The grades of four Diversified Telecommunication Services stocks are better this week, according to the Portfolio Grader database. Every one of these stocks has an “A” (“strong buy”) or “B” overall (“buy”) rating.

IDT Corp. (NYSE:IDT) is bumping up its rating from a C (“hold”) to a B (“buy”) this week. IDT provides retail and wholesale telecommunications services and products, including pre-paid and rechargeable calling cards and wholesale carrier services. In Portfolio Grader’s specific subcategories of Earnings Momentum, Cash Flow, and Margin Growth, IDT also gets A’s. The stock price has risen 5.2% over the past month, better than the 3.4% increase the S&P 500 has seen over the same period of time. The stock’s trailing PE Ratio is 4.80. For more information, get Portfolio Grader’s complete analysis of IDT stock.

Primus Telecommunications (NYSE:PTGI) earns a B this week, jumping up from last week’s grade of C. Primus Telecommunications Group offers international and domestic voice, voice-over-Internet protocol, Internet, wireless, data and hosting services to business and residential retail customers and other carriers located in North America, Australia, and Europe. Wall Street seems to agree with the upgrade and has propelled the stock up 8.4% over the past month. For more information, get Portfolio Grader’s complete analysis of PTGI stock.

ORBCOMM Inc. (NASDAQ:ORBC) improves from a C to a B rating this week. ORBCOMM operates low earth orbit satellites and ground infrastructure that enable customers to track, monitor, control, and communicate with fixed and mobile assets located anywhere in the world. Investors have pushed the stock price up 8.4% over the past month. For more information, get Portfolio Grader’s complete analysis of ORBC stock.

This week, inContact’s (NASDAQ:SAAS) ratings are up from a C last week to a B. inContact provides cloud-based contact center software services and network connectivity in the United States. Investors seem to agree with the upgraded status of the stock, and have pushed the stock up 28.3% over the past month. For more information, get Portfolio Grader’s complete analysis of SAAS 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.