Updated IceTube Clock Design

After fin­ish­ing the IceTube clock ver­sion 1.31 build for myself, I was ready to work on the board design for some IceTube clocks as gifts. I could have used the exist­ing V 1.31 boards, but I want­ed to use an up to date design that incor­po­rat­ed all the hard­ware improve­ments over the past 10 years while still stay­ing with a thru-hole design.

IceTube clock Version 2.1 mount­ed in laser cut acrylic enclo­sure. March 2020
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Wien Bridge Oscillator Design

Wien Bridge Oscillator  HPV testing for THD
Wien Bridge Oscillator HPV test­ing for THD

I found myself in need of a very low-dis­tor­tion 1,000 Hz sine wave
gen­er­a­tor for an upcom­ing project.
A quick search on Ebay found sev­er­al used pieces of test equip­ment that met or exceed­ed my require­ments, but were priced at well over $1,000 USD.
I did also find some low-cost China sourced 1 kHz gen­er­a­tor boards, but they had a dis­tor­tion of 0.1% which was way above my 0.005% lim­it.
My cur­rent test gear includes a Keithley 2015 THD Multimeter with a low dis­tor­tion sine wave gen­er­a­tor, but it is only capa­ble of 0.03% THD at 1 kHz.
It was time to see if I could build some­thing for under $100 that would meet my needs.

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