HQT TH-2800 - User Manual

TH-2800 Turn up procedure
It can either use PC program software or manual tuning mode to debugging TH-2800.The
Following method is the latter one. (see“TH-2800 function” , manual tuning mode ）。
1. Equipment:
1． One comprehensive tester
2． One scanner
3． One 3A/10V power source
4． One digital voltmeter
5． One 3A Ammeter
2. User Mode
Press PTT key to transmit, speak to the microphone with normal voice. Please
keep 2.5 to 5 center meters away from your mouth and the microphone.
Release PTT key when receiving.
3. Mode Setting
1. Short-circuit two points of SELF on PCB，turn on the radio, LED flashes red and
green in turns.
2. Choose channel according to its model.
3. Manual tuning function and wired clone function will be switched on
automatically.
4. Press PTT key, then set the current chosen channel, system initialization starts.
Note:
Once the radio has been re-initialized, the pre-stored tuning data and channel
information (frequency, CTCSS/CDCSS) will be erased and some function may changes, too.
Therefore try to avoid this operation unless replacing E2PROM and other necessary setting.
4. Wired Clone Mode
(1) Press SK2 key on the source radio to turn on it, LED will then flashes twice in red
in 2 seconds, which means the radio entered wired clone mode.
(2) The target radio needs to be enabled with clone mode by pressing PTT key while
the main radio is still in the clone mode. To disable the clone function of the target
radio, press [PTT] key again and the indicator flashes red twice. The clone
function of target radio is disabled as default.
(3) Press SK2 key on the source radio, when the red light starts to flash it means it is
in the process of clone. When it is finished the red light goes off. If it’s failed, the
indicator flashes in green instead of red.
Note: The wired clone mode can be disabled through using programming
software.

Summary

Equipment Requirements

User Mode Operation

Transmit and Receive Procedure

How to transmit using the PTT key and speak into the microphone at a specific distance.

Mode Setting Configuration

Initialization and Mode Switching

Steps for short-circuiting PCB points, powering on, and setting up modes like manual tuning and wired clone.

Wired Clone Mode Transfer

Source and Target Radio Setup

Procedure to enable wired clone mode on source and target radios and initiate data transfer.

Manual Tuning Mode Guide

Entering Manual Tuning Mode

Steps to enter manual tuning mode by pressing PTT+Moni and observing LED flashes.

7.5 V Voltage Calibration

Procedure for calibrating the 7.5V voltage supply, involving channel selection and power-on sequences.

Manual Turn Up Switch On;Off

Steps to switch the radio on/off in manual tuning mode, involving channel selection and adjustment.

Initialization Procedure

Procedure for initializing the radio within manual tuning mode, involving specific channel and power-on sequences.

Aging Program Setup

Steps to enter and configure the aging program, involving channel selection and observing indicator lights.

Communication Setting Adjustments

Adjusting Tx Frequency, Deviation, CTCSS, and CDCSS deviation using PTT and MONI buttons.

VHF Power Adjustments

Procedure to adjust VHF power levels (high and low) across different frequency bands.

UHF Power Adjustments

Procedure to adjust UHF power levels (high and low) across different frequency bands.

VHF SQL Adjustments

Steps to adjust the VHF squelch (SQL) level using channel selection and button presses.

UHF SQL Adjustments

Steps to adjust the UHF squelch (SQL) level using channel selection and button presses.

Overview

1. Function Description
2. Usage Features
3. Basic Operation (User Mode)
4. Mode Setting
5. Wired Clone Mode
6. Manual Tuning Mode
7. Manual Tuning Steps (Detailed)
8. Maintenance Features
9. Pre-Manual Tuning Preparation
10. System Initialization Caution
11. Disabling Wired Clone Mode

This document outlines the procedures for setting up and maintaining the TH-2800 device, focusing on both user-level operation and more advanced manual tuning and cloning functionalities.

Function Description

The TH-2800 is a communication device that can be configured either through PC program software or via a manual tuning mode. This manual specifically details the latter, providing a step-by-step guide for its operation and adjustment. The device supports basic user communication, allowing transmission and reception, and offers advanced modes for calibration, programming, and cloning. It is designed to allow for precise adjustments of various parameters, including frequency deviation, power output, sensitivity, and noise elimination, ensuring optimal performance. The device also incorporates features for system initialization and an aging program, which are crucial for its long-term reliability and proper functioning.

Usage Features

Basic Operation (User Mode):

To transmit, the user simply presses the PTT (Push-To-Talk) key and speaks into the microphone. It is recommended to maintain a distance of 2.5 to 5 centimeters between the mouth and the microphone for clear communication. Releasing the PTT key switches the device back to receiving mode. This straightforward operation makes the TH-2800 accessible for general communication tasks.

