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2023 Chinese New Year Closing Notice
Fujian Shengda Communications Co., Ltd. would like to inform the public that its office will be closed during the Chinese New Year holidays from 17th January 2023 and will resume business on 29th January 2023. We Apologize for Any Inconvenience Caused.ادامه مطلب -
2022 Chinese New Year Closing Notice
Fujian Shengda Communications Co., Ltd. would like to inform the public that its office will be closed during the Chinese New Year holidays from 27th January 2022 and will resume business on 8th February 2022. We Apologize for Any Inconvenience Caused.ادامه مطلب -
Low frequency, high expectation ｜ trough of long wave: experimental radio bands lowfer, medfer and hifer
We most often use radio waves, whose frequency ranges from 3kHz to 3000ghz. In order of frequency from low to high, 3kHz to 30kHz are very low frequency, and VLF is the abbreviation of very low frequency. Then, as shown in the figure, it goes to the right and so on. The frequency is highe...ادامه مطلب -
The Future of UHF
The old saying “all changes are inseparable from their religion” applies to many things. Of course, it also applies to the problem of congestion in the electromagnetic spectrum. Just as the volume of gas continues to expand, new users will soon occupy new open areas of the rad...ادامه مطلب -
Mysterious CW signal received by USB at 16976 kHz off the coast of Brazil
I found this 2012 listening report on the Quebec amateur club website. It involves CW transmission by the Brazilian Navy at the same frequency of 16976 kHz. https://craq.club/files/documents/Archives/numeriques.pdf Is it just a coincidence that our mysterious CW station was reported by Br...ادامه مطلب -
In 1951, 220 MHz transceiver was used for civil defense
In May 1951, radio news designed the 220 MHz transceiver for civil defense purposes. This band is selected because it is authorized to be used by the holder of the new technician level operating license. Considering the operating levels of many new amateur radio enthusiasts, it is believe...ادامه مطلب -
How much bandwidth do we have to spend on amateur radio?
Did you spend some time thinking about the available bandwidth of various amateur bands? As an amateur licence holder, you can access six different amateur radio frequency bands: 80m, 40m, 15m, 10m, 2M and 70cm. If the bandwidth of each of these bands is added together, a total of 26.65mh...ادامه مطلب -
Entering the world of micro UHF Transmitter, 433MHz low power consumption is as small as button
The size of the transmitter designed by tomtechtod is almost as small as the 337 button battery that supplies it. The board of the mini PCB covers a large number of patch components, most of which are packaged in 0201. Even so, the transmitter is a simple design with two transistor audio levels ...ادامه مطلب -
Chinese New Year Closing Notice
Shengda Communications Co., Ltd. would like to inform the public that its office will be closed during the Chinese New Year holidays from 5th February 2021 and will resume business on 20th February 2021. We Apologize for Any Inconvenience Caused.ادامه مطلب -
144mhz cross equatorial propagation of 6102 km, FT8 or SSB mode can be used
144mhz open 6000km cross equatorial propagation (TEP) between Buenos Aires and the Dominican Republic Through cross equatorial propagation (TEP), the highly ionized region appears on either side of the geomagnetic equator in the F-layer of the ionosphere. This mode is so interesting because it a...ادامه مطلب -
Conflict with the military band, New Zealand ham regret unable to use the 60 meter section
Sorry! New Zealand amateurs cannot use the 60 meter band From October 24, New Zealand’s amateur radio enthusiasts will no longer be able to use the 60 meters. Radio amateurs in New Zealand use the band on a temporary basis, allowing ham in the region to use two frequencies, 5353.0 kHz and 5...ادامه مطلب -
TE connectivity launches new antennas for 5g, Nb IOT and lte-m
Shanghai, China – September 24, 2020 – te connectivity (TE), a global leader in innovative connectivity solutions for high-speed computing and network applications, announced the launch of new antennas for 5g, Nb IOT and lte-m to meet the requirements of cellular IOT devices for diffe...ادامه مطلب