9V/Grnd Continuity ?

Started by captntasty, August 22, 2006, 11:03:11 AM

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captntasty

I'm embarrassed to even ask this question but my brain is fried due to sleep deprivation.  I'm working on the tonepad ver. of the FSH1 and got it working (sort of) - distorted, just isn't right (that's another topic).  In the process of debugging I resoldered a few things, had to jump a few traces as they had breaks and no continuity.  It started working a little better, then I did something, unable to recall what and started having the problem of the 1044 overheating.  Now to the question - when I test from ground to where 9V comes in and anywhere along the +9V rail there is continuity (very slight resistance) - I'm going under the assumption that there shouldn't be, right?  I've checked and scraped between traces many times over with no luck.  Anyhow, my brain is fried and I'm confused - perhaps I shouldn't have tackled such a complex project with a colicky newborn to handle...   
It is no measure of health to be well adjusted to a profoundly sick society. - Jiddu Krishnamurti

petemoore

 Sleep and eat...
  Then...
    wrap yourself around the fact that continuity between +/- in a power supply is a search mission with very little navigation...like searching the ocean for a 'teeny dot person' [especially when surveying a large board].
  Bias voltages and audio probing are useless when no power can be applied...it's just a matter of finding it visually...
 
Convention creates following, following creates convention.

captntasty

Strangely enough I took a 1/2 hr break, played drums with my daughter, came back and voila - no overheating... ???  I'll take your advice Pete and give it a rest before jumping in to debug the rest - it will take more effort than I have to expend just to get all the voltage measurements.  Would it be best to get all the voltages before diving in to the audio probe?

Thnx, you always seem to be the one responding to my dumb questions... 
It is no measure of health to be well adjusted to a profoundly sick society. - Jiddu Krishnamurti

petemoore

  Here ya go...your 'dumb question' [pardon the term] has made me think of a great debugging tool, which will:
  GREATLY IMPROVE THE EFFECIENCY OF ANY DEBUGGING
  Moreso on 'monster' circuits like FSH.
  Use a Recorder.
  Clip the black lead to Gnd. on DMM set to voltage range.
  Hit REC button.
  Say...Q1 C, 1.5v / Q1B 4.7v
  Go quickly through the entire circuit recording the voltage measurements.
  Hit playback and start typing or notating...on the voltage chart you've prepared?, possibly just using the printer?
  This should greatly decrease the time it takes by eliminating the need to 'triple task' tasks which require re-orienting mental focus...hitting the right pin with the DMM probe, reading the meter, dropping everything to write down that reading...
  Also you will get more accurate voltage measurements more easily...I can't count the times I couldn't count where I was and have to re-start or re-check because the pen/paper method requires 'bookmarking' places in two separate task areas.
  If the phone rings, hit STOP, rewind is the bookmark.
Convention creates following, following creates convention.