A leaked internal memo suggests that RadioShack is preparing to launch a no-contract wireless service on September 5. The offering would be powered by super regional carrier Cricket Wireless, a subsidiary of Leap Wireless that provides service to over 7 million customers in the US.

Cricket already offers a similar no-contract plan but RadioShack will reportedly be upping the ante by including an 8GB microSD memory card with phones equipped to use Cricket’s Muve Music rental service. As CNET described during a review of the service, it’s essentially a clever way to roll a music subscription service into a monthly plan that includes talk, text and data.

All we have to go on at this point is the memo shown above which unfortunately doesn’t outline which phones will be available under the RadioShack No Contract Wireless program. Furthermore, monthly pricing isn’t mentioned but if we had to guess, it’ll likely be priced in line with other pre-paid wireless services – or around $50 per month at most.

Gotta Be Mobile doesn’t believe RadioShack will have access to the recently-launched iPhone for Cricket as they say it’s usually pretty hard for mobile virtual network operators (MVNOs) to get Apple’s handset on their network. That said, they expect RadioShack to mostly offer Android-based handsets and lower-end feature phones.

As it stands, September 5 is gearing up to be pretty busy as Motorola is hosting their Razr HD event and Nokia is putting on their Windows Phone 8 event the same day. Given those two events, RadioShack’s launch could fall behind in press coverage.