[Test-Equipment] Racal Dana 1992 time counter ,help needed

[marcelo]

Hi evrybody 

When I switch it on shows that message : "1992" and after that "8572 04.04"  I think it coluld be the software version o something like that Afetr that "000000000" is displayed and everything works fine 
But, time to time ,it reset itself and everything start again "1992" "8572 04.04" once and once again ,until finally after 20 min or so "000000000" is dispalyed and the counter is ready to use "continuosly "
A thermal problem ? Has a option "rubidium standard " (oven )
Any idea ? 
Thank you in advance 

Marcelo