Uploaded June 2025 | Updated September 2026, 2 weeks ago

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We dive into the intimidating RF guts of an HP 8664A 3 GHz high-performance RF generator. And there is an extra level of difficulty - being from the 1990s, HP doesn't even give the schematics for it. That's going to make our life way more difficult.
Repair playlist: youtube.com/playlist?list=PL-_93BVApb590G-B-_pAp528IiPNnD7H3
PLL Frequency Synthesis is explained in this video: youtu.be/z-50pSc_wg8
RF Mixers are explained in this video: youtu.be/01GzduUaLOE

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"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeod

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