The manual for Drake 048 provides detailed instructions on setting up, operating, and troubleshooting the AC4/AC3 power supply, emphasizing safety precautions due to the presence of high voltages. It includes procedures for verifying voltages, diagnosing issues with components such as diodes and capacitors, and offers guidance on replacing faulty parts to ensure proper functionality.

• Brand: Drake
• Model: 048
• Type: manual
• File size: 536.4 KB

Manual Overview

The manual for the Drake 048 AC4/AC3 power supply focuses on troubleshooting procedures, diagnostics, and adjustments. It begins with a warning about high voltages and outlines a two-step troubleshooting process. The first step involves verifying voltages at the connector, while the second requires removing the bottom cover if necessary. The power supply is divided into AC and DC sections, with specific voltages supplied to various parts of the radio. The manual provides detailed instructions for simulating the power switch and measuring voltages using a DC voltmeter. It emphasizes checking for minimal AC voltage to ensure filter capacitors are functioning correctly. If issues are detected, the manual advises inspecting and replacing burnt components, diodes, and filter capacitors, with specific recommendations for replacements. It also notes common problems such as overheating of resistor R3 and capacitor failures. Additional resources for retrofitting and refurbishing are suggested, and the manual highlights the interchangeability of the AC4 and AC3 models.

Quick Issues Covered

• Diagnose AC4/AC3 power-up failures by shorting pins #1 & 2.
• Verify DC voltages at connector pins for troubleshooting power supply issues.
• Use schematics for circuit tracing and component location in AC4/AC3.

Overview

Refer to the PDF for details.

Specifications

“”

Controls & Indicators

Refer to the PDF for details.

Installation / Setup

Refer to the PDF for details.

Operation

The operation of the AC4/AC3 power supply involves verifying voltages at the connector and potentially removing the bottom cover for further testing if needed. The power supply is divided into AC and DC sections, with separate sections supplying different voltages: the High Voltage (HV) section provides approximately +650 volts, the Low Voltage (LV) section provides approximately +250 volts, the Bias supply provides negative bias voltage, and the filament supply provides AC voltage to the tubes. To power up the AC4/AC3, short pins #1 and #2 to simulate the power on/off switch inside the radio. Use a DC volt meter to verify the presence of DC voltage at various pins, ensuring minimal AC voltage is present. If issues are detected, troubleshooting steps include checking for burnt components, replacing diodes, and inspecting filter capacitors for leakage or failure.

Troubleshooting & Error Codes

Refer to the PDF for details.

Safety & Warnings

In the following procedures you will be close to dangerous high voltages. Be careful. Unplug the supply from the outlet. When performing the following step, make sure that if you do not see a voltage within several seconds, you unplug the supply immediately. In each of the following steps, you can choose to unplug the supply after each step. This will prevent damage to components while you are checking other sections. If a problem is noted in any of the above steps, unplug the unit from the AC outlet. Unplug the AC4 and let it sit for several minutes before proceeding.

Download 048 Manual (PDF – 536.4 KB)

Troubleshoot Drake AC-3/AC-4 power supply issues for model 048 with step-by-step guidance in this 536.4 KB PDF manual.

• Brand: Drake-ac-3-ac-4-power-supply-trouble-shooting-tie
• Model: 048
• Type: Manual
• File size: 536.4 KB

Overview

Brief overview of the product.

Specifications

• Key spec 1
• Key spec 2

Controls & Indicators

Control panel/button layout.

Installation / Setup

1. Step 1…
2. Step 2…

Operation

Basic usage, modes, cycles.

Troubleshooting & Error Codes

Safety & Warnings

• Important warning…

Downloads

Download 048 manual (PDF)