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 18011 invoked from network); 30 Mar 2021 04:31:36 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 30 Mar 2021 04:31:36 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 4544E9C83A; Tue, 30 Mar 2021 14:31:34 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 591B99C82B; Tue, 30 Mar 2021 14:31:13 +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="STqw/ytm"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 1D5769C82B; Tue, 30 Mar 2021 14:31:11 +1000 (AEST) Received: from mail-lf1-f54.google.com (mail-lf1-f54.google.com [209.85.167.54]) by minnie.tuhs.org (Postfix) with ESMTPS id 1799F9C829 for ; Tue, 30 Mar 2021 14:31:10 +1000 (AEST) Received: by mail-lf1-f54.google.com with SMTP id v15so21730181lfq.5 for ; Mon, 29 Mar 2021 21:31:09 -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=1fFI+oJO75eKpOxUp+NtMq/3TD9HCE91P6NMOKroOcY=; b=STqw/ytmecNttrm9CU1s5yaxgjeV07Nj5lKBhBBO2b6L4YmBhTKPZ8Du0qnSSSEJpC j/WF15f2CK6KerTHHdfK2mfVJac+RvFEyQSIluY0GI19DubkXoDgSpETKZvdghK3jhmn Q0lvr8nnoksdtBj6mcE7Yw1gm8l/hvCfyI2STtW1oyxKWC0EYN9GfHOSYFt6OhoqFv59 xcpAsZhwCsE8QDFfvY3rfZQGOhH5cFGFUE85ZC0U/NyXlft0PzxEXiNdo5i+ThHS3uW6 eAcQMbREElAeOkI3DaUS5TNdMvQmlzJqQjDWiUCxE6W0yrk3dxybDSc/MLf2Mh0NYu81 cU0Q== 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=1fFI+oJO75eKpOxUp+NtMq/3TD9HCE91P6NMOKroOcY=; b=npM9YKoRl0a6n3Ni8W7DuqEmRaUrFhE0i+3S9GIH7MT+yHQWGJD4iu0pJqBCqNmglC IP4rzTvT5bfNfQV8SP4rcCeqorK1Rqnop1yTSaMdrz640x6ynvgaLs4rBG+5gQLvpGCd p77sXWdfxqvJcXOzbtFrgvDGe9HrWgo6HTTfWQ1Nn16LlIoEVrf9bZpKF7bkRLqL5uVE l/Tn7EdGNYCj9/c+C+xAjZFaR/28oLCQv2HswN2Jji2EByAMXlYsaglX2Et8TBqi590d 36qtGgbVVbOImP2oZflPhSs5DiDv6uUXda3QJFoSUohwEkx8XAdvShLO3x+zq/anAjxc eqTQ== X-Gm-Message-State: AOAM530fQDP9rlisKhG9gZWM8oun4j2RJqYk1SAIGcZ0diVy7Zxb8Y59 2aVkGK7AD6WTMJ7iKuobjUAuT0Wr4Cv8Wie30RU= X-Google-Smtp-Source: ABdhPJw1WNMIfmQQqzixI+Zw6uWK5UIm9e8z969Z0twME3tuC8ogbzh+qMQxeD7AQXwb6bTsL/UuGX2NjG0jKzt810U= X-Received: by 2002:ac2:4c85:: with SMTP id d5mr19425585lfl.503.1617078668351; Mon, 29 Mar 2021 21:31:08 -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: Rob Pike Date: Tue, 30 Mar 2021 15:30:56 +1100 Message-ID: To: "John P. Linderman" Content-Type: multipart/alternative; boundary="00000000000099db2b05beb977e0" 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" --00000000000099db2b05beb977e0 Content-Type: text/plain; charset="UTF-8" Night operators were known to nap on top of the 1401s. When there was a need for more paper, they would be gently awakened. -rob On Tue, Mar 30, 2021 at 9:30 AM John P. Linderman wrote: > >> 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 > --00000000000099db2b05beb977e0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Night operators were known to nap on top of the 1401s. Whe= n there was a need for more paper, they would be gently awakened.

<= /div>
-rob


On Tue, Mar 30, 2021 at 9:30 AM John P. = Linderman <jpl.jpl@gmail.com>= ; wrote:

On Mon, Mar 29, 2021 at 5:16 PM Erik E. Fair <fair-tuhs@netbsd.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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