LOSS OF ELECTRICAL PWR MANDATES THE DIVERSION TO ANOTHER ARPT BY A CFI AND STUDENT IN A TRAINING FLT 25 MI NE OF HFD; CT.

Narrative

I WAS CONDUCTING AN INST TRAINING FLT. WHILE IFR ENRTE TO BRIDGEPORT; CT; FROM NASHUA; NH; 6000 FT MSL; VMC; ON TOP OF AN OVCST LAYER WE WERE 25 NM NE OF THE HFD VOR ON THE 030 DEG RADIAL; LEVEL. MY STUDENT AND I NOTICED ABNORMAL BACKGROUND NOISE OVER THE RADIOS AND SPEAKER. WE CHKED THE RADIO SETTINGS; CIRCUIT BREAKERS AND AMMETER. THE AMMETER WAS INDICATING A DISCHARGE CONDITION. THERE WAS NO LOW VOLTAGE INDICATION; AND IT SHOULD BE NOTED THAT THE LOW VOLTAGE LIGHT CHKED OUT NORMAL ON PREFLT. WE IMMEDIATELY REDUCED THE ELECTRICAL LOAD AND THEN COMPLETED THE EMER CHKLIST FOR ELECTRICAL FAILURE. WHILE THE STUDENT WAS COMPLETING THE CHKLIST I TRIED TO CONTACT ZBW TO NOTIFY THEM OF MY STATUS BUT WAS UNSUCCESSFUL. I THEN SQUAWKED 7600 BUT SOON AFTER REALIZED WE WERE ALSO WITHOUT ANY NAV EQUIP. UNABLE TO FOLLOW MY RTE CLRNC; I DECIDED IT WAS BEST TO FIND VFR CONDITIONS. WE DSNDED TO OUR MEA OF 3000 FT MSL AND WERE VMC BELOW THE OVCST. ON A HEADING OF 210 DEGS WE HAD THE CITY OF HARTFORD OFF OUR 9 O'CLOCK POS; AND CIRCLED W OF THE CITY TO VERIFY OUR POS WITH A VFR SECTIONAL. MY STUDENT CALLED FSS ON CELL PHONE TO NOTIFY SOMEONE AND SEE IF WE COULD GET VECTORS. MEANWHILE I SEARCHED FOR A ROTATING BEACON AND SPOTTED ONE. BRADLEY TWR HELPED VERIFY OUR POS JUST S OF BDL THROUGH THE FSS VIA OUR CELL PHONE. WE WERE INSTRUCTED VIA THE PHONE TO REMAIN VFR AND ENTER A L BASE FOR RWY 33 AND AT THE SAME TIME CLRED TO LAND. ON FINAL WE RECEIVED A GREEN LIGHT SIGNAL AND LANDED UNEVENTFULLY. I THINK THIS SIT COULD HAVE BEEN EASIER TO HANDLE IF I HAD REMEMBERED TO BRING MY HAND HELD NAV/COM.