Data Precision 5740 counter

This is an ageing piece of equipment but a goody. Has anybody got a manual for this count that contains the full circuit diagram please. All the downloads I have found have had circuit description and block diagrams but no service info or circuit diagram, can anybody please help without it this is just a piece of junk.

That is a vintage piece of equipment (circa 1970's) and I happened to have access to the original service manual!

At a time, Data Precision equipment were highly sought after. They were widely used & calibrated for maintenance due to it's build quality & precision design.
The Company was absorbed and they have mainly been purged from our system but many of the "yellowed paper" original service information still exist in the calibration dept.

If you are going to attempt, due to the age, I'd say Electrolytics and switch contacts should be first in order..
4oo DPI scan of three main sections listed below.
Best to download each separate page.
You can view/magnify it in any PDF viewer;

https://drive.google.com/file/d/1fmc-0c1VsetIstAgUyzYCVLXsof57HTR/view?usp=sharing
https://drive.google.com/file/d/1mhZA_ZCKUjQmu4DHZzPPr7bZhFmqQwJy/view?usp=sharing
https://drive.google.com/file/d/1_ep_JiiPCobtn99ofPvqq-0Sjki1ImjO/view?usp=sharing

Hi vtech, That is absolutely fabulous it is exactly what I need. At this age your suggestions make a lot of sense, at present it seems to be free running and an input appears to have no effect. I can't thank yo enough for the information and if you have anything else you feel may be useful it would be really appreciated. I knew somebody out there had to have the info I needed

Hi vtech would you have access to the printed circuit board layout, it would make life a lot easier as about 6 of the ic,s are not identified and I am not great at chasing printed circuit tracks?
Thanks

Here you go;
https://drive.google.com/file/d/1HcS3IImkp_nkHfXvizWYlEWhrwJwJ63p/view?usp=sharing

Great, Many thanks