Re: [PSES] Spread-Spectrum Clock Question

Probably explains why my wifi link is slower than advertised!!!  It is the error correction time... From: Ed Price To: emc-p...@ieee.org Sent: Friday, February 10, 2012 2:29 AM Subject: RE: [PSES] Spread-Spectrum Clock Question And we’ve been arguing about

Re: [PSES] Spread-Spectrum Clock Question

And we've been arguing about it ever since. The use of a QP detector and the 120 kHz defined RBW makes sense if you are trying to test to demonstrate minimum harm to a communications channel using AM modulation. Thus, if you do something to your clock that results in an indicated signal reducti

Re: [PSES] Spread-Spectrum Clock Question

The common spreading freq at the time meant that the interference passed thru the sensitive band at a frequency higher than our human visual and auditory perceptions, (It could be detected by comparing side by side, two systems, one with and one without) but for those of us that opinionated that

Re: [PSES] Spread-Spectrum Clock Question

Why is a spread-spectrum clock cheating? If the measurement BW is an accurate portrayal of the victims protected by the levied requirement, and if the QP detector is an accurate assessment of the nuisance value of the interfering signal modulation, then why is spreading the spectrum over a range o

Re: [PSES] Spread-Spectrum Clock Question

yeah! what John says. He now owns the consulting business started by Don Bush, and worked with all those guys long ago.| ps. I don't recall ever meeting John.  But I did work with the guys listed on the patent, when Lexmark was IBM. I recall the big surprise for me with this SSCG was we (Boca) th

Re: [PSES] Spread-Spectrum Clock Question

Neven,  you are right on with observations.  Except for your expectation. SSC works only with QP measurements.  Peak does not show any reduction using the 'normal' measuring techniques.| The modulating frequency I'm familiar with has been 50 kHz.| ps.  If implemented using small steps, or somethin

Re: [PSES] Melting BNC connectors

Hi John and the group, There were no markings of any kind on the devices. I bought several from a surplus house here in Silicon Valley so the source is unknown. Easy problem to test for though, buy one first, heat it up, results obvious. Doug On 2/9/12 5:52 AM, John Woodgate wrote: In messag

Re: [PSES] Spread-Spectrum Clock Question

Neven, I've worked with the EMC Engineers at Lexmark who invented the spread-spectrum clock generator (SSCG), since before they started its development. I used SSCG in a number of products that I designed at Lexmark. Below is my understanding of how SSCG works, based on numerous discussions with

Re: [PSES] RoHS

Gary, I share your pain. Another possibility is to offer to pay the company for the testing. That keeps the liability with them, gets you your data, and all for the price you would pay to do it yourself. Good luck, Marko From: "McInturff, Gary" To: 'Marko R

Re: [PSES] Spread-Spectrum Clock Question

There likely isn¹t much change with a peak detector, unless the frequency changes rapidly enough that it is in the pass-band of the receiver for less than 10 us (100 kHz RBW). If you use a QP detector, you will see a big difference. Ken Javor Phone: (256) 650-5261 From: Ken Wyatt Date: Thu,

Re: [PSES] Spread-Spectrum Clock Question

Neven, Your suspicion regarding the modulating frequency is on the right track. Normally, the mod freq is set just above the audio range. There's something very wrong if the specs only allow 3 to 100 Hz. Is that a misprint perhaps? You should be able to see the "spread" harmonics easily at 120

[PSES] Spread-Spectrum Clock Question

Hello, I wonder if anyone can help with a question I have on spread spectrum clock (SSC). I am trying to validate the effectiveness of a SSC chip to reduce emission. I measure with the peak detector. With the SSC enabled (up to 2.5% down-spread) I expect the level measured with a spect

Re: [PSES] RoHS - an EU view

Ron, I'm referring to industrial monitoring and control instruments mentioned in Article 4 paragraph 3 where it would seem doesn't have to comply until 2017. This category is covered by the directive but seems to have a delayed start date. The Other Brian From: emc-p...@ieee.org [mailto:emc-p

Re: [PSES] RoHS - an EU view

Hi Brian, With the new RoHS directive's Annex I, I would find it difficult to ascertain any equipment (EEE) getting an exemption (please note item #11): ANNEX I Categories of EEE covered by this Directive 1. Large household appliances. 2. Small household appliances. 3. IT and telecommunicat

