[time-nuts] Fluke monitor

Leigh L. Klotz, Jr WA5ZNU Leigh at WA5ZNU.org
Mon May 17 05:12:33 UTC 2010

You're right about the current.  I just checked it with my DMM and got 
45ma. My inline power meter must not be that it's not that accurate at 
the low end.

The display works; the backlight works; the processor must be doing 
something since it prints a variety of messages.  It's the RS232 that 
has flakey.  The hardest thing at this point is to unsolder the 16-pin 
header.  Bob suggests that a 12v regulator may have failed.

> In a message dated 12/05/2010 17:45:16 GMT Daylight Time, Leigh at WA5ZNU.org
> writes:
> The  monitor is a recent model and has the regulator. I left it on
> overnight,  in its original case and out in the open, hooked to a 13.5V
> supply. I had  it on a ammeter the whole time, and it never draws more
> than 0.02A.   The backlight is fine and the display works.
> --------------------------
> Something doesn't seem right with that current consumption.
> Mine's not in use at the moment, as my test area is still stripped down,
> but when it was I measured a consistent 47mA once the regulator had a high
> enough supply to ensure it was regulating, in my case I was using 12 volts
> but the current is determined by the regulator output voltage so shouldn't
> vary  much anyway.
> The display is what was fitted originally fitted to the iCruze module but
> the processor board has been changed so that Didier's Tbolt Monitor code can
> be  used.
> The processor module circuit is pretty basic so I wouldn't have  thought
> there was too much room for a design error.
> I'd be inclined to start by separating the processor board from  the
> display and then reconnect using a temporary link of flexible wiring so  as to be
> able to check if the processor circuitry is actually drawing  current, then
> I'd probably continue by looking for quality issues, bad  joints, solder
> bridges, etc.
> If that turned up nothing obvious then a more in depth examination of what
> the processor is doing would be my next step, in particular it would be
> interesting to know how it's handling the RS232 interfacing just in case it's
> a  comms issue.
> Given that Didier's code is freely available, and the processor board
> schematic is easily traced, it shouldn't be too difficult as a last resort just
> to build a replacement.
> regards
> Nigel
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list