From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id b8f38234 for ; Mon, 11 Mar 2019 21:48:29 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 541BC94BFE; Tue, 12 Mar 2019 07:48:28 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id C359A94BEA; Tue, 12 Mar 2019 07:47:58 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="key not found in DNS" (0-bit key; unprotected) header.d=bitsavers.org header.i=aek@bitsavers.org header.b="exwbs27B"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id C05F194BEA; Tue, 12 Mar 2019 07:47:55 +1000 (AEST) Received: from ezwind.net (smtp.ezwind.net [71.91.242.96]) by minnie.tuhs.org (Postfix) with ESMTPS id 5392894BE9 for ; Tue, 12 Mar 2019 07:47:54 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/relaxed; d=bitsavers.org; s=MDaemon; t=1552340869; x=1552945669; i=aek@bitsavers.org; q=dns/txt; h=Subject:To:References:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To:Content-Type: Content-Language:Content-Transfer-Encoding; bh=1KdTI/YoDYpwDbtFg YNA8xiteyGwfS/k4tgwer1iSsM=; b=exwbs27B/BHSunsyfLD26Ko0M64zuCI1D 8odo2/b282WrsLChdWynbfGSP2y+WSZyVN3VygDmYlhOnbWvc97NvemVQhkdEQfH kpyENuS9ZrjYsF95Yj3ht8l3yxl7MpYfnKS5otE+DhF5XLsZ2T2JQ8HRp+buSaKF a9CfUZYbB4= X-MDAV-Result: clean X-MDAV-Processed: ezwind.net, Mon, 11 Mar 2019 16:47:49 -0500 Received: from aekmac.local by ezwind.net (MDaemon PRO v16.0.4) with ESMTPA id 18-md50000047277.msg for ; Mon, 11 Mar 2019 16:47:48 -0500 X-MDRemoteIP: 71.6.95.114 X-MDHelo: aekmac.local X-MDArrival-Date: Mon, 11 Mar 2019 16:47:48 -0500 X-Authenticated-Sender: aek@bitsavers.org X-Return-Path: prvs=19735d0e76=aek@bitsavers.org X-Envelope-From: aek@bitsavers.org X-MDaemon-Deliver-To: tuhs@minnie.tuhs.org X-CAV-Result: clean To: tuhs@minnie.tuhs.org References: <201903100731.x2A7VZJF033832@ducky.net> <7wpnqzj7tr.fsf@junk.nocrew.org> <201903102253.x2AMrks8039290@ducky.net> From: Al Kossow Message-ID: <29db723b-91f8-c7fa-591e-5ac383bffab0@bitsavers.org> Date: Mon, 11 Mar 2019 14:47:55 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:60.0) Gecko/20100101 Thunderbird/60.5.3 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [TUHS] a possible source for 4.1BSD tapes X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On 3/10/19 10:46 PM, Jason Stevens wrote: > is there a kyrolux like device for tapes? The problem is dropouts from either tape surface contamination or oxide loss, tape skew, and tape stretch. I've been working off and on with Len Shustek on analog digitization and recovery of 7 and 9 track tape https://github.com/LenShustek/readtape to try to deal with tape that has signal degradation He and I use Saleae Pro Logic 16 USB 16-channel USB setups connected to the read amps of a tape drive I have a Linux box set up with 128gb of memory for data capture. It is a time-consuming process, and I only resort to that for high-value problem children.