Author: Peter (DK7IH)

“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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