The Kenwood SM-220 service manual provides detailed instructions for setting up, operating, and troubleshooting the station monitor, including specifications, circuit descriptions, and adjustment procedures. It also includes safety warnings regarding high voltages and handling the high vacuum CRT, as well as optional pan display units for specific transceiver series.
Manual Overview
The Kenwood SM-220 service manual provides detailed instructions for technicians servicing the station monitor. Key sections include troubleshooting, error codes, diagnostics, calibration, and adjustments. The manual emphasizes safety, highlighting the risks associated with high voltages and the fragile nature of the CRT. Troubleshooting guidance is found in Section 12, which outlines systematic approaches to diagnosing and resolving issues, though specific error codes are not detailed. Calibration and adjustment procedures are covered in Section 11, including adjustments for horizontal trace tilt and two-tone oscillator balance. The manual includes board-level guidance in Section 7, detailing printed circuit board layouts and components. For disassembly, Section 10 provides step-by-step instructions, including diagrams for removing the front panel and CRT. The manual also includes schematics in Section 14 for detailed circuit analysis. Overall, the manual serves as a comprehensive resource for maintaining and repairing the SM-220, ensuring technicians can effectively address both routine maintenance and complex repairs.
Quick Issues Covered
- Diagnose power-up failures with troubleshooting section guidance.
- Calibrate horizontal trace tilt without case removal.
- Use schematics for detailed circuit tracing and repairs.
Overview
The SM-220 Station Monitor is designed for use with the TS-820 and TS-520 series SSB transceivers. It functions as a monitor scope, oscilloscope, and two-tone oscillator, with an optional Pan Display scope function available. The device allows for the observation of transmit waveforms from 1.8 to 150 MHz and supports power levels of 2KW PEP to 54 MHz and 200W PEP to 150 MHz. It features a blue-green phosphor CRT for excellent brightness and contrast, and offers oscilloscope sensitivity of 20 mV/div with a bandwidth of 2 Hz to 10 MHz. The manual covers specifications, features, CRT specifications, block diagram, circuit description, views, printed circuit boards, parts list, packing, disassembly, adjustment, troubleshooting, pan display option, and schematics.
Specifications
- CRT75ARB31
- Phosphor: B31
- COMOUE: Blue-Green
- TRANSMIT SIGNAL MONITOR TERMINAL
- Frequency range: 4.8 ~ 150 MHz
- Maximum power: 1.8 ~ 54 MHz (2 kW/PEP), 150 MHz (200 W/PEP)
- SWR: 1.2 or less
- Deflection sensitivity: More than 1 DIV at 2 W/PEP input
- Attenuator: 6 steps
- TRAPEZOID WAVEFORM OBSERVATION
- Frequency range: 1.8 ~ 30 MHz
- Maximum power at DRIVE terminal: 100 W/PEP
- SWR: 1.2 or less
- TWO-TONE GENERATOR
- Oscillator frequency: 1,000 Hz 1575 Hz or both switchable
- Output voltage: 10 mV/50k2 (at TWO TONE)
- PAN DISPLAY
- Adaptor name: BS-5 (TS-5 20 series), BS-8 (TS-820 series)
- Input center frequency: 3,395 MHz (BS-5), 8.830 MHz (BS-8)
- IF frequency: 455 kHz
- VF bandwidth: More than 1 kHz(—6 dB)
- Input sensitivity: More than 20 dB p/DIV
- Scan width: +20 kHz, +100 kHz, selectable
- HORIZONTAL AMPLIFIER
- Gain adjustment: 100B (Approximate)
- Deflection sensitivity: More than 300 mvV/DIV
- Frequency response: DC-250 kHz or greater (EXT GAIN at MAX), DC-40 kHz (EXT GAIN at 1/2)
- Input resistance/capacity: 1 MQ(+20%), 40 pF or less (SYNC switch at INT)
- Attenuator: Fully variable to 0
- Max. input voltage: 100 Vp-p
- SWEEP CIRCUIT
- Sweep frequency: 10 Hz ~ 100 kHz (in 4 ranges, variable)
- Sweep linearity: Better than 5%
- Sync system: Synchronized sweep, internal negative sync and external sync
- Sync amplitude: Internal… More than 1 DIV on CRT, External … More than 2 Vp-p
- VERTICAL AMPLIFIER
- Deflection sensitivity: More than 20 mV/DIN
- Frequency response: 2 Hz ~ 10 MHz (—3 dB)
- Input resistance/capacity: 1 MQ, 40 pF
- Overshoot: Less than 5%
- Attenuator: 1, 1/10, 1/100 and GND/MONITOR (Error between steps: 5% max.)
