day!
● Before connecting/disconnecting cables or turning the unit on/off, be
sure to set the VOLUME/MASTER VOL. control on the F-20 to 0.
● Keep the F-20 away from neon signs or fluorescent lighting to prevent
noise pickup.
Precautions
Rated Output Power : 20 W
Speaker : 20 cm x 1
Controls : VOLUME, GAIN, MASTER VOL., TREBLE, MIDDLE, BASS,
CH SELECT switch (A/B)
Input/Output Terminals : INPUT, AUX IN, PHONES
Control Panel
Specifications
q INPUT : Connect your guitar to this jack.
w CH SELECT A/B (Channel Select Switch A/B) : Depress
the switch (>) to select Channel B which, can be used to create
distortion. When the switch is in its raised position (?), Channel A is
selected producing a clean, distortion free tone.
A Channel
e VOLUME : This knob controls the volume level of Channel A. This
knob functions only when Channel A is selected (?) with the CH
SELECT switch (the Channel A LED will light).
B Channel
r GAIN : This knob is used to control the amount of distortion. Rotate
the knob to the right to increase distortion. This knob functions only
when Channel B is selected (>) with the CH SELECT switch (the
Channel B LED will light).
t MASTER VOL. : This knob is used to control the volume level of
Channel B. This knob functions only when Channel B is selected (>)
with the CH SELECT switch (the Channel B LED will light).
● Handle the unit carefully — never apply excessive force to the
controls and avoid dropping the unit.
● For safety, always remove the power plug from the AC wall outlet if
there is any danger of lightning striking in your area.
● To prevent damage and possibly electrical shock, never open the
case and tamper with the internal circuitry.
● Never use solvents such as benzene or thinner to clean the F-20.
Wipe clean with a soft, dry cloth.
Tone Controls
y TREBLE : This knob controls the level of the amplifier’s high fre-
quencies.
u MIDDLE : This knob controls the level of the amplifier’s mid fre-
quencies.
i BASS : This knob controls the level of the amplifier’s low frequen-
cies.
o AUX IN : Connect the output of an external audio device such as a
CD, MD, cassette deck, etc, to this jack to listen to audio playback of
the device, along with your guitar, through the F-20 amplifier.
* Use the volume control on the audio device to control its volume level.
!0 PHONES : Connect a pair of headphones to this jack.
* The speaker will produce no sound when a pair of headphones is con-
nected to this jack.
!1 POWER : This is the amplifier’s power switch. When the switch is
ON, the LED lamp of the channel currently selected with the CH SE-
LECT switch will light.
Power Requirements : U.S. and Canadian models : 120V, 60Hz
General model : 230V, 50Hz
Dimensions (W x H x D) : 357 x 330 x 197 mm (14.1" x 13" x 7.8")
Weight : 6.5 kg (14 lbs 5 oz)
GUITAR AMPLIFIER
Owner’s Manual
* Specifications and external appearance are subject to change without notice.
w e r t y u i o !0 !1q

Yamaha F-20 Specifications

General

Power Output	20W
Type	Guitar Amplifier
Technology	Solid State
Speaker Size	8 inches
Controls	Gain, Middle, Bass
Inputs	1 x 1/4" (Guitar Input)
Outputs	1 x Headphones (1/4" jack)

Summary

Precautions

General Operational Precautions

Avoid direct sunlight, extreme temperatures, humidity, dust, and neon lighting.

Vehicle Precautions

Do not leave the amplifier in a parked car on a sunny day due to excessive heat.

Electrical Safety Precautions

Set volume to 0 before connecting/disconnecting or turning on/off.

Handling and Care

Handle carefully, avoid excessive force, dropping, and tampering with internal circuitry.

Cleaning Instructions

Wipe clean with a soft, dry cloth; avoid solvents like benzene or thinner.

Specifications Overview

Control Panel Functions

Input Jack

Connect your guitar to this jack for input signal.

Channel Select Switch (A/B)

Switch between clean (raised) and distorted (depressed) channels.

Channel A Volume

Controls volume for Channel A when selected.

Channel B Gain

Controls distortion level for Channel B when selected.

Master Volume

Controls volume for Channel B when selected.

Tone Controls

Adjusts Treble, Middle, and Bass frequencies for sound shaping.

Auxiliary Input

Connect external audio devices for playback with guitar.

Headphone Jack

Connect headphones; speaker sound is muted when used.

Power Switch

Turns the amplifier on/off; indicator lamp shows selected channel.

Important Safety Instructions

General Safety Rules

Read manual, do not service beyond instructions, verify supply voltage, and ground properly.

Cord and Placement Safety

Avoid cord damage, tripping hazards, and do not use extension cords unless specified.

Ventilation and Temperature

Ensure proper ventilation and avoid placement near heat sources.

Environmental Hazards

Do not use in wet/damp locations, near water, or expose to rain.

Accessory and Lightning Safety

Use recommended accessories and disconnect power during lightning.

Object/Liquid Entry

Prevent objects from falling or liquids spilling into openings.

Servicing Requirements

Refer servicing to qualified personnel for damaged cords or enclosure issues.

Hearing Protection

Avoid prolonged high volume levels to prevent permanent hearing loss.

Accessory Installation

Ensure benches and mounting fixtures are stable and secure.

United Kingdom Specific Notice

UK Plug and Cord Connection

Instructions for connecting the mains lead wires (Green/Yellow, Blue, Brown) to UK plug terminals.