From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FROM,HTML_MESSAGE,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 8351 invoked from network); 29 Mar 2021 22:30:15 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 29 Mar 2021 22:30:15 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 89EEE9C835; Tue, 30 Mar 2021 08:30:14 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 94DF99C82B; Tue, 30 Mar 2021 08:29:54 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="fTOgIQmW"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 10E029C82B; Tue, 30 Mar 2021 08:29:51 +1000 (AEST) Received: from mail-yb1-f179.google.com (mail-yb1-f179.google.com [209.85.219.179]) by minnie.tuhs.org (Postfix) with ESMTPS id 4A7669C829 for ; Tue, 30 Mar 2021 08:29:50 +1000 (AEST) Received: by mail-yb1-f179.google.com with SMTP id l15so15428637ybm.0 for ; Mon, 29 Mar 2021 15:29:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=h1wpK7mzSuERYiGyYlAcsxD/ZUcaCRiOJE/UyHgXXlY=; b=fTOgIQmWjhTYsjOspQg7o+Fkh8cMiOZXWRfLc/eDGCgT7gEfE5V8sDSs3RqNQpozJ5 CRfVuJxngDcVzfephHUYAA1v4vPDzJIxq6wIrBe5GPEL3Wyfs5A07EHegAkvdWEQHix9 Lu1giqY3BDgdboXlWdbGKBFi1x5irB4Z1wDOqsEoF3IicfuLYPOSArFHQfHtNeEEIAYX pz4NJL96frlLbdf+bEhA9w8zbgKvURPLMwuPHJRO3c4BOMysY4LrEKJydZvQ5kak3mKF ZYb9xzaQfY386iHSWrxLF/LZTKw7K5U/Kx5jRi3KHKI+KZZBHUBHxmFFxUHIoVf3euIv iymw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=h1wpK7mzSuERYiGyYlAcsxD/ZUcaCRiOJE/UyHgXXlY=; b=drz475xesjA8S7R08mnGecO0q3NsSiBf83hroeo3t5xQF4Gvc2LgmTMGl5xNgaNjoI GBjvE1kSaYCVqJFmmmWDEnjJj3myXDIs+uQZp0wPchf6JSEJn6BXdwhD0W4RoajH9qYZ dCQoRxYTiJX9/wYTaCHNmmOLLMDDrsZb6pGI8Ni3QqL65WU4j6TucWuLiMEbUwA88JRY ALrZ+jeMgB2tkxmFmwlQRHNro4XtZLn1Wbt2E7CldZjGXWwWPyRUGaC4Xn1m2JiszHnj KFgwjPFY03vnFekqtxI/Rr/BCT47X7O6QP82CwvHeotfh13zj4I4Nv/Pm/H+EgyWObWZ EKBg== X-Gm-Message-State: AOAM530L/RMWMJDQHk1j7N9kp0DAZIxLwuMNEKFCfQ8nk1WEqfF9uyOQ 0hZvqkjtWlZdGtGzTIFAFRiOKgJtqxpIdFvfV0o= X-Google-Smtp-Source: ABdhPJw2mvxwqLM/byexTD5RpDBNrV4FnthvRaJGMYKZ9zSR4TUxgENuKIED4tYhzfI09YNcjcijpbA8TzF4szzhpy8= X-Received: by 2002:a25:e812:: with SMTP id k18mr29656062ybd.201.1617056989213; Mon, 29 Mar 2021 15:29:49 -0700 (PDT) MIME-Version: 1.0 References: <4B1F03CA-6387-4FE1-8116-0CB7B5175DE7@ucsc.edu> <20210329205559.GI4209@mcvoy.com> <20718.1617052215@cesium.clock.org> In-Reply-To: From: "John P. Linderman" Date: Mon, 29 Mar 2021 18:29:37 -0400 Message-ID: To: Clem Cole Content-Type: multipart/alternative; boundary="0000000000006c778d05beb46bcb" Subject: Re: [TUHS] Remember the ed thread? 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: , Cc: TUHS main list Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" --0000000000006c778d05beb46bcb Content-Type: text/plain; charset="UTF-8" > > > On Mon, Mar 29, 2021 at 5:16 PM Erik E. Fair wrote: > > Line printers are distinguished not by the width of the paper but by the >> printer having enough print heads to print an entire line of output at a >> time. That speed advantage made them the preferred output device for >> many-page program listings, as opposed to a teleprinter terminals which >> were more suitable for interactive computing. >> > There were originally two styles, the drum printers which DEC sold(e.g. > LP20) and the chain printers that IBM offered (e.g. 1401). The drum had > all the characters in each of the 132 columns (the upper case only printers > were faster because the alphabet was on the drum in two places). The IBM ones > has slugs on a rapidly spinning chain that was horizontal (and parallel) > to the line being printed. The chain was easily replaceable by the > operator - which was one of the duties we would have. When a user queued a > printer a set of symbols (*i.e.* the chain of the needed output > characters) was specified and the system queued it until the printer had > been properly provisioned. For instance, CMU printed checks with a > special chain and film ink, so once a night the operator would configure > the printer, and tell the queue to print them). Some chains were faster > than others, the standard one had N copies of each character. > > In common to both schemes is that each both styles had 132 hammers and > when the proper character was in the position needed, the hammer fired to > make an impression the ribbon on the paper, which was caused the noise > people associated with computer printers. The high-end IBM 1401 had a > hydraulic cover that came down over it and was controlled by the channel > processor (it would auto-open when it needed to be serviced - like a new > box of paper). > > This led to the "first commandment of fancy printers": Thou shalt not leave thine coffee on top of the printer. -- jpl --0000000000006c778d05beb46bcb Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

On Mon, Mar 29, 2021 at 5:16 PM Erik E. Fair = <fair-tuhs@net= bsd.org> wrote:
=C2=A0
Line printers are distinguished not by the width of the paper but by the pr= inter having enough print heads to print an entire line of output at a time= . That speed advantage made them the preferred output device for many-page = program listings, as opposed to a teleprinter terminals which were more sui= table for interactive computing.
There were originally two styles, the drum printers which DEC sold(e= .g. LP20)=C2=A0 and the chain printers that IBM offered (e.g. 1401).=C2=A0 = The drum had all the characters in each of the 132 columns (the upper=C2=A0= case only printers were faster=C2=A0b= ecause the alphabet was on the drum in two places).=C2=A0 The IBM ones has slugs on a rapi= dly spinning chain that=C2=A0was horizontal (a= nd parallel) to the line being= = printed.=C2=A0 =C2=A0 The chain was easily replaceable by the operator - wh= ich was one of the duties we would have.=C2=A0 When a user queued a printer= a set of symbols (i.e. the chain of the needed output characters) wa= s specified and the system queued it until the printer had been properly pr= ovisioned.=C2=A0 =C2=A0For instance, CMU printed checks=C2=A0with a special= chain and film ink, so once a night the operator would configure the print= er, and tell the queue to print them).=C2=A0 Some chains were faster than o= thers, the standard one had N copies of each character.

In common to both schemes is that each both styles had 132 hammers = and when the proper character was in the position needed, the hammer fired = to make an impression the ribbon on the paper, which was caused the noise p= eople associated with computer printers.=C2=A0 The high-end IBM 1401 had a = hydraulic cover that came down over it and was controlled by the channel pr= ocessor (it would auto-open when it needed to be serviced - like a new box = of paper).

= This led to the &qu= ot;first commandment of fancy printers": Thou shalt not leave thine co= ffee on top of the printer.=C2=A0-- jpl
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