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Dear All,
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<div class="">On 31.03.2020, at 06:59, Patrick via users <<a href="mailto:users@ntpsec.org" class="">users@ntpsec.org</a>> wrote</div>
<div class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">For
less than 50 ms drift over 3 months, it looks like an OCXO will</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
<span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">likely
hit the max drift wall:</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">
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<div class="">I have now running a voltage controlled and heated XO since several years but more than 20 month without power outage. I have a drift of about 7 ms/month </div>
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<div class="">But I see two issues: </div>
<div class="">* if the power fails the drift is huge after it is switched on again. It takes 6 months up to three quarter of a year until the frequency is as stable as before. </div>
<div class="">* as it is voltage controlled I can pull the frequency to the correct value. but after days it starts again to drift away. I do this game now since some years but I don’t see an end. </div>
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<div class="">But I think 80 ms/year isn’t so bad but to get this value is hard. </div>
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<div class="">Kind regards </div>
<div class="">Hans </div>
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<div class="">— </div>
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