PA28 PLT ENTERED DC ADIZ WITHOUT A CLRNC OR DISCRETE XPONDER CODE.

Narrative

I WAS OPERATING MY PRIVATELY OWNED ACFT FOR PLEASURE IN AND AROUND CALVERT COUNTY; MD. I WAS USING CURRENT VFR CHARTS AND VFR PILOTAGE TECHNIQUES TO REMAIN CLR OF THE WASHINGTON DC ADIZ. THE DCA DME WAS NOT USABLE DUE TO MY ALT AND OVER-THE-HORIZON LIMITATIONS. THROUGHOUT THE ENTIRE FLT; I HAD THE CALVERT MEMORIAL HOSPITAL; THE BENEDICT BRIDGE ACROSS THE PATUXENT RIVER; AND THE TOWN OF SCIENTIST CLIFFS IN SIGHT. WHILE I KNEW I WAS IN PROX TO THE ADIZ; AT NO TIME DID I BELIEVE I HAD INTRUDED INTO THE AIRSPACE. I HAD ATTEMPTED TO CONTACT PATUXENT APCH ON 120.05 AFTER TKOF AND WAS TOLD TO 'IDENT.' I COMPLIED AND AFTER A FEW ATTEMPTS; WAS UNABLE TO REACH THEM DUE TO SATURATION AND FINALLY; ALT LIMITATIONS. AT NO TIME DID I HEAR A CALL ON PATUXENT APCH OR THE VHF GUARD FREQ THAT THERE MAY BE AN INCURSION INTO THE ADIZ. UPON LNDG AT 2W6; I WAS TOLD BY THE FBO OWNER THAT I NEEDED TO CONTACT POTOMAC APCH AND THAT THERE WERE 2 ACFT ATC WANTED TO CONTACT REGARDING ADIZ AIRSPACE INTRUSIONS. I CONTACTED POTOMAC APCH VIA PHONE IMMEDIATELY. THE CTLR STATED THAT HE OBSERVED MY ACFT OPERATING INSIDE THE EDGE OF THE ADIZ BY AS MUCH AS 2 MI. RECOMMENDATION: DUE TO THE UNCERTAINTY OF VFR PILOTAGE TECHNIQUES AND DISTANCE MEASURING EQUIP; I STRONGLY RECOMMEND THAT ALL PLTS GIVE THE ADIZ AND ALL OTHER CTLED AIRSPACE A MUCH WIDER BERTH WHEN OPERATING VFR IN PROX TO SUCH AREAS. FURTHERMORE; I RECOMMEND THAT ALL PLTS VACATE THE AREA IF THEY ARE NOT UNDER POSITIVE RADAR CONTACT AND IN 2-WAY COMS WITH THE APPROPRIATE FACILITY WHEN OPERATING IN THIS ENVIRONMENT.