FCC + FCC = FCC?

2001-06-19 Thread John Cronin
Hi Group This is a question regardinga plug in PC card that has been stated as FCC compliant which is inserted in a PC that is also stated to be FCC compliant and theemissions are found to actually exceed the FCC limits. What is the responsibility of the manufacturer who is intending to place

Re: You won't believe this ... Well, maybe you will.

2001-06-19 Thread Rich Nute
Hi Doug: done, the entire safety approval reduced to a simple cfm rating fan for a chip both on the secondary side of the power supply. The issue for me is: What is the safety requirement that requires cfm (I presume a minimum cfm)? Reading between the lines... The fan

Products Electrical Ratings De-rated for Eurpoean Branch Circuits

2001-06-19 Thread Lesmeister, Glenn
Does anyone know if it is common practice or otherwise required to de-rate products in Europe to 80% (or some other %) of the rating of the branch circuit as is done in the US? Some product standards (such as 61000-3-2) apply to products rated up to 16A, so it would appear that products can be

You won't believe this ... Well, maybe you will.

2001-06-19 Thread Doug McKean
Dear all, In bringing a product through safety and having many issues, it might surprise you that after all was said and done, the entire safety approval reduced to a simple cfm rating fan for a chip both on the secondary side of the power supply. For some obvious reasons of which I hope

RE: braided vs served shields

2001-06-19 Thread CE-test - Ing. Gert Gremmen - ce-marking and more...
This might not directly answer your question, but may put some light on why these questions are difficult to answer in general. For all cables , the transfer impedance is equal to the Ohmic resistance of the shield at low frequencies. At higher frequencies the braiding effect causes due to the

RE: ISO TR 10605 test setup (ESD)

2001-06-19 Thread Mike Hopkins
Just one more comment: You never want a separate ground to a GRP that is different from other grounds in the building and more importantly, in the test area. There is a real risk of the GRP being at a different potential than other grounds, even if it is connected to a ground rod. Others have

Re: ISO TR 10605 test setup (ESD)

2001-06-19 Thread John Woodgate
83d652574e7af740873674f9fc12dbaa675...@utexh1w2.gnnettest.com, Chris Maxwell chris.maxw...@nettest.com inimitably wrote: The GRP's connection to Earth ground serves two purposes. It is a low frequency ground connection to ensure that, over time, the GRP's DC potential won't change with respect

Re: Clock dithering

2001-06-19 Thread John Woodgate
tkrepdavsml7e...@jmwa.demon.co.uk, John Woodgate j...@jmwa.demon.co.uk inimitably wrote: 4.3.2.7.2.20010618143751.00b3d...@box.tin.it, Paolo Roncone paolo...@tin.it inimitably wrote: As for interference to broadband receivers (like TV equipment) I remember a Lexmark study published a few years

May, 2001 EMC/Telco/Product Safety Update Now Available

2001-06-19 Thread Glen Dash
The Curtis-Straus Update is for May, 2001 is now available at: http://www.conformity-update.com The headlines are: THE EU, RTTE AND TRANSITION RULES. UPDATE ON THE US/EU MEDICAL DEVICE MRA. EC STANDS PAT ON FLAME RETARDANTS IN PLASTIC. BUSH TAKES CONTROL AT THE FCC. FCC TO AUDIT 25% OF TCB

RE: ISO TR 10605 test setup (ESD)

2001-06-19 Thread Chris Maxwell
Hi from one Chris to another, I'm going to address your ground rod concerns (Question 3). In our lab here, we have a new building with new wiring and a reliable third wire Earth ground, so I simply tie my Ground Reference Plane (GRP) to the third wire of one of the AC outlets in the room. I

ISO TR 10605 test setup (ESD)

2001-06-19 Thread Chris Chileshe
Hi group For those of you unfamiliar with ISO TR 10605, it is the ESD test standard for automotive electronics (8kV contact, 25kV air). I am trying to perform quick ESD tests on a product which has bottom entry proprietary cable. Picture if you an upside-down bottle of coke with push buttons

Re: braided vs served shields

2001-06-19 Thread John Woodgate
of8e69fc62.4b791cdf-on87256a6f.0070d...@us.datex-ohmeda.com, brent.dew...@us.datex-ohmeda.com inimitably wrote: Does anyone have any references or data on the comparative transfer impedance between served (spiral) and braided cable shielding at the same coverage level? It's heavily

Re: Clock dithering

2001-06-19 Thread John Woodgate
200106182001.qaa14...@interlock2.lexmark.com, rogle...@lexmark.com inimitably wrote: According to our extensive tests in conjunction with Philips Consumer Electronics, digital TV (both COFDM and ATSC) is actually less susceptible to interference from spread spectrum clocks (ssc) than current

Re: Clock dithering

2001-06-19 Thread John Woodgate
4.3.2.7.2.20010618143751.00b3d...@box.tin.it, Paolo Roncone paolo...@tin.it inimitably wrote: As for interference to broadband receivers (like TV equipment) I remember a Lexmark study published a few years ago that showed no increased interference from modulated clocks vs unmodulated clocks