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Tame Your Coax Choke

 Owen Duffy simulated a Common Mode Choke (CMC) using RG316 coax and  2643251002 toroid ferrite core . See his post here . I found the double-shielded RG316 coax I was using had a life of its own with regards to routing. My understanding is that windings close together boast capacitance, which can negatively affect the choking performance, especially at the high frequency end of the HF spectrum. I designed and 3D printed a part which solves this.
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Photos of the MC-750 Antenna

 The MC-750 is a ground-plane antenna, designed for easy setup and takedown - perfect for field ops like POTA. The MC-750 is well made. Others can review this antenna better than myself. Instead of a review, enjoy these photos of the MC-750 antenna.
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Quirks of the Fuchs B25 Antenna Tuning Unit

 As illustrated in this photo from the manual, the Fuchs B25 transceiver was designed to be operated manpack portable with a whip antenna. To couple this whip antenna to the transceiver, an Antenna Tuning Unit (ATU) is employed. ATUs normally enable the use of a wider range of antennas, however the B25's ATU was designed for a specific purpose and is not so adaptable.
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A Low-Loss EFHW Transformer

 The End Fed Half Wave (EFHW) is a convenient antenna. The core component is a wide band impedance matching transformer. As with all antenna systems, efficiency is a key metric. Special selection of the transformer core and winding style can allow for an acceptably efficient EFHW antenna.
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Bad Bananas

Banana connectors are quite ubiquitous in the electronics world, and rightly so: they are versatile, inexpensive, and easy to terminate. However early on into my electronics engineering journey I discovered there are some bad  apples  bananas to lookout for.
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A Banana Adapter for the B25 ATU

 The Fuchs B25 manpack transceiver has an Antenna Tuning Unit (ATU) designed to match a short whip antenna, or feed a wire antenna. While I haven't measured the impedance tuning range of the ATU, it seems to be able to tune most loads I have connected to the transceiver. The ATU's utility is quite useful for my portable ham radio operations so I'd like to keep it in service.
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5 Reasons to use Zero Ohm Resistors

Some newcomers are shocked when they learn about a zero ohm (0R) resistor. These curiosities do actually come in handy for practical electronics design. Here are five good examples.   Bridging over tracks In some electronics design cost is a major constraint to balance, along with circuit function. To reduce costs, reduced layer counts may be employed, e.g. two layer or even single layer PCBs. Take the single layer scenario. The layout of the components may be such that the resulting tracking is impossible. A 0R resistor 'cheats' the single layer constraint by bridging one track over another.   Component values to be determined Sometimes component values aren't known until the circuit has been built. A good example of this is an antenna matching network. It can be difficult to simulate the entire product (electronics and mechanicals) to gauge the feedpoint impedance of the antenna. Instead, a generic matching network is designed in, using 0R resistors as placeholders. For s
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