Projects for the amateur radio engineer. Hardware, software, electronics and test equipment for the amateur community.
by Peter Baier (DK7IH) After years of indoor model-railroading I have started building a medium-sized garden railroad this spring after having completely redesigned our garden by removing trees and therefore getting space for the railroad layout. Normally model trains are track-powerd. For outdoor operation this is not the best idea because due to weathering tracks’…
Chapter 1: General design and oscillator circuits (This posting) Chapter 2: Receiver (coming soon) Chapter 3: Transmitter (coming soon) Chapter 4: Cabinet, frequency counter, antenna etc. (coming soon) Chapter 5: Final remakrs (coming soon) This radio also is some sort of “rebuilt”. in 2015 I developed a handheld transceiver with about 5 watts of output…
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, …
When the project of building a very small transceiver was accomplished 4 years ago, I still lacked lots of skills in setting up electronic circuits using SMD technology. The radio’s craftmanship had been more or less defective to a certain degree (there were still lots of things to learn when using SMDs on Veroboards), the…
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…
Abstract This article will describe some design ideas that might be helpful in case the objective is building a medium power (i. e. 10 to 20 watts pep) radio frequency amplifier using a very compact design The whole final amplifier for the broadband linear transmitter had to be packed into an area whose size is …
Abstract The transmitter for this transceiver is designed to deliver a peak envelope power (PEP) of 10 watts on all bands from 80 to 15 meters. Due to its purpose (SSB amplification) it is a linear amplifier. The circuit is equipped with 5 stages where the first one is a gain control stage containing a…
Sorry for having deferred the description of the transmitter. The recent days I have been concerned with a new frequency layout for the transceiver. I found that the 17m-band could be an interesting topic because when tuning on internet based SDR pages the last days I saw many strong signals appearing. This might be due…
Introductory article of this project This is some sort like “Copy & Paste”, a useful mean if you want to create a doctorate, like the former German Minister of Defense Mr Guttenberg once did. 😉 I don’t want to achieve a doctorate but the receiver of this radio is more or less the same I…
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…