A C172 PLT MADE SOME INCORRECT ASSUMPTIONS AND VIOLATED THE CAMP DAVID TFR.

Narrative

I CONDUCTED A FLT FROM MARTINSBURG; WV (MRB); TO FREDERICK; MD (FDK); TO HAGERSTOWN; MD (HGR); TO MARTINSBURG; WV (MRB). THIS WAS MY FIRST FLT INTO THE AREA AS I HAD JUST RETURNED TO FLYING UPON RETIRING AND HAD BEEN RENEWING MY FLYING SKILLS. THE PLANNING FOR THE FLT BEGAN THE PREVIOUS EVENING WHEN I CHARTED THE RTE; UPGRADED THE SOFTWARE ON MY GPS AND PURCHASED THE COMMERCIAL CHART UPDATE TO THE DATABASE. I NOTICED THAT THE LEG FROM FDK TO HGR CAME WITHIN A COUPLE OF MI; BUT DID NOT ENTER R-4009 AROUND CAMP DAVID. I PLANNED TO STAY WELL W OF MY COURSE TO ENSURE NO ENTRY INTO R-4009. I CALLED ELKINS FSS FOR A BRIEFING AND WAS ADVISED THAT THE TEMPORARY TFR AROUND CAMP DAVID WAS IN EFFECT. I ASKED HIM IF IT WAS 10 NM. HE RESPONDED THAT YES IT WAS 10 NM. UNFORTUNATELY; I THOUGHT THAT THE TFR WAS A 10 NM DIAMETER AROUND CAMP DAVID; AND UNFORTUNATELY THE BRIEFER DID NOT SPECIFICALLY ADVISE ME THAT IT WAS A 10 NM RADIUS FROM CAMP DAVID. I WENT TO MY CHART AND MEASURED R-4009 TO ENSURE IT WAS 10 NM IN DIAMETER. SO R-4009 MUST BE THE OUTLINE FOR THE TFR. AS I FLEW THE LEG FROM MRB TO FDK; I MONITORED 121.5 AS I KNEW I WOULD BE FLYING WITHIN ABOUT 6 NM OF THE WASHINGTON ADIZ. AFTER A TOUCH-AND-GO AT FDK; I PICKED UP THE RTE TO HGR AND; AS PLANNED; I STAYED A FEW MI W OF MY COURSE TO AVOID THE TFR WHICH I BELIEVED TO BE REPRESENTED ON THE CHART AND MY GPS AS THE OUTLINE OF R-4009. AFTER A FEW MINS IN THE AIR; I HEARD POTOMAC APCH ON 121.5 ADVISING THE ACFT OVER I-70 AT 2300 FT; SQUAWKING 1200 THAT THE ACFT WAS ABOUT TO ENTER AN ADIZ. UNDERSTANDING THAT HE MUST BE CALLING ME AND BELIEVING I HAD SOMEHOW GOTTEN TOO FAR S INTO WASHINGTON ADIZ; I IMMEDIATELY TURNED N FOR A COUPLE OF MINS; BEFORE RESUMING A NORTHWESTERLY COURSE FOR HGR. HOWEVER; I MUST HAVE BEEN APCHING THE CAMP DAVID TFR AND NOT THE WASHINGTON ADIZ; SO MY TURN TO THE N ACTUALLY PUT ME INTO THE RESTR AIRSPACE. WHEN I CONTACTED HAGERSTOWN TWR; I WAS ADVISED THAT I WAS RIGHT ON THE EDGE OF A TFR AND TO TURN IMMEDIATELY W. I CHANGED COURSE TO THE W AND WAS THEN DIRECTED BACK TO HGR FOR LNDG. AS I LEFT HGR FOR MRB; THE TWR GAVE ME A PHONE NUMBER TO CALL WHEN I ARRIVED AT MRB. THE NUMBER WAS FOR POTOMAC TRACON AND THE CTLR TOLD ME THAT WHEN I HAD ABRUPTLY TURNED N I HAD GONE ABOUT 1 MI INTO THE CAMP DAVID TFR.