APT photometry of the eccentric eclipsing binaries DI Her, AS Cam,
and V380 Cygni continued through 1996. Emphasis focused on obtaining
photometry of the eclipses to determine accurate timings as part of an
ongoing apsidal motion study. Guinan and astronomy student J. Marshall
have carried out a new apsidal motion study yielding a revised rate of
yr
yr. This
apsidal motion rate is close to that found earlier by Guinan, Marshall
& Maloney (IBVS 4101). Analysis of the residuals shows no evidence of
systematic or periodic variations to a level of about 
day.
No evidence of changes in the inclination of the orbit was found in the
constancy of the eclipse depths over time. From this data, there is no
support for the suggestion of a perturbing third star in this system.