Category: homebrew

Revising the “Lean Design Transceiver”

  The “Lean Design Transceiver” has been a project to build a simplified but effective 100% analog SSB QRP transceiver with minimum effort. The radio worked fine but there is never anything that can not be improved. So, this transceiver, originally built in 2018, also has been scheduled for a revision. The problems were minor, …

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“Gimme Five” reloaded – A compact 5 band QRP SSB transceiver in SMD technology – TRANSMITTER spectrum analysis

Abstract The 10 watts peak envelope power linear transmitter for single sideband operation will be examined. Test conditions are: 10 watt pep on every band, rf line terminated with 50 ohm dummy load, input audio two-tone signal identically applied for each measurement. Measurements have been taken with RIGOL DSA815 spectrum analyzer, RIGOL DS1054 digital oscilloscope…

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“Gimme Five” reloaded – A compact 5 band QRP SSB transceiver in SMD technology: VFO, LO, MCU etc.

As mentioned in the introductory article to this radio the digital components in this transceiver are pre-manufactured modules that have only been put together in a more or less sensible way. ;-). These modules are: AD9850 as variable frequency oscillator (VFO), China made no-name board, Si5351 as local oscillator (LO) produced by “Adafruit”, Arduino Pro…

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“Gimme Five” reloaded – A compact 5 band QRP SSB transceiver in SMD technology

Follow-up articles published so far: Digital and analog main units: VFO, Local oscillator, Display, TX-Gain control Receiver unit Transmitter unit Abstract A compact SSB transmitter/receiver will be presented. This unit covers 5 bands within the amateur radio spectrum (3.5, 7, 14, 21 and 28 MHz). Receiver is a single conversion unit with an interfrequency of…

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Mixer comparison: “NE612” vs. “AN612”

Abstract The well-known mixer NE612 (NXP) will be compared to an AN612 (Matsushita/Panasonic) mixer that has been unsoldered from an old CB-SSB-radio. Comparison will include output voltage level and spectroscopic analysis of a 9MHz SSB signal. The NE612 When we talk about about integrated double balanced mixers (DBM) and say the number “612” we usually…

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