Fluke 77IV and 179 differences with teardown photos

[retiredcaps]

I am only posting this information because there is already confusion about the 17x series battery life in this thread below.

https://www.eevblog.com/forum/repair/multimeter-repair-time-again!-fluke-177-reads-8-ohms/

I'm not OCD about this stuff, but I'm just trying to clear things up.

I tried to explain this in an earlier post, but perhaps I didn't explain it well enough.  So I will attempt again, but with snapshots from the datasheets and manuals throughout the years.

The 200hours.png is a datasheet showing alkaline 200 hours typical. 

The 300hours-1.png shows the 170 calibration manual dated April 2003 and 300hours-2.png shows alkaline 300 hours typical from the same manual.

The 400hours-1.png shows the current 170 manual straight from Fluke's website dated October 2008 and 400hours-2.png shows alkaline 400 hours typical.

As I mentioned, the Fluke 170 series has gone through radical pcb changes since its introduction.  For example, the proprietary Fluke asic ICs have been replaced with TI MSP430.  The MSP430 uses less power than the Fluke asic. 

As such, with each successive changes to the pcb, the battery life, as stated in the various revisions of the manual, have been revised upwards.  First, 200, 300 and finally 400 hours.  This implies that current consumption is halved since the initial introduction of the 170 series.

[Robomeds]

Since we are posting pictures, here is the PCB of my 177...

[therealjoephchrzempiec]

Hello I' new to the forum and please forgive me if I'm not asking this correctly. I have a fluke 179 coming in a few days but I was wondering if there is a way to be able to do a wireless interface. I do work with arduino and other wireless and blue tooth modules. But sense this is my first time modding a Fluke meter i have no clue.



Joseph

[EEVblog]

Revising old topic because it shows up on on a google search  and I just uploaded 77 IV PCB photos:

https://www.flickr.com/photos/eevblog/albums/72177720295682225

Fluke 77 IV Multimeter PCB by Dave Jones, on Flickr

[hunter_sk]

Thanks a lot for Fluke 77 pics, Dave!
I have Fluke 179 which is quite similar. It helps to track down layers of tracks, because on mine the top layer is not that transparent.

I have an issue with Fluke 179 precision. Ohms range shows about 30M when should be OL, and around 30 ohms when closed and decreasing to ~1 ohm for about a minute. (probes are fine)
VDC shows about 250mV on open loop when should be 0. Internal resistance is about 11M (sounds fine to me) and sending 1mA to probes when measuring resistance.
VDC on 9V battery shows difference from other DM about 0.2V.

I've measured reference voltage on pins 10,11 on IC and it's 2.5V. MOVs shows high resistivity (OL on my Voltcraft MT-52). Also measured some testpoints to discover abnormality. Most of them was 0.8V, one 4V sharp, TDI/TCLK shows about 0.05V  , P2.1/TB0 was negative

I'm not an electrician, just enthusiast, so just investigating from every sources I can get.
If someone can lead me to what I can check or when I can find that leak, I would be grateful.

[krefior]

Pretty sure the SL10327 Fluke Asic is bad.

[AVGresponding]

Thanks a lot for Fluke 77 pics, Dave!
I have Fluke 179 which is quite similar. It helps to track down layers of tracks, because on mine the top layer is not that transparent.

I have an issue with Fluke 179 precision. Ohms range shows about 30M when should be OL, and around 30 ohms when closed and decreasing to ~1 ohm for about a minute. (probes are fine)
VDC shows about 250mV on open loop when should be 0. Internal resistance is about 11M (sounds fine to me) and sending 1mA to probes when measuring resistance.
VDC on 9V battery shows difference from other DM about 0.2V.

I've measured reference voltage on pins 10,11 on IC and it's 2.5V. MOVs shows high resistivity (OL on my Voltcraft MT-52). Also measured some testpoints to discover abnormality. Most of them was 0.8V, one 4V sharp, TDI/TCLK shows about 0.05V  , P2.1/TB0 was negative

I'm not an electrician, just enthusiast, so just investigating from every sources I can get.
If someone can lead me to what I can check or when I can find that leak, I would be grateful.

Please tell me you didn't have the 179 measure its own battery. This is usually a bad idea...