This article is part of our Rising Star Portfolios series.

I've mentioned L-3 Communications (NYSE: LLL) many times in passing, but this time, I'm going to put my money where my mouth is. I'm buying $1,000 worth of shares for my Rising Star Portfolio.

My rationale for this purchase is simple: This is a great business trading at a great price.

Great business
L-3 is the premier defense electronics company, with products and services that run the gamut from secure data links and smartphones to unmanned aerial vehicles, training simulators, and aircraft modernization facilities. Many of its products occupy niche markets with little competition. This strong moat, and the critical solutions the company provides, give L-3 a heavily fortified position in the defense marketplace.

L-3 should also be insulated from the defense budget pressures emanating from Capitol Hill. Unlike defense behemoths Boeing (NYSE: BA) or Lockheed Martin (NYSE: LMT), L-3's products aren't platform-dependent, meaning they can be used on whatever aircraft platforms survive the possible defense cuts. If platforms get cut back, retrofits become more popular, and L-3 is in the sweet spot of that process with infrastructure (its Integrated Systems business) and products.

If the downside of government spending is potential cuts, the upside is insulation from the broader economy. More than 80% of L-3's revenue comes from the government, making the company essentially immune to economic pressures.

Great price
Usually, you'd have to pay up for this sort of business -- but defense spending fears have made it fairly inexpensive. L-3 expects to earn more than $8 per share this year, yet it trades for less than $80. On a free cash flow basis, L-3 should generate $1 billion in free cash flow, a hefty output on its $9.1 billion market cap. With earnings and free cash flow yielding 10%, this solid company is a wonderful buy.

I don't see much risk with this purchase, which is why I'm doing it. The company should grow faster than the defense budget, which won't drop as precipitously as media reports suggest. L-3's products are also very much in demand for their quality and value-creating properties -- something I like to see in any company, let alone a defense contractor.

This article is part of our Rising Star Portfolios series, where we give some of our most promising stock analysts cold, hard cash to manage on the Fool's behalf. We'd like you to track our performance and benefit from these real-money, real-time free stock picks. See all of our Rising Star analysts (and their portfolios).