Tandy Corp seems to have had a happy Christmas: the electronic retailer reports that December sales were up 23% at $568.1m, sales from US Radio Shack stores were up 21% at $526.3m, and sales from stores open a year ago were up 18%, all comparisons with December 1985; Tandy also says that it looks for a 19% increase in fiscal second quarter sales to around $1,190m; the figures are due later this month.