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CwGet v2.55 is a software application designed for amateur radio operators to decode Morse code (CW) signals into text using a standard computer sound card, eliminating the need for specialized hardware. The program features a customizable interface with three primary windows: a spectrum display for visualizing signal frequencies and peaks, an oscillogram for monitoring signal presence and setting detection thresholds, and a received symbols window for displaying decoded text. Key functionalities include Automatic Frequency Control (AFC) to lock onto signals, adjustable FIR and IIR filters for noise reduction, and a burst filter to mitigate short noise impulses. It also supports automatic CW speed detection, multiple character sets, and the ability to record and replay received audio. Integration with logging software like AALog is facilitated through double-click word transfer, and transceiver frequency control is possible via the Omni-Rig interface, allowing for automatic tuning of the radio's VFO or RIT. The multi-channel decoder feature can simultaneously decode up to five strong signals within a 1600 Hz bandwidth, displayed in a separate Multi-RX Window with an adjustable squelch. CwGet also offers the capability to decode signals from pre-recorded WAVE files and can function as a narrow-band sound DSP filter for aural decoding. Configuration options are saved to an INI file, supporting multiple setups for different operating scenarios.

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

The 2.1 kHz wide European LF allocation between 135.7 and 137.8 kHz is detailed in this observed band plan, offering guidance for activity within this narrow segment. It specifically addresses the challenge of locating weak signals, such as those from Slow-CW stations, which can have bandwidths of only a few Hertz. The resource emphasizes the utility of precise frequency knowledge when operating with narrow DSP filters, like a 30 Hz filter for CW, to differentiate multiple stations within a very small band segment. The plan, though not officially recognized, provides practical orientation for operators, particularly those new to the _LF band_. It references a similar plan published by the _RSGB_ in the January 2000 issue of _RADCOM_, suggesting a community-driven approach to band organization. The content highlights the importance of spectral awareness, noting that multiple stations can occupy minimal bandwidth, a concept illustrated by spectrographic analysis.

Sherwood Engineering Inc., based in Denver, Colorado, specializes in ham radio accessories and components. The company, located at 1268 South Ogden Street, offers a variety of products including filters, cooling kits, and audio switch boxes. Sherwood Engineering is known for its work with brands such as _Drake_, _Icom_, and Collins, providing components like 455 kHz mechanical and crystal filters. The company has also been involved in producing first-IF roofing filters and DSP protection filters. Sherwood Engineering has a history of over 45 years in the industry, though it has now retired from producing certain products like the SE-3 MK IV. Despite this, the company continues to provide technical resources and presentations on optimizing rig performance, with past events held at venues like the Dayton Contest University in 2014. The company operates Monday through Friday, from 9 a.m. to 5 p.m. Mountain Time, and accepts payments via PayPal, check, or money order. DXZone Focus: Denver | Filters | Icom

The Yaesu FT-1000MP Mark-V, introduced at Dayton 2000 Hamvention, features a higher RF power of **200 W PEP** and a Class-A amplification SSB mode at 75 W. Key enhancements include an _Interlocked Digital/Analog Bandwidth Tracking system (IDBT)_, a Variable Front-End Filter (VRF) preselector, and improved ergonomics, notably a multi-function shuttle jog dial. This model, a successor to the 1996 FT-1000 and FT-1000MP, was designed to compete with high-end transceivers, despite its retail price of $4200 initially. The transceiver's physical dimensions are 406 x 135 x 348 mm (16 x 5.3 x 13.7 inches) with a weight of 14 kg (31 lbs), making it substantial. Its rear panel offers over 20 connections, including power, external DSP speaker, BAND DATA I/O, ALC, and multiple interface jacks for DVS-2, Packet, and RTTY. The unit also provides two keyer inputs, a DB9M serial interface for CAT, and two PL female antenna connectors, plus additional receive antenna jacks. Despite its advanced internal architecture, including two independent receivers with their own IF filters and AGC loops, the display technology, utilizing fluorescent discharge rather than LCD, contributes to an older aesthetic. The control panel is extensive, featuring 92 knobs and buttons, alongside numerous LED indicators for various modes and functions.

Replacing filters on ICOM IC 775

Constructing a dip oscillator provides radio amateurs with a fundamental piece of test equipment for resonant circuit analysis. This particular design, adapted by VK3YE from a concept by _Drew Diamond VK3XU_, details a practical build using readily available components. The unit incorporates four plug-in coils, covering a frequency range from **2.6 MHz to 55 MHz**, mounted on 5-pin DIN plugs for versatility. A salvaged two-gang air dielectric variable capacitor, fitted with a vernier reduction drive, serves as the tuning mechanism, with the smaller gang optimizing bandspread at higher frequencies. In practical application, the dip oscillator is used by setting the meter needle to approximately two-thirds scale. When the instrument's coil is brought near a tuned circuit under test, a noticeable dip in the meter reading indicates resonance. This allows for precise measurement of resonant frequencies in antennas, filters, and other RF circuitry, proving invaluable for homebrewing and troubleshooting. The design emphasizes short wire runs for stable operation, particularly at the higher end of its operational range.

Icom IC-R9500 Professional Receiver with 5 roofing filters, 48 kHz DSP

The ICOM IC-R75, introduced in 1999, operates on 13.6 Volts DC and measures 241 by 94 by 229 mm. Its coverage spans from 30 kHz to 60 MHz, making it a versatile receiver for various bands. The review details available accessories, including optional filters and the **UT-106 DSP module**, which significantly enhances signal processing capabilities. Performance comparisons are drawn against other notable receivers such as the Drake R8B and earlier ICOM models, providing context for its audio quality and overall functionality. User feedback is integrated, offering practical insights into its daily operation and reception characteristics across the spectrum. This analysis offers an in-depth look at the IC-R75's technical capabilities and features, serving as a valuable reference for operators interested in this **legacy receiver**.