Path: ...!local-4.nntp.ord.giganews.com!Xl.tags.giganews.com!local-2.nntp.ord.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail NNTP-Posting-Date: Wed, 29 May 2024 20:42:13 +0000 From: john larkin Newsgroups: sci.electronics.design Subject: Re: Distorted Sine Wave Date: Wed, 29 May 2024 13:42:13 -0700 Message-ID: References: User-Agent: ForteAgent/8.00.32.1272 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 26 X-Trace: sv3-QnsPA0IVP50vQ6TfQRPdgonwc9PLNYbTtrU1RhqdKZ22sedJNqpE6fC9lmvrZHk551eVqR09ngFZuHQ!lOH/o+TGp0BntdP6VJ0Vuxn8ejzWGYT8c/6YRLrQVMMJWN1jRm+3Mur+yzpC/IR/agVUvGFte/Ym!LKre+g== X-Complaints-To: www.supernews.com/docs/abuse.html X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 2031 On Wed, 29 May 2024 21:43:54 +0200, Arie de Muijnck wrote: >On 2024-05-29 19:07, Cursitor Doom wrote: >> Gentlemen, >> >> Whilst fault-finding on my HP 8566B spectrum analyzer, I've found the >> 10Mhz reference oscillator is generating an 'unsatisfactory waveform' >> which may be causing the device to be unable to lock it's main PLL. >> I've come across this waveshape before, but mostly with oscillators I was >> building and in the process of trying to iron out the wrinkles of and >> certainly NOT a critical reference oscillator from a respected >> manufacturer. Can anyone tell what's most likely going on here? >> >> https://disk.yandex.com/i/z6fYbeVfPRK7aA > > >Looks like reflections in the cable. Try the 50 Ohm termination. > >Arie If the drive is a sine wave, a cable can't generate that 2nd harmonic. Our boxes output a 10 MHz square wave. Our clock inputs have a 10 MHz bandpass filter, so they accept most anything.