Radomes and Windload - Kirby's Musings

RADAR Types and Locations - Kirby's Musings

RADAR in the United States.

National defense and surveillance RADAR: https://en.wikipedia.org/wiki/Joint_Surveillance_System#Radar_stations
NOAA Weather RADAR: https://en.wikipedia.org/wiki/NEXRAD#Operational_locations
Terminal Doppler Weather RADAR, at airports: http://www.wispa.org/Resources/Industry-Resources/TDWR-Resources/TDWR-Locations-and-Frequencies
Wind Profilers use a UHF frequency in the 70cm amateur radio band, which is described to be unmodulated (zero bandwidth) and transmitted directly up to detect wind shear conditions: https://en.wikipedia.org/wiki/Wind_profiler NOAA coordinates frequencies under NTIA and may not disclose locations. A wind profiler at airport KHSV was announced some number of years ago but the frequency was not disclosed. 449 MHz has been published elsewhere.
https://www.esrl.noaa.gov/psd/technology/tars/ https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System#Technical_and_operational_data

FCC ULS provides information on the following types:

AR: Aviation Radiolocation [Aviation RADAR, on-aircraft]
LN: 902-928 MHz Location Narrowband (non-multilateration)
LS: Location and Monitoring Service (LMS), multilateration
LW: 902-928 MHz Location Wideband (grandfathered AVM)
MR: Marine Radiolocation Land [Ship RADAR]
RS: Land Mobile Radiolocation ["Police" and other low-power (5 W) mobile/temporarily fixed licensed RADAR, as well as high-power (220W TXPO but 225 kW ERP) TV weather RADAR]
WR: Microwave Radiolocation

Additionally, there are low-power unlicensed RADARs on 10 GHz (X-band) and Ku (13.45 GHz) as well as Ka bands (24.0-24.05 GHz).

Fasteners, Vibration, and Locknuts - Kirby's Musings

Compressor Smashing - Kirby's Musings


How to Mash the Compressor

VLC contains a built-in audio compressor. This can be taken advantage of for spoken word material and for movies, in the case where you need to reduce the dynamic range of the material due to a loud environment, or compress the peaks above a certain point to prevent excessive loudness.

Audio Effects -> Compressor
 - Check Enable
 - RMS / Peak: 0.0
 - Attack: 1.5 ms or as fast as it will go
 - Release: 2 ms or user option as to release time
 - Threshold: -24 dB
 - Ratio: maximum (20:1)
 - Knee: maximum (10:1)
 - Makeup gain: 24 dB

Note that adjusting threshold will put the compressor into action earlier and limit the output amplitude of the compressor; the makeup gain is directly related to this number to flatten out the overall amplitude of the compressor output.

Adjusting the attack and release introduces various effects and depending on time constant, can make aspects of the audio stream "pump". This is not a desired effect. Multiband dynamics processing in radio stations avoids pumping effects in the bass region if at all possible.

BIRDWATCHER - Kirby's Musings

Birdwatcher is a word which has mostly avoided the internet generation entirely. Birdwatcher is an automated telemetry system with two pilot inputs, an A button and and a B button, and the rest of the inputs were specific telemetry inputs on the aircraft. The A-12 had a Birdwatcher system, as well as the CIA version of the U-2. Both of these aircraft or similar variants (U-2S, SR-71) were transferred to the 9th SRW, 4080th, and other related divisions.

Birdwatcher also involved a time-division aspect to the received signal. A physical measuring apparatus is used to determine the source module of the telemetry burst from a strip-chart recorder.

For more information, look to the dead trees.



pdftops filter failed - Kirby's Musings

If you're reading this, you probably have a problem with Cups and pdftops failing. Install xpdf and some version of libpoppler. This is an unresolved dependency.

Terminal Gibberish - Kirby's Musings

When your terminal is liberally filled with terminal gibberish, there are a few solutions suggested on stackexchange:


I suggest this:

echo ^V^[c

Alternatively (noobish):

echo <CTRL-V><CTRL-[>c

The actual character being echoed is ^[ followed by the letter c, but to pass control-[. one must type CTRL-V before other CTRL- sequences. Clear as mud, eh?

Thermodynamics or Thermonuclear War - Kirby's Musings

Law I: You can't win, you can only lose.
Law II: The only way to win is not to play.

In thermodynamics and energy conversion systems, the rules of thermodynamics are immutable. The only variables to implementation are 1) cost of design, 2) labor cost of design implementation, and 3) materials cost of design implementation. These variables all support one equation to calculate a single value: return on investment (ROI), less maintenance cost.

In converting from AC to DC or DC to DC, the fewer the steps, the greater the efficiency. The more transistors act like switches and less like variable resistors, the higher the efficiency. The lower the loss in the transformer or inductor stages, the greater the efficiency. A 90% (0.9) efficient inverter connected in series with another 90% (0.9) efficient inverter results in an overall efficiency of (0.9 x 0.9 = 0.81) 81%. Thus it is most important to make sure that any conversation stage is as efficient as possible to eliminate losses which will invariably appear as heat. This is true of electrical distribution systems, backup power supplies, line-shaft power systems, and belt-powered systems as well.

In a belt-based transmission system, losses can be as high as 5% per stage. Similarly, gear-based transmission systems and hydraulic systems also suffer from losses due to realistic implementation concerns. Multiple stages, lubricants or lack thereof, and turbulence further lower overall efficiency. Thus, while it may be possible to store energy from a solar collector by raising a rail car full of concrete to twice it's height, much energy may be wasted in mechanical gear trains unless a mechanically large gear is used and a small pinion. Even then, one would need a considerable motor/generator to convert from electrical to mechanical.

AT&T Tower Resources - Kirby's Musings

Free Rigging Guides - Kirby's Musings