Collaborate Disseminate
It might not count as “DC to daylight,” but an electromechanical attenuator that covers up to 70 GHz is pretty close, and getting a guided tour of its insides is …read more Continue reading A Look Inside a 70-GHz Electromechanical Attenuator
There are those among us who might bristle at something from the early 1980s qualifying for “Retrotechtacular” coverage, but it’s been more than 40 years since the California Department of …read more Continue reading Retrotechtacular: Crash Testing Truck Attenuators, for Science
It’s not often that a single photo can tell you pretty much everything you need to know about a project, but the spectrum analyzer screenshot nearby is the perfect summary …read more Continue reading Wien Bridge Oscillator Drives Distortion Into the Floor
The HP 11947A is something of a footnote in the back catalogue of Hewlett Packard test equipment. An attenuator and limiter with a bandwidth in the megahertz rather than the gigahertz. It’s possible that few laboratories have much use for one in 2019, but it does have one useful property: …read more
Continue reading A Modern Take On A Piece Of Old Test Equipment
In the RF world, attenuators are a useful test and measurement tool. Variable units that can apply different levels of attenuation in discrete steps are even better. [DuWayne] made a 63 dB step attenuator by putting two smaller units in series, with an Arduino Nano in control of them. With …read more
Continue reading A DIY Step Attenuator, By Gluing Together Two Smaller Ones
[Kerry Wong] comes across the coolest hardware, and always manages to do something interesting with it. His widget du jour is an old demo board for a digital RF attenuator chip, which can pad a signal in discrete steps according to the settings of some DIP switches. [Kerry]’s goal: forget the finger switch-flipping and bring the attenuator under Arduino control.
As usual with his videos, [Kerry] gives us a great rundown on the theory behind the hardware he’s working with. The chip in question is an interesting beast, an HMC624LP4E from Hittite, a company that was rolled into Analog Devices …read more
Continue reading Digital Attenuator Goes from Manual to Arduino Control
If you catch a grizzled old radio amateur propping up the bar in the small hours, you will probably receive the gravelly-voiced Wisdom of the Ancients on impedance matching, antenna tuners, and LC networks. Impedance at RF, you will learn, is a Dark Art, for which you need a lifetime of experience to master. And presumably a taste for bourbon and branch water, to preserve the noir aesthetic.
It’s not strictly true, of course, but it is the case that impedance matching at RF with an LC network can be something of a pain. You will calculate and simulate, but …read more
Continue reading Pi Network Attenuators: Impedance Matching For The Strong Of Signal