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AU2V, Sacrifice Rock DXpedition, 7th to 10th February 2025

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The Sacrifice Rock DXpedition team has announced the dates on their website. It is from 7th to 10th February 2025. Frequency plan is also online, with operations from 80m to 10m, including WARC bands. CW, FT8 and SSB modes have been planned. Operation on FT8 will be on Fox/Hound mode. Split operations are planned to handle pile ups better. They will be listening for stations from United States of America specifically on 7160 kHz. There is only a small time window of propagation from this region to the United States. Time window to the US corresponds to the grey line propagation . That is early morning and evening or dawn and dusk. All of us in this region are quite excited about the Sacrifice Rock DXpedition. We are looking forward to this DXpedition coming up very near us. VU3WEW took this video clip while on a reconnaissance trip to Sacrifice Rock last week. He has taken this video clip from a boat, travelling quite near to the tiny island. Single glance will tell you the advent...
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Why is Yaesu FT-60R Dual Band Handheld 5W VHF/UHF Radio Trending?

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 When I checked for Google Trends for Amateur Radio, I found that Yaesu FT-60R Dual Band Handheld 5W VHF/UHF Amateur Radio Transceiver as the top trending topic with breakout results. But when I searched after some time, the top one was IC 7300 and it kept on changing frequently. May be because the total number of searches are not high compared to other search terms on Google. Checked Amazon.com about the availability and found that it is available, but will not ship to my region. I had noted that the interest on Google was mainly from United States of America. I noted Weather Alert as a special feature on Yaesu FT-60R. That may be the reason for it trending in the US. Other features seem to be similar to other dual band handheld radios, with 1000 memory channels and coverage for both VHF and UHF amateur radio bands as well as additional wide band receiver coverage, mentioned as even up to 999.99 MHz. That is just below 1 GHz! That could be another reason why it is popular in the U...
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What is USB-C PD and can it be used in Ham Radio?

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 As most of us are aware, USB is a data transfer protocol which has been revised from the original Universal Serial Bus to the latest USB4, with data transfer speeds up to 80 Gbit/s. Type C is the designation of the connector which you are familiar in mobile phone chargers. Type A plug and socket are the ones you connect with your laptop and type B the one for your printer. A cable to the printer from the laptop will have type A plug at one end and type B plug at the other end. My FT-710 radio uses a similar cable for CAT control or Computer Assisted Transceiver control as well. PD stands for power delivery and the current USB cables are capable of power delivery with rapid charging of devices including mobile phones with varying levels of voltage and current. Original USB devices could deliver only 5 V while the latest ones can deliver even up to 48 Volts and 240W. The white cable is a conventional USB type A to type C cable. The black one is thicker USB-C PD or power delivery cab...
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What is Radiation-hardened-by-design (RHBD) in satellite technology?

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 Radiation-hardened-by-design (RHBD) is a methodology that uses circuit techniques to make microcircuits more resilient to radiation as required at outer space in case of amateur radio satellites. In case of amateur radio satellites, it is more relevant for medium earth orbit and geostationary satellites located at higher altitude. You may remember that GreenCube or IO-117 failed after a good period of operation, possibly due to radiation induced damage. Ionizing radiation in outer space include particle radiation and high energy electromagnetic radiation. On the terrestrial aspect, RHBD devices are needed around nuclear reactors, particle accelerators and during nuclear accidents. Radiation hardening of semiconductor electronic components require some design and manufacturing variations that reduce susceptibility to radiation damage. As the demand will be low and extensive development efforts are needed, production of radiation-hardened chips lag behind the most recent development...
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The All New zBitx 5 watts QRP All Band, All Mode Radio is Here!

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 VU2ESE has announced the launch of zBitx on the BITX group. It is available for purchase at http://www.hfsignals.com/ and delivery will start in February 2025. According to VU2ESE, it is a low cost 5 Watt, 80m to 10m QRP radio with a 480x320 touch screen that allows you to run CW, FT8 and other digital modes without needing even a phone that the original zBitx needed. As previously posted, zBitx is based on a Raspberry Pi Zero 2 W, which gives it the prefix 'z'. The physical size of zBitx is just 6 inches by 3.5 inches, 1.5 inches thick, weighing just 250gm, and includes a battery case that can hold two 18650 lithium polymer batteries. One has to get batteries from elsewhere. External DC supply can also be used with a maximum of 9V. zBitx seems to be quite 'pocket friendly' both in the literal sense and cost wise! An HDMI monitor, keyboard and mouse can be plugged in, to use like a QRP base station. zBitx runs the same software as sBitx radios. zBitx will ship with...
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What is an LCR meter?

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 LCR meter is an instrument used to measure inductance (L), capacitance (C) and resistance (R) as the name indicates. They can measure the impedance to a sinusoidal waveform of definite frequency and convert the measured value to capacitance or inductance. Higher end machines can measure true inductance or capacitance, equivalent series resistance of capacitors and Q factor of inductors. As actual capacitors and inductors are not ideal devices with only either capacitive or inductive components, they have a resistance in series which is defined as the equivalent series resistance. It is often taken as a resistance to alternating current, measured at a specified frequency which could be the self-resonant frequency or 100 kHz for switched mode power supply ( SMPS ) components and 120 Hz for linear power supply components. Q factor or quality factor is the ratio of a resonator's center frequency to its bandwidth when subject to an oscillating driving force. It is a dimensionless param...
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Building 80m Inverted V Antenna for Restricted Space: VU2XTO Design

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Caution: VU2XTO has informed that high power with a linear amplifier should not be delivered to this loaded coil dipole as it can result in heating of coils.  I can hardly squeeze in a 40m inverted V at my home. Still I wanted to try out 80m as some of my VU friends have started trying it out. I was told by an online DX friend that 80m is a very busy band in EU with DX even up to Middle East at night. I was active on 80m in 1980s with a horizontal dipole antenna tied on top of coconut trees at my parents' home using a homebrew 3 x 807 AM/CW radio. VU2XTO design published in the Madras Amateur Radio Society Newsletter, Volume 26, Issue 2, July-September 2018 has the details of an 80m antenna for restricted spaces. What we need is a couple of 118 microhenry loading coils and about 14 m of insulated copper wire. For the 118 microhenry coils, VU2XTO has suggested a 15cm UPVC former of 1.5 inch diameter and 18 SWG enamelled copper wire wound closely for a span of 11cm. It is basically a...
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