RadioShack ( RSH) received a double whammy upgrade, sending shares of the electronics retailer soaring toward a double-digit increase in morning trading.The company was upgraded to outperform by both FBR Capital Markets and RBC Capital Markets on Friday, as it works to improve its wireless business. On Thursday, RadioShack struck a deal with T-Mobile to offer its wireless services and products in its stores. The company already carries Sprint ( S) and AT&T ( T) services. The only major service it is now lacking is Verizon ( VZ). Rival Best Buy ( BBY) has also been working to ramp up its mobile offerings. One of the main goals of new CEO Brian Dunn is to grow the company's cell-phone division, called Best Buy Mobile. Shares of RadioShack had jumped by 9.5% to $15.95 in late-morning trading.