The sign says "Honk If You Hate Dallas," and if you didn't know you were on the corner of Loudoun and Gerrard streets in this Shenandoah Valley town, you'd think it was a rush hour traffic jam on K Street in Washington--air horns, blare horns, horns that play Dixie. The noise is constant and deafening, all of it for the Washington Redskins.

People here in Apple Country have contracted the Fever, all right. One hundred miles from RFK Stadium, this town is ready for today's Redskins-Dallas Cowboys standoff. A local radio station is playing "Hail to the Redskins" every hour, and a disc jockey at another has put up a crate of Shenandoah apples against a case of Lone Star Beer in a bet with a D.J. in Dallas.

Two Cowboys are being tortured in effigy, and the newspaper is set to run a Redskins feature story and color picture on the front page today. A local bar owner has promised half-price brew if the Skins win and he's looking for a way to make the beer flow Redskins burgundy from the taps.

The county planner has cautioned his heavily expectant wife not to deliver during the game, and during a recent meeting of the Frederick County Republican committee, one of the speakers promised a victory in November, just as sure as "the Redskins are going to beat Dallas."

Of course, some of this spirit is due to the residence here of two former Redskins--Bill Brundige, the general manager at Lamar Sloan Ford, and Ron McDole, owner of Ron McDole, Inc., a company that makes library furniture. But the roots of devotion run deeper, to the late 1930s, when George Preston Marshall brought the team to Washington from Boston. He vowed to make the Redskins the "team of the South."

These were the days before expansion teams brought football to Atlanta, New Orleans and Miami, days when the Redskins' marching band played "Dixie" in the middle of the team's fight song, "Hail to the Redskins," and the Redskins radio network carried Sunday games throughout the South. Tickets to home games were sold as far south as South Carolina, and the railroad made special runs into Washington for games. The Redskins also were the last NFL team to have black players.

Sidney A. Carroll, who served as business manager and then general manager of the Redskins between 1937 and 1947, sits at Redskins home games near a doctor who teaches medicine at the University of West Virginia in Morgantown--a three-hour drive from Washington--and has been coming to games for more than 20 years. The doctor, Carroll says, "keeps talking about transferring to Johns Hopkins so he won't have to drive so far to see the Redskins."

Redskins games still are carried on at least eight southern TV stations--including one in Florence, S.C., four in North Carolina and three in Virginia (Norfolk, Richmond and Roanoke). And the Redskins radio network has 45 stations in Virginia, 42 in North Carolina, four in West Virginia and one in Miami--with occasional games being carried in Dallas, said Jim Gallant, program director for WMAL radio.

Today, in rural Virginia towns like this one, the team that former Virginia governor Linwood Holton once called the Virginia Redskins is still the home team, make no mistake about that.

Ask Bill Pugh how Winchester regards the Redskins and he'll walk outside his Midas Muffler dealership and show you his burgundy Cadillac. He has a war bonnet--bought for $6, including tom-toms, at Nichols Department store--perched on the hood. In the windshield, he has a drawing of a pair of cowboy boots wearing a cowboy hat. The slogan: "This is a cowboy with the s--- kicked out of him."

Next to the Cadillac stands a Chevy pickup truck adorned with a life-size dummy of a Cowboy with a spear through its chest. The dummy is compliments of Midas employe Mike Effler, who is wearing a "Hog Hat," a black baseball cap with pink ears and a pink nose above the brim.

Effler also contributed a poster of motorcyle-riding Miss Piggy, labeled "Hog Heaven," and a poem that hangs on the pickup reads: "There is no way through RFK/ Joe and the 'Gang' are here to stay/ Dallas can look and better pray/ But Washington going all the way."

Across the street from the Midas shop, Max Short runs the Mel-Max Room, a lone fort of Cowboy resistance. The scene yesterday was good-natured contention, the boasts and counter-boasts being apportioned, like the mashed potatoes, in healthy helpings.

"Y'all know now that if the Redskins win, Max is gonna be waxing my car for a year," said Pugh.

"All I'm gonna be doing for the next year is smiling at all your Redskins foolishness," responded Short.

Sitting at the counter with Pugh, Winchester Star sportswriter Mac Rutherford shook his head. "Damn," he said. "Haven't seen this much excitement around here in years."

Rutherford said that recently one of the town's many season ticket holders accosted Star publisher Tom Byrd--son of retired Virginia senator Harry F. Byrd--and argued that the Star's headlines weren't pro-Redskins enough. "Byrd told him that the Star was the most pro-Redskins paper in the state," Rutherford said.

At local country radio station WUSQ, morning D.J. Dusty Rhoads has been playing songs such as "Mama Don't Let Your Babies Grow Up To Be Cowboys," "Cowboys and Clowns" and "Cowboys Don't Shoot Straight."

Rhoads also has been airing fanciful interviews between a character he calls Howard Wholesale and Cowboys named "Tom Laundry," "Danny Blight" and "Phony Corset," who Rhoads said would "like to become a Dallas Cowboy cheerleader when he retires."

The fever is hot, all right. The other night, when Star sports editor Ken Morrison went into Enrico's Pizza Shop, another customer declared: "This game is the biggest event in the free world!" No one disagreed.