[sdiy] Help with oscillator

[Scott Gravenhorst]

madhun2001 at yahoo.com wrote:
>
>Hi all,
>
>I have been humbled by the most simple of circuits: an 
>oscillator. Its one of those crystal oscillators used everywhere. 
>The circuit is here: 
>
>http://circuitabbey.com/files/EqualTog_sch.pdf
>
>Its the circuit in the upper left corner: U6. This same circuit 
>worked fine on the first board. I have since swapped the crystal 
>and 18p caps from the working board to the bad one, but no joy. 
>The output at pin 6 has about 4 KHz on it, and pin 1 has no 
>signal at all, just a DC bias. I tried cleaning the board with 
>flux remover. Now even the 4KHz signal is gone. 
>
>Any ideas? Thanks in advance.

Wow, really simple...  Assuming the IC is the exact correct type - a
new one?  Measure the supply for correct voltage steady DC?  Resistors
OK?  The PC board has no breaks?  (I've seen _hairline_ breaks in a
commercial PCB that I fixed with a little piece of wire and some
solder.  Reflow all solder connections?  Can't thing of much else to
check or replace...  When you find it, I want to know what it was (c:

What are those SJ things that look sorta like a neon lamp symbol
without the circle around it?

-- ScottG
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-- Scott Gravenhorst
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