Mode Setting:

Before advanced operations, the device needs to be put into a specific mode. This involves short-circuiting two points labeled "SELF" on the PCB and then turning on the radio. During this process, the LED indicator will flash red and green alternately, signaling entry into the mode. The user then selects the appropriate channel based on the device's model. Once in this mode, manual tuning and wired clone functions are automatically enabled. Pressing the PTT key at this stage sets the currently chosen channel and initiates a system initialization. It's important to note that re-initializing the radio will erase pre-stored tuning data and channel information (frequency, CTCSS/CDCSS) and may alter some functions. Therefore, this operation should generally be avoided unless replacing the E2PROM or performing other necessary settings.

Wired Clone Mode:

The TH-2800 supports a wired clone mode, allowing the transfer of settings from a "source" radio to a "target" radio. To activate this mode on the source radio, the SK2 key is pressed while turning on the device. The LED will flash red twice within 2 seconds, indicating that the source radio has entered wired clone mode. For the target radio to receive the clone, it must also be enabled for clone mode by pressing its PTT key while the source radio is still in clone mode. To disable the clone function on the target radio, the PTT key is pressed again, and the indicator will flash red twice. By default, the clone function on the target radio is disabled. During the cloning process, pressing the SK2 key on the source radio will cause the red light to flash, signifying that cloning is in progress. Once completed, the red light will turn off. If the cloning process fails, the indicator will flash green instead of red. This wired clone mode can also be disabled using programming software.

Manual Tuning Mode:

The manual tuning mode is designed for adjusting critical parameters such as frequency deviation, power output, sensitivity, and noise elimination. To enter this mode, the user must press the [PTT+Moni] keys simultaneously while turning on the power. These keys should be held for 2 seconds until the LED flashes green twice, after which they can be released, and the device will enter manual tuning mode.

Manual Tuning Steps (Detailed):

• 7.5V Voltage Calibration: This involves switching to channel 1, connecting a 7.5V power source, and then powering on the device by pressing [PTT] and the [Middle key] simultaneously. The red light will illuminate. Subsequently, switching to channel 16 within 4 seconds will complete the calibration, indicated by a long "Di" sound.
• Manual Turn Up Switch On/Off: To enable this, switch to channel 1 and press [PTT+MONI] to turn on, with the green light illuminating. To switch it off, switch to channel 16 within 3 seconds. Adjustments can be made by pressing [PTT] or [MONI], with a long "di" sound indicating "on" and a short "di" sound indicating "off."
• Initialization: Switch to channel 8 and press [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light.
• Aging Program: Switch to channel 10 and press [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light and turn on the red light, indicating entry into the aging program.
• Communication Setting: Switch to channel 11 and press [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light. Further adjustments for Tx Frequency, Deviation, CTCSS, and CDCSS deviation are made by switching to specific channels (15, 14, 13) and using the PTT key for increasing values and the MONI key for decreasing values.
• VHF Power Adjust: This involves switching to channel 12 and pressing [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light and turn on the red light. High power in low frequency is adjusted on channel 16, high power in high frequency on channel 15, low power in low frequency on channel 14, and low power in high frequency on channel 13.
• UHF Power Adjust: Similar to VHF power adjustment, this involves switching to channel 13 and pressing [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light and turn on the red light. High power in low frequency is adjusted on channel 16, high power in high frequency on channel 15, low power in low frequency on channel 14, and low power in high frequency on channel 13.
• VHF SQL Adjust: Switch to channel 14 and press [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light. Adjustments are made with [PTT] on and [MONI] off, with a step of 5MHz.
• UHF SQL Adjust: Switch to channel 15 and press [PTT+MONI] to turn on, with the green light illuminating. Switching to channel 16 within 3 seconds will turn off the green light. Adjustments are made with [PTT] on and [MONI] off, with a step of 10MHz.

Maintenance Features

Pre-Manual Tuning Preparation:

Before entering manual tuning mode, it is crucial to read the radio settings into a computer using the programming software. This data should then be used to program the manual and modulation modes, selecting manual tuning mode. After closing the current window, the modulated settings from the computer should be written back to the radio. This preparatory step is essential to enable entry into the manual tuning mode and ensure that existing configurations are preserved or correctly updated.

System Initialization Caution:

As mentioned, performing a system initialization will erase all pre-stored tuning data and channel information (frequency, CTCSS/CDCSS) and may alter some device functions. Therefore, this operation should be undertaken with caution and only when absolutely necessary, such as when replacing the E2PROM or performing other critical settings that require a fresh start. This highlights the importance of understanding the implications of such actions to avoid unintended data loss or configuration changes.

Disabling Wired Clone Mode:

While the wired clone mode offers convenience for transferring settings, it can also be disabled if not required or for security reasons. The manual specifies that the wired clone mode can be disabled through the use of programming software, providing a flexible option for managing this feature.

The TH-2800 is designed with both ease of use for basic communication and comprehensive adjustment capabilities for advanced users and technicians, ensuring its adaptability and performance across various operational requirements.

HQT TH-2800 Specifications

General

Frequency Range	400-470MHz
Number of Channels	16
Output Power	5W
Operating Voltage	7.4V
Battery	1500mAh (Li-ion)