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CRYSTAL TUNING PART II
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Re: CRYSTAL TUNING PART II

by Barry914 on Thu Jun 19, 2014 10:11 am

Sent you an email

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Re: CRYSTAL TUNING PART II

by jarchie on Thu Jun 19, 2014 5:10 pm

Sorry! I never received the message. Would you mind forwarding your email directly to my personal address?

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Re: CRYSTAL TUNING PART II

by Russell 27 on Sat Jun 28, 2014 1:13 pm

EXTERNAL SMD Oscillator.PNG
EXTERNAL SMD Oscillator.PNG (400.96 KiB) Viewed 473 times


To anyone interested; This SMD external Oscillator combines the best of both worlds, minimal VOLTAGE variation, while buffered. It's more reliable than the internal ATMEGA crystal inverter gate. Not much bigger than the Maxim time chip. Built it on a Schmart SOIC Board, Gate was a Rohm BU4SU69G2 single inverter. Soldered in over the original crystal mounting. Buffered Pin on the upper right will accept test lead. Based on the original Tuned Pierce Oscillator post, The capacitors are 3- 25 Pico Farad, set around 25 Pf. This board and circuit had virtually no inherent capacitance.
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Re: CRYSTAL TUNING PART II

by jarchie on Sat Jun 28, 2014 4:40 pm

nice!

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Re: CRYSTAL TUNING PART II

by Russell 27 on Sat Jul 12, 2014 1:12 pm

Oscillator top.PNG
Oscillator top.PNG (581.39 KiB) Viewed 448 times

Oscillator side.PNG
Oscillator side.PNG (649.67 KiB) Viewed 448 times

SMD Oscillator mounted... Measurement ZIP contains scope readings, circuit and notes.

MEASUREMENTS.zip
(47.13 KiB) Downloaded 53 times
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