esd protection at 900MHz cordless phone
I'm looking some advices from the ESD protecting on antenna matching network. I have put ESD protection device (TVS,contains ~50pF cap) in parallel with existing matching circuitry, problem is the power output dropped significantly -9dB after adding the TVS. I truely believe it was because the inner cap value of the TVS had changed the impedance matching. During the ESD test (12KV, contact dischage to the the antenna), the front end SAW filter revelaed increasing leakage & unsatble. The experience shows that the cap must be as low as possible <3pF of inner TVS, but this is impossible to the device makers. Your idea or comment in providing the solution is very appreciated. Scott Chiang Application Engineering AVX/Kyocera Taiwan
RE: Please Help! Need EMI Shield for LCD Panel!
Brian, You may contact specialized manufacturer in shielded, transparent windows at: IVC Displays Tel: (011) 44 1332 864-900 28-30 Derby RoadFax: (011) 44 1332 865-409 Melbourne, Derbyshire DE73 1FE United Kingdom Mirko Matejic The Foxboro Company -- From: Brian Kunde To: emc-p...@ieee.org Subject: Please Help! Need EMI Shield for LCD Panel! List-Post: emc-pstc@listserv.ieee.org Date: Monday, July 29, 1996 9:21PM Now that I need one I can't find one. I am in need of a transparent shield that will go over a 9 inch diag. LCD Panel. Years ago I had vendors knocking down my doors with these cheep shields that where made from a fine conductive screen material with a small frame and a drain (ground) wire. Does anyone know a company that still makes these things? How about the raw material (I can make them myself)? Thanks in advance, Brian Kunde bku...@qtm.net LECO Corp.
Re: China Japan Regulatory Issues
DENTORI is Japan's Material Safety Law which calls out mandatory requirements for consumer products. If a product falls under the scope of DENTORI, compliance is mandatory, and for some products, certification by MITI (Ministry of International Trade and Industry) is mandatory. ITE does not fit under the scope of DENTORI. In Japan there are no mandatory requirements for ITE equipment. However, there are requirements for external computer power supplies. They must meet DENTORI and requirements and require MITI Certification. As to the rationale, your guess is as good as mine. There are some voluntary schemes in Japan that may help you meet market requirements. They are: VCCI: Japan's Voluntary Council for Control of Electromagnetic Interference by Data Processing Equipment and Electronic Office Equipment VCCI certification involves emissions testing only of equipment The requirements are similar to CISPR 22. S-Mark: This is a new voluntary scheme in Japan encompassing both safety and emissions requirements. If a product does not fall under the scope of DENTORI and a manufacturer wants some third-party certification for Japan, this may be the way to go. The certification bodies involved include JET and JQA . For further information on Japan, I would suggest you contact UL's International Compliance Services Department in Melville. They have a group of engineers who are experts in Japan's requirements. Contact Mr. Hiroshi Morimoto at 516 271 6200. Regarding China, there is a new Product Quality and the Import and Export Commodity Inspection Law for ITE. Under the new system, importers must have a product safety mark from CCIB (Chinese State Administration of Import and Export Commodity Inspection). The certification will involve type testing, evaluation of the quality system and factory follow-up. Products without certification will be prohibited from entering the country. This law will go into effect for ITE October 1996. I received this information from an ITI bulletin dated July 25, 1996. UL can probably assist you with this too. I hope the above helps. Regards, Kelly Colon Kelly Colon Regulatory Engineering Symbol Technologies Inc. Voice: 516 738 3480 Fax: 516 738 3318 e-mail: col...@symbol.com The opinions expressed above are my own!!!
Re: ask for mail list on EMC
So glad to see colleagues from China interested in EMC. Hope you'll bring us the latest EMC and safety reg in China today. You sent an empty message to the whole group. Should you want to subscribe the EMC-PSTC, send the email to majord...@mail.ieee.org with the following in the body, subscribe emc-pstc I maintain a web site with regulatory information probably in your interestes, the URL is http://uc.com/compliance_engineering Again, nice to see Chinese frm China. Your name sounds familiar. Best regards, Tom Bao On Tue, 30 Jul 1996, YANG Hai-Tao wrote:
Re: Field Retro Options into Noncompliant Machines
I find it useful to draw analogies with user friendly things like personal computers. Your three cases then become: >1) ADD AN OPTION WHICH ALLOWS MACHINE TO PERFORM FUNCTION >IT COULDN'T PREVIOUSLY DO. Add a sound card to an old 386 - the sound card must be CE marked and shown to comply with EMC requirements but it doesn't affect your old 386. >2) ADD AN OPTION THAT DUPLICATES AN EXISTING FUNCTION; Add a second sound card (or whatever) to your old 386 - again, the sound card must be CE marked but it doesn't affect the old PC. 3) ADD AN ADJACENT MACHINE THAT WORKS IN TANDEM WITH THIS MACHINE AND COMMUNICATES WITH IT; Add a printer connected via interface cable to the parallel port of your old 386 - again the printer must be CE marked, etc, but still your old PC remains the same. If this analogy is an accurate reflection of your situation, then none of your situations require looking at old installed equipment. You need to look at the add-ons. "Opinions expressed are my own and not necessarily those of my employer." James Cunningham Radio Frequency Investigation Ltd Ewhurst Park, Ramsdell Basingstoke Hampshire RG26 5RQ England Tel: (+44) 01256 851193, j...@rfi.co.uk
Please Help! Need EMI Shield for LCD Panel!
Now that I need one I can't find one. I am in need of a transparent shield that will go over a 9 inch diag. LCD Panel. Years ago I had vendors knocking down my doors with these cheep shields that where made from a fine conductive screen material with a small frame and a drain (ground) wire. Does anyone know a company that still makes these things? How about the raw material (I can make them myself)? Thanks in advance, Brian Kunde bku...@qtm.net LECO Corp.
