Walthams 77 model numbers started @ 992501 & finished 3189000. At no.1342701 they started to make them "quicktime" & this continued right up until the last "77" was made ( according to my Ehrhardt Walthambook )Can any member explain what qt means and are there any advantages to it.

The term of "quicktime" Derek would be referring to "Frequency" (Hertz or Hz) or "Beats Per Hour" (Bph), also terms such as "Slow Train" & "Fast Train" were also used, these are not to be confused with "Coarse" and "Fine" trains. The earlier Model 77 Waltham's were 16,200 BPH or 2.25 Hz, when the change was made they then were 18,000 BPH or 2.5 Hz.

The reason behind "increased Frequency/Bph" ("equals more stored energy", so less prone to disturbances) is for improved accuracy (the faster or higher frequency, then the less escapement error) across and during all types of conditions the watch might encounter.

Thanks Bila. When you look @ a running watch & the balance is just a blur there`s a good chance the watch is in fine condition & probably accurate. ( just my opinion )
Was the length of the pallet used to vary the bph ?

Helps to have them in hand though Derek as you probably are already aware, as photos tend to be miss leading. Pallet length has no bearing on the frequency rates.