This week, the ratings of three communications equipment stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Radware’s (RDWR) rating falls this week to an F (“strong sell”), down from last week’s D (“sell”). Radware develops, manufactures and markets application delivery and network security solutions that provide end-to-end availability, performance and security of mission critical networked applications. For Portfolio Grader’s specific subcategory of Earnings Growth, RDWR also gets an F. The trailing PE Ratio for the stock is 40.70. For more information, get Portfolio Grader’s complete analysis of RDWR stock.

This week, EchoStar Corporation Class A (SATS) falls to a D (“sell”), worse than last week’s grade of C (“hold”). EchoStar engages in the design, development, and distribution of digital set-top boxes and related products. The stock gets F’s in Earnings Growth, Earnings Momentum and Margin Growth. Shares of the stock have been trading at an exceptionally rapid pace, up threefold from the week prior. The stock has a trailing PE Ratio of 76.20. To get an in-depth look at SATS, get Portfolio Grader’s complete analysis of SATS stock.

Dragonwave Inc.’s (DRWI) rating weakens this week, dropping to a D versus last week’s C. DragonWave is a producer of high-capacity packet microwave solutions which support networking and other data transmission needs. The stock gets F’s in Equity and Cash Flow. For more information, get Portfolio Grader’s complete analysis of DRWI stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.