Cathy,
Before desoldering the thermistor board, check all other places the 8B
voltage line appears carefully for solder splashes (U8, C103, C175, RFC16,
Q19 drain, U6 pin 8, etc - check the schematic for the questionable places).
Sometimes it is possible to examine the solder side of the thermistor board
more closely by removing the control board and the front panel.
Should you have to remove the thermistor board, plan on soldering on new
longer leads before re-inserting it - I find it much easier to replace the
leads with new ones rather than trying to struggle with putting the short
ones back into the 8 holes.
73,
Don W3FPR
> -----Original Message-----
>
> I have just completed (I think) Phase II construction of my K2, and I am
> getting ready to power up and calibrate.
>
> Unfortunately, I failed a resistance check. Page 59 of the manual says
> that the resistance from U6 pin 8 to ground should be >100 ohms. I get
> about 37 ohms.
>
> At first I thought this might be a bad thermistor, but looking at the
> schematic, even a direct short across the thermistor should not be able
> to lower the resistance that much. I have carefully examined the entire
> thermistor board area for shorted traces or contacts with neighboring
> components, but I can't seem to spot any. Are there other places/issues
> that could easily lead to the low resistance? (I have double-checked
> that the right resistors values are in the right place on the thermistor
> board.)
>
> I don't want to desolder the thermistor board unless I ABSOLUTELY
> have to...
>
> Thanks,
>
> Cathy
> N5WVR
>
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