Re: TCXO - 0.5PPM

Posted by ab2tc on Dec 29, 2010; 8:53pm
URL: http://elecraft.85.s1.nabble.com/TCXO-0-5PPM-tp5872529p5875517.html

Hello again,

While I don't disagree with other people's suggestions that visual aids would be of assistance I am still a little bit at a loss (no pun intended) why your hearing loss should be a serious obstacle to detecting the zero beat on the side tone. Do you have any problem hearing your chosen side tone at all? In CW mode turn the AF volume down to 0 and press "Spot" to hear the side tone. If you can't hear the side tone, you need to adjust its frequency and/or amplitude until you can hear it clearly (hold "Pitch" to adjust frequency, hold "Mon" to adjust volume). Now is the time to turn the AF gain back up until you can hear stuff roughly equally as loud as the side tone. The flutter or warble in the side tone generally can't be heard easily unless you are within 20Hz or so of the desired frequency, so maybe that's your problem. I can send you a recording of what WWV sounds like with say a 10, 3 and nominally 0 error if you think it might help. Tried this just now and the fast flutter at 20Hz frequency error is clearly audible.

AB2TC - Knut

radioshoppe wrote

Knut,

Thank you for your suggestion.  As mentioned in my email about the best I can do with Method 2 is about +/20 hz.  I've tried it numerous times.  When adjusting the frequency I hear a dead spot 25-40+ hz wide that has no womp-womp-womp.  I take half of the width and set the frequency there.  Spend 20+ years around aircraft and very noisy missile sources in the Air Force 30-50 years ago.  I had rather buy more radios/accessories than pay $6-10,000 for a set of hearing aides.

Happy new year,  73

Jim, W0EM
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