Web-Based RF Calculators From Pasternack
Pasternack is known for their wide assortment of RF adapters, attenuators, connectors and cables and has been growing their product line with passive and active components, including 60 GHz microwave systems. The company recently launched a website with RF calculators and conversions.
The calculators I checked out were based on simple formulas that most RF engineers should be familiar with. Pasternack's presentation, however, makes them very easy to use.
One example is the Waveguide Calculator (Rectangular). The program allows selecting standard waveguide sizes, but doesn't include the huge waveguides used for high-power UHF. A “custom” option allows entering the broad wall width in inches, centimeters or millimeters. I put in 15 inches and results showed a cutoff frequency of 0.4 GHz and an operating range of 0.5-0.7 GHz.
The Free Space Path Loss Calculator should be helpful when testing microwave links.
Some of the applications may be too simple for broadcast facilities. The Antenna Downtilt Calculator should work well for very short links, but since it doesn't take Earth curvature or atmospheric refraction into account I wouldn't count on it for longer paths.
While many of these formulas and calculators can be found on-line at other sites, having this collection in one place is handy!
TWICE Offers More Solutions for Cord-Cutters
The September 8 issue of the Consumer Electronics Associations TWICE (This Week In Consumer Electronics) newsletter describes some more over-the-air DVR options in Cord-Cutters Awash in New Solutions by Greg Tarr. Tarr describes the solutions from TiVo, Channel Master, SimpleTV and others as well as Tablet TV, which started a beta launch in the San Francisco area in partnership with KOFY-TV, owned by Granite Broadcasting. Tarr writes, “The system, for which pricing wasn’t announced, is designed to put the ability to watch and record all subscription-free, live HD television anywhere directly onto tablets via an over-the-air signal transmitted to a small antenna.” He adds, “Tablet TV will look to provide those TV services that Aereo TV tried and ultimately failed to deliver.”
Tablet TV requires a “T-Pod,” which contains the ATSC tuner and connects via Wi-Fi to the tablet. For more on Tablet TV, see my article Motive Television/Granite Broadcasting Plan Tablet TV Service Launch. The product was demonstrated at this year's NAB Show in the ATSC technology area.
