On Sunday, October 29, 2017 at 5:03:43 AM UTC-7, wrote:

Freeze spray is still with us. It is useful for tracing intermittents and components that fail when warmed up. But, be very careful with it. Cold spray hitting an overheated part or board can cause fractures - which can cause trace failure.

But, it has other uses. A little freeze spray onto one of dozens of DC/DC converters
identified the source of an annoying crosstalk situation, and we gained about 6 dB of
extra signal/noise, once I'd isolated the ripple source. You can also (roughly) identify hot
components, by observing how fast the frost dissipates.