Sorry ...cannot help....but do you have the instructions in English ? I bought this model second-hand in Zagreb market and it does not switch on ! All that happens is a quick flash on the display saying BT 15 !
IDD CI24 ECONO MM Penta 1.20 Galaxy II
1.2Mtr Polar MTG yes it has been on the arc for 25 years and is now fixed on 13 East using two pairs of rusty molegrips. Unlike me they never groan but always perform.