- Max. input voltage: 300V (DC-+AC peak) or 600 Vp-p
- POWER SUPPLY: AC 117V +10%, 50/60 Hz, 20W
- DIMENSIONS: 215(W) x 153(H) x 335(D)mm
- Weight: 5 kg
- ACCESSORIES SUPPLIED
- Instruction book: 1
- VHF type cable: 1
- Tone output cable: 1
- Auxiliary feet (with screws): 2
- Warranty card: 1
Controls & Indicators
Refer to the PDF for details.
Installation / Setup
Refer to the PDF for details.
Operation
Refer to the PDF for details.
Troubleshooting & Error Codes
Refer to the PDF for details.
Safety & Warnings
The manual includes the following safety warnings and precautions:
1. High Voltages Present: It is important to observe all standard safety procedures regarding high RF, AC, and DC potentials to prevent personal injury.
2. High Vacuum CRT: The CRT (cathode ray tube) in the instrument is a high vacuum device. Breakage may cause high velocity scattering of glass particles, so rough handling of the instrument, especially the CRT, should be avoided.
Download MANUAL Service manual (PDF – 1.5 MB)
Kenwood SM-220 Service Manual: Troubleshoot and calibrate the SM-220 model efficiently. PDF size: 1.5 MB.
- Brand: Kenwood-sm-220-service
- Model: MANUAL
- Type: Service manual
- File size: 1.5 MB
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)
Kenwood SM-220 Service Manual Overview
The Kenwood SM-220 is a professional-grade audio signal monitor designed for precise measurement and analysis of audio signals in broadcasting and recording environments. This device allows technicians and engineers to ensure optimal sound quality by providing accurate level monitoring, signal integrity checks, and fault diagnostics. The service manual offers detailed instructions for maintenance, repair, and calibration to keep the SM-220 operating at peak performance.
Main Features and Specifications
- High-precision audio level monitoring with LED and meter display
- Wide frequency response for accurate signal analysis
- Multiple input options including balanced and unbalanced connections
- Compact and durable design suitable for studio and field use
- Built-in calibration controls for easy adjustment and maintenance
- Low noise circuitry ensuring minimal signal distortion
Basic Usage and Operation Tips
To use the Kenwood SM-220, connect the audio source to the appropriate input terminals, ensuring correct polarity and impedance matching. Power on the device and observe the signal levels on the LED indicators and analog meter. Adjust input gain controls as necessary to maintain optimal levels without clipping. Regularly calibrate the unit using the built-in controls to ensure measurement accuracy. Always allow the device to warm up for a few minutes before critical measurements.
Troubleshooting and Maintenance Notes
If the unit fails to power on, first check the power supply and fuse condition. For erratic meter readings or signal loss, inspect input connections and cables for damage. Clean the connectors periodically to prevent oxidation. Calibration drift can be corrected by following the calibration procedure outlined in the manual. Avoid exposing the device to extreme temperatures or moisture to prolong its lifespan.
Safety Reminder
Always disconnect the Kenwood SM-220 from the power source before performing any maintenance or repair. Use only specified replacement parts to avoid electrical hazards. Operate the device in a well-ventilated area and avoid contact with water or conductive materials. Following these safety precautions will help prevent injury and equipment damage.