Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Bill Sloman Newsgroups: sci.electronics.design Subject: Re: RF Connector Type ID Date: Sun, 9 Jun 2024 23:15:44 +1000 Organization: A noiseless patient Spider Lines: 35 Message-ID: References: <97s96j5fajs26f6eg9odqs48skgghoson5@4ax.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Sun, 09 Jun 2024 15:15:45 +0200 (CEST) Injection-Info: dont-email.me; posting-host="720586a5e635f27f2c1c5d0e1b7a3f22"; logging-data="3631973"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+eyWEJQev3VMsQa8eTfjodY57qb2WeCEE=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:bsfdGcT7CNwwMfp23TKPvc+a6M0= Content-Language: en-US In-Reply-To: X-Antivirus-Status: Clean X-Antivirus: Norton (VPS 240608-6, 8/6/2024), Outbound message Bytes: 2511 On 9/06/2024 8:19 pm, Cursitor Doom wrote: > On Sat, 08 Jun 2024 17:06:18 -0700, john larkin wrote: > >> On Sat, 8 Jun 2024 22:54:07 +0100, John R Walliker >> wrote: >> >>> On 08/06/2024 22:47, John R Walliker wrote: >>>> On 08/06/2024 20:43, john larkin wrote: >>>>> On Sat, 8 Jun 2024 18:10:59 -0000 (UTC), Cursitor Doom >>>>> wrote: >> Shining Star makes nice cheap edge-launch SMAs and SMBs. A proper pad >> stack keeps things 50 ohms. > > Could you possibly expand on that last sentence, please? I've never > encountered a 'pad stack' before. You need to manage the transition between 50R transmission line in the cable and the 50R trace in the board. Traces buried in the board can be non-dispersive, and you can work out how wide the trace has to be and how far from ground planes that carry the return current to get you 50R. A connector on the edge of the board needs special care. The pad stack is a collection of metalised areas in the edge of the board that provide a more-or-less seamless transition. -- Bill Sloman, Sydney -- This email has been checked for viruses by Norton antivirus software. www.norton.com