Re: [PSES] RoHS

+1 Fully agree with Chris' statement below and with Brian Kunde's earlier message on "spot check" only. Supplier management in the RoHS domain is difficult but getting easier as more and more vendors get the message that it is not optional. ...Marko From: "J

Re: [PSES] RoHS

Get used to recurring testing. Think AQL. Have you looked at RoHS re-castigated? Brian -Original Message- From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of Kunde, Brian Sent: Thursday, February 09, 2012 6:36 AM To: 'EMC-PSTC@LISTSERV.IEEE.ORG' Subject: RE: RoHS Even if you t

Re: [PSES] RoHS - an EU view

If you have a product who's category falls into an exemption for a few years after the 2013 date, do you still have to show the RoHS directive on your DOC starting 2013, but somehow state it is compliant via an exemption, or just don't mention it until it is required? What is the proper procedur

Re: [PSES] RoHS - an EU view

One of the more interesting new Articles in RoHS II is Article 12 "Identification of economic operators Member States shall ensure that economic operators, on request, identify the following to the market surveillance authorities, for 10 years following the placing on the market of the EEE:

Re: [PSES] RoHS - an EU view

To all, In addition and especially to those that are not yet aware, please note that the current RoHS Directive (2002/95/EC) is now in a state of transition to the recast RoHS Directive (2011/65/EU), which wil

Re: [PSES] RoHS - an EU view

In message , dated Thu, 9 Feb 2012, iun...@servomex.com writes: Given that the adhesive is unlikely to contain lead, mercury, cadmium, hexavalent chromium, Any of those except perhaps cadmium, could be in mould and fungus inhibitor. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and

Re: [PSES] RoHS - an EU view

Group, Given that the adhesive is unlikely to contain lead, mercury, cadmium, hexavalent chromium, the question is: Does it contain either Polybrominated biphenyls (PBB), or Polybrominated diphenyl ethers (PBDE) at concentrations greater than 0.1% by weight of the homogeneous material? I understan

Re: [PSES] RoHS

If the mfr will not divulge the make up of the adhesive then switch to one who will. Any adhesive vendor placing their product into the EU either directly or indirectly should be cognizant with the requirements of REACH and almost certainly RoHS. Chris From: Kunde, Brian [mailto:brian

Re: [PSES] RoHS

Even if you tested the adhesive, since you do not have manufacturing control and the manufacturer is unable or unwilling to declare their adhesive RoHS compliant, you will not know if the adhesive will remain RoHS compliant. The manufacturer could change their adhesive without your knowledge. Yo

Re: [PSES] Melting BNC connectors

In message , dated Thu, 9 Feb 2012, N.Shani writes: Doug, you could do all of us a great service if you mentioned what & how the connector was marked, or where it was sourced. We all take short cuts every so often, so a Buyer Beware with a bit more details will be appreciated. I don't see

Re: [PSES] Melting BNC connectors

The better quality bnc connectors are usually nickel-plated brass. If you scrape a small area the brass color will show under bright light. Also, many of the cheaper connectors use dielectric material that will soften during soldering. Scott B. Lacey - -

Re: [PSES] Melting BNC connectors

Doug, you could do all of us a great service if you mentioned what & how the connector was marked, or where it was sourced. We all take short cuts every so often, so a Buyer Beware with a bit more details will be appreciated. Cheers, N. Shani Ottawa, ON On Thu, Feb 9, 2012 at 00:31, Doug Smith w

Re: [PSES] Melting BNC connectors

In message <07D4FF89DF924FC286DB1C551A1EA11E@LENVOR61iJOHN>, dated Thu, 9 Feb 2012, John Cotman writes: RoHS compliant pewter? Yes: lead used to be included in lower-grade material but has been eliminated from European pewter. From Wikipedia: QUOTE Pewter is a malleable metal alloy, tradit

Re: [PSES] Melting BNC connectors

RoHS compliant pewter? -Original Message- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: 09 February 2012 06:36 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Melting BNC connectors In message <4f335a4b.4000...@emcesd.com>, dated Wed, 8 Feb 2012, Doug Smith writes: >Who