Hi everyone, i have bought this Fluke 73 series 1 but it's not turning on, I can't find schematics for the series 1 i have found only series 2 and 3, and based on that i have tried the test points and i got wrong voltages, is there any way to fix it! it got some corrosion that i cleaned but no luck

 

I don't like the looks of this. Is it really broken off as it appears in the photo? Whatever that chunk is seems to be directly opposite the multi-pin chip on the other side of the board. Is it maybe a heat sink of sorts?

 

yup, it looks like it had date with Zeus...

Hi everyone, i have bought this Fluke 73 series 1 but it's not turning on, I can't find schematics for the series 1 i have found only series 2 and 3, and based on that i have tried the test points and i got wrong voltages, is there any way to fix it! it got some corrosion that i cleaned but no luck

and what exactly is that supposed to tell us? you measured what, where using what and got what result?
how does it behave when you power it on? any sign of life? anything on display?

 

yup, it looks like it had date with Zeus...



and what exactly is that supposed to tell us? you measured what, where using what and got what result?
how does it behave when you power it on? any sign of life? anything on display?

No sign of life at all, no display

 

in that case, chance of repairing it is gone...

 

Does it chirp on continuity. I had one who’s lcd didn’t work but the meter did..

 

I don't like the looks of this. Is it really broken off as it appears in the photo? Whatever that chunk is seems to be directly opposite the multi-pin chip on the other side of the board. Is it maybe a heat sink of sorts?
View attachment 373083

Just a cutout (maybe for thermal, solder or testing) under the battery.That's only a part of the chip on the other side. Looks normal.

I have my old 73 that still works (10A section was lost decades ago)





Negative battery test point.

Battery 8.84V
Switch on ACV, measured from the top going clockwise.


0
0
8.84
2.87, probe connect here causes display to change.
0
5.75
8.84
8.84
8.84
5.75
5.75
8.84

To the OP, check these voltages with a fresh battery. Report back here, I'll be glad to help if possible.

 

Good call from nsaspook on the test points — do those with a genuinely fresh 9V first, and measure the battery while the meter is switched on. A 9V that reads 9V open-circuit but sags below about 7.5–8V under load, or a corroded battery clip, will give exactly these 'wrong voltage everywhere' readings. Also try the continuity beeper: if it chirps, the main chip is alive and the fault is likely the LCD zebra strip / display contacts, not the power rail. Clean the rotary switch contacts with isopropyl alcohol too — on a meter this age a dirty range switch drops more voltage than you'd expect.

 

Just a cutout (maybe for thermal, solder or testing) under the battery.That's only a part of the chip on the other side. Looks normal

Ah, it's an innie, not an outie! I saw it as a broken rectangular object, not a hole.

 

Just a cutout (maybe for thermal, solder or testing) under the battery.That's only a part of the chip on the other side. Looks normal.
View attachment 373115
I have my old 73 that still works (10A section was lost decades ago)
View attachment 373112View attachment 373118


View attachment 373114
View attachment 373119
Negative battery test point.

Battery 8.84V
Switch on ACV, measured from the top going clockwise.
View attachment 373116View attachment 373117

0
0
8.84
2.87, probe connect here causes display to change.
0
5.75
8.84
8.84
8.84
5.75
5.75
8.84

To the OP, check these voltages with a fresh battery. Report back here, I'll be glad to help if possible.

Sorry for my late reply, and thank you for your efforts and help!

Here are the results:
6,43
7,60
9,36
7,6
7,6
8,51
9,36
9,36
9,36
8,51
8,51
9,36
Tp1 9.36 while it's turned on ACV
Tp3 8.07 while it's turned on ACV

 

I know it's a series I but the II service manual should be close for power/switch connections. Page 62
https://media.fluke.com/080bccab-5c8c-4480-8576-b10800bebaeb_original file.pdf

Give me some time to cross check a few things.