Data Technology Model 40 digital multimeter 4½ digit 1973 teardown

absolutly lovely and super accurate unit from 1973, it uses neon filled high voltage beckman and sperry displays, ADC is Dual slope clocked 138kHz read out 4.5Hz update ,
display is +/-20000 counts,
No manual, No schematic available for free online, please help with that, scan and share.
AC range 5Hz to 30KHz, Resistance range max 10 Meg. not 100Meg, must be explained in the manual we dont have.
Uses 8.4 Watts from mains before i changed the caps, now with new caps it uses 7.5Watts :-) so i guess i found a little leaky cap, I also added a few Air circulation holes arround the power supply area and back of case.
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#voltmeter
#teardown
#vintage
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I use auto generated subs, i am sorry there are a few spelling errors,
maybe one day they can do it better..
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