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Radio Wrangler · 15th Aug 2019, 5:59 am

Highly suspicious.

A look with an oscilloscope would show if it was 2v DC or a logic waveform with an average of 2v, switching between 0 and 5v. Though I suspect 2v DC is the most likely.

This node needs checking for dirty connectors, muck on boards, bad connections (IC sockets?) and if nothing found it would point to failed IC. The glass passivation of this era of chips created a corrosion problem on the metal layer of the die if moisture crept into the package.

David

15th Aug 2019, 5:59 am	#22
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,869	Re: Yaesu FT480R Highly suspicious. A look with an oscilloscope would show if it was 2v DC or a logic waveform with an average of 2v, switching between 0 and 5v. Though I suspect 2v DC is the most likely. This node needs checking for dirty connectors, muck on boards, bad connections (IC sockets?) and if nothing found it would point to failed IC. The glass passivation of this era of chips created a corrosion problem on the metal layer of the die if moisture crept into the package. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done