From owner-freebsd-questions Wed Nov 7 5:44: 8 2001 Delivered-To: freebsd-questions@freebsd.org Received: from smtp1.mx.pitdc1.stargate.net (smtp1.mx.pitdc1.stargate.net [206.210.69.141]) by hub.freebsd.org (Postfix) with SMTP id 491EE37B417 for ; Wed, 7 Nov 2001 05:43:46 -0800 (PST) Received: (qmail 3055 invoked from network); 7 Nov 2001 13:43:53 -0000 Received: from unknown (HELO wastegate.net) (209.166.135.203) by smtp1.mx.pitdc1.stargate.net with SMTP; 7 Nov 2001 13:43:53 -0000 Received: (qmail 46307 invoked from network); 7 Nov 2001 13:43:36 -0000 Received: from unknown (HELO MOTHER) (192.168.1.2) by 192.168.1.1 with SMTP; 7 Nov 2001 13:43:36 -0000 From: "Doug Reynolds" To: "Bill Moran" , "questions@freebsd.org" Date: Wed, 07 Nov 2001 08:42:59 -0500 Reply-To: "Doug Reynolds" X-Mailer: PMMail 98 Professional (2.01.1600) For Windows NT (5.0.2195;2) MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Subject: Re: Welders causing dial-out to fail Message-Id: <20011107134346.491EE37B417@hub.freebsd.org> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Tue, 06 Nov 2001 12:00:37 -0500, Bill Moran wrote: >This may be a little off-topic ... >I have a client who I installed a FreeBSD proxy server for. >It uses pppd to dial out on demand. Right from the start, the >client has been having problems with the reliability of the >dial-out. To make a long story short, after a lot of testing >and speculating, we determined that its electric welders in the >shop causing the problem. There are five resistance welders in >the shop and when all five are working, the Internet connection >is simply unusable. If two or three are in use, the Internet >is slow, the connection drops a lot and has to dial 2 or 3 times >to get a connection. If nobody is welding, the Interenet >connection works perfectly. >The interference exists on all 4 phone lines, it's audable at >times on the voice lines (but never very bad) and has never >been bad enough to disrupt the fax machine. >We had the phone company (Verizon) come in and they basically >said, "Our wiring isn't the problem, you may want to have this >building rewired." >Does anyone have any experience with this kind of thing? Rewiring >the building is pretty much cost-prohibitive. Verizon did install >a noise filter at their junction box, but the improvement is very >minimal. >We're searching a few avenues for a solution, one being the >manufacturers of the welding machines, but I thought I'd put the >question out to this list and see if anyone else has worked through >and found a solution for a problem like this. probably the quickest solution would be to run a shielded CAT5 or CAT5E cable from the interface / phone terminal to your dialup modem bank for all four lines. and verify that when the inside lines are disconnected , the problem isn't happening. and make sure the shield on the cable is grounded. also, you might be able to put some kinda RFI filter on the welders themselves. --- doug reynolds | the maverick | mav@wastegate.net To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message