The service manual for the Hammarlund HQ-110A/VHF and HQ-170A/VHF covers the setup and operation of these receivers, detailing how to tune them for amateur frequencies from 160 meters through 2 meters, and includes instructions for receiving CW, AM, and SSB signals. It also provides troubleshooting information, such as improving sensitivity on the 6-meter band with a low noise pre-amplifier, and guidelines for antenna connections and alignment procedures.
Manual Overview
The Hammarlund HQ-110A/VHF and HQ-170A/VHF service manual provides detailed instructions for troubleshooting, diagnostics, calibration, and adjustments for technicians. The manual emphasizes the importance of using a suitable antenna and provides guidance on antenna connections, noting that separate antennas are recommended for 6 and 2-meter operations. The manual outlines the operation of the 6-meter pre-amplifier and 2-meter converter, highlighting the use of 6CW4 Nuvistor tubes and a crystal-controlled oscillator for frequency conversion.
For troubleshooting, the manual includes a field alignment procedure requiring a signal generator and alignment tools. Technicians are instructed to adjust various coils and capacitors to optimize signal reception. The manual also describes the use of a relay to isolate the 6-meter antenna and prevent signal leakage. Additionally, it provides a schematic diagram and parts list for board-level repairs and adjustments. The manual stresses the importance of following the recommended alignment procedures to maintain optimal performance and prevent spurious responses.
Quick Issues Covered
- Diagnose power-up failures with volume control and bandswitch settings.
- Calibrate 2-meter converter using L207 and L208 adjustments.
- Trace circuits using detailed schematic for HQ-110A/VHF model.
Overview
The Hammarlund HQ-110A/VHF and HQ-170A/VHF are receivers designed to tune all amateur frequencies from 160 meters through 2 meters, providing reception for CW, AM, and SSB signals. The manual covers the operation of these receivers, including the use of a low noise 6CW4 pre-amplifier stage for improved sensitivity on the 6-meter band, and the conversion of 144 to 148 Mc signals to 50 to 54 Mc signals. It also provides detailed instructions on the theory of operation, field alignment procedures, and modifications for antenna and crystal calibrator circuits.
Specifications
- HQ-110A/VHF and HQ-170A/VHF Receivers
- – Tunes all amateur frequencies from 160 meters through 2 meters
- – Reception of CW, AM, and SSB signals
- – 6CW4 pre-amplifier stage for improved sensitivity on 6 meter band
- – Crystal controlled oscillator using a 31.333 Mc crystal
- – Output on 94 Mc
- – 2 meter converter and 6 meter pre-amplifier circuit
- – Uses (4) type 6CW4 Nuvistor tubes
- – Bandpass filter with components L202, C204, C206, L203, L204
- – Broadband filter approximately 5 Mc wide
- – Series trap tuned to 188 Me
- – Tunable neutralizing coil L211
Controls & Indicators
Refer to the PDF for details.
Installation / Setup
Refer to the PDF for details.
Operation
To receive 6 meter signals (50 to 54 Mcs), place the bandswitch in the 50 to 54 Mc position and push in the volume control knob. Connect a suitable antenna to the proper antenna terminal. For improved sensitivity on the 6 meter band, a low noise 6CW4 pre-amplifier stage is used. When the bandswitch is in the 50 to 54 Mc position and the volume control knob is pulled out, frequency converter stages are activated to change 144 to 148 Mc signals to 50 to 54 Mc signals. It is recommended to push in the volume control knob when not receiving 2 meter signals to reduce power consumption. Separate antennas are recommended for 6 and 2 meter operation, and a switching unit should be used if a combination 6/2 meter antenna is desired. On 6 and 2 meters, the sideband switch is reversed due to the high frequency oscillator, resulting in the upper sideband being received in the lower sideband position and vice versa.
Troubleshooting & Error Codes
Refer to the PDF for details.
Safety & Warnings
Refer to the PDF for details.
Download MANUAL Service manual (PDF – 480.0 KB)
Service manual for Hammarlund HQ-110A Converter Preamp; assists technicians in troubleshooting and calibrating the device. File size: 480.0 KB.
- Brand: Hammarlund-hq-110a-converter-preamp-service
- Model: MANUAL
- Type: Service manual
- File size: 480.0 KB
Overview
Brief overview of the product.
Specifications
- Key spec 1
- Key spec 2
Controls & Indicators
Control panel/button layout.
Installation / Setup
- Step 1…
- Step 2…
Operation
Basic usage, modes, cycles.
Troubleshooting & Error Codes
| Issue / Code | Fix |
|---|---|
| Example | How to fix… |
Safety & Warnings
- Important warning…
Downloads
Download MANUAL service manual (PDF)
Hammarlund HQ-110A Converter Preamp Service Manual Overview
The Hammarlund HQ-110A Converter Preamp is a specialized piece of vintage radio equipment designed to enhance signal reception by converting and amplifying weak radio frequency signals. Primarily used in communication and amateur radio setups, this device improves audio clarity and sensitivity, enabling users to receive distant or low-power transmissions with greater fidelity.
Main Features and Specifications
- Frequency conversion capability for improved signal selectivity
- High-gain preamplifier stage to boost weak signals
- Robust construction suitable for long-term use
- Compatible with a wide range of radio receivers
- Adjustable gain control for optimal signal strength
- Low noise design to maintain signal integrity
Basic Usage and Operation Tips
To operate the HQ-110A Converter Preamp effectively, connect it between your antenna and receiver input. Adjust the gain control gradually to avoid signal distortion or overload. Ensure all connections are secure and use shielded cables to minimize interference. Regularly monitor the output signal strength and fine-tune settings to achieve the best reception quality.
Troubleshooting and Maintenance
If you experience weak or distorted signals, first check all cable connections for damage or looseness. Inspect the unit for signs of wear or component failure, such as burnt resistors or capacitors. Clean contacts and connectors periodically to prevent oxidation. Refer to the service manual’s schematic diagrams for detailed repair procedures. Always power down the device before performing any maintenance.
Safety Reminder
When servicing or operating the HQ-110A Converter Preamp, ensure the device is disconnected from power sources to prevent electric shock. Avoid exposure to moisture and extreme temperatures. Use proper tools and follow recommended safety practices outlined in the manual to protect both the equipment and yourself.
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