# Energy needs of UNIVAC type computers **URL:** \ **Category:** Factual Questions\ **Created:** [November 21, 2023, 11:44pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501 "2023-11-21T23:44:59Z")\ **Posts on this page:** 20\ **Page:** 6
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [December 21, 2023, 9:33pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/101 "2023-12-21T21:33:28Z")
I’d worry about some rando who never read the contract flipping the switch. Back then they didn’t have phone home capabilities so the company would only find out during service calls. Today it would get done through an encrypted diag interface, so this wouldn’t be an issue. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 21, 2023, 10:17pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/102 "2023-12-21T22:17:41Z")
> [@Voyager](#): > > Back then they didn’t have phone home capabilities so the company would only find out during service calls. They were on-site often enough they’d find out. That’s why a board change might have been done for some cases. But messing with IBM service was not a good idea in those days when they owned the world and plenty of sites had no internal service personnel. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [December 22, 2023, 2:18pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/103 "2023-12-22T14:18:03Z")
In most cases you didn’t own the hardware. You leased it. If you screwed with them the movers would show up and take their toys home. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [December 22, 2023, 4:18pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/104 "2023-12-22T16:18:53Z")
I’m not sure most, but it was definitely a thing. Like your telephone equipment. In the Bell System days we built things sturdy so that it would never have to be replaced, and keep earning rental revenue. After the split I went to a talk about how to build quality out of equipment because when we sold the stuff it no longer made sense to spend extra so it never broke. One thing that happened is that people bought crap, cheap phones because their model was that a telephone almost never broke. When they did they came back to AT&T phones which were at least slightly better. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [December 23, 2023, 12:43am UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/105 "2023-12-23T00:43:38Z")
> [@Voyager](#): > > In the Bell System days we built things sturdy so that it would never have to be replaced, and keep earning rental revenue. The thing about a monopoly is that you can force people to buy more quality than they want, even past the point where it’s a _negative_ to them. A Model 500 feels like it contains a small telephone exchange and undoubtedly had a cost to match. They may have never broken down, and could survive a nuclear war, but that’s at odds with a device that doesn’t tire out your arm or send you to the hospital if it does land on your foot (I note that the Wikipedia article on the 500 says “Model 500s are featured as a weapon in the movie _True Lies_”). ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [December 23, 2023, 1:30am UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/106 "2023-12-23T01:30:13Z")
I went to a meeting once with a bunch of people who had been in the division working with small companies who leased PBXs - and the stories I heard were awful. Back when the telephone was a lifeline building in quality made a lot of sense. But it spread. We had terminals (with screens) from Teletype to communicate with our super-mini. Drop one of those armor-plated keyboards on your lap and you could easily damage yourself. That was unneeded quality. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [December 23, 2023, 2:08am UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/107 "2023-12-23T02:08:54Z")
The first IBM keyboards for the PC were like that. I loved them for the key action. In fact, I still have one somewhere with the old round keyboard connector But there is no point in designing computer or telephone hardware to last for decades, because they become obsolete long before. If I know I will be replacing my phone or computer every few years, I don’t want to pay for a design intended to last for 50 years. That said, I bought a set of Panasonic DECT portable phones maybe 15-20 years ago, and everything about them is still working flawlessly. The batteries were AAA rechargeables, and I’ve replaced them all twice now. But the phones themselves all still look and work like new. I suspect they will outlive me, or at least outlive our desire to maintain a land line. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [December 23, 2023, 5:03pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/108 "2023-12-23T17:03:29Z")
> [@Sam\_Stone](#): > > But there is no point in designing computer or telephone hardware to last for decades, because they become obsolete long before. If I know I will be replacing my phone or computer every few years, I don’t want to pay for a design intended to last for 50 years. But if you have a monopoly and upgrading technology won’t make you any more money, then you won’t improve the technology to make your base obsolete. (Called don’t churn the base by my colleagues.) Princess phones were made to try to get people to add more extensions to their homes, and thus charge them more. Touch tone speeds dialing which the customer doesn’t get charged for and thus allows more calls to go through the network. Features which didn’t add revenue until there was competition didn’t get included. An old rotary phone which the customer didn’t pay for upfront but rented and which could last for decades with no service was a real cash cow, ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [December 23, 2023, 7:23pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/109 "2023-12-23T19:23:41Z")
This makes me remember something from my childhood. People were just recently being allowed to buy their own phones. My grandmother got one at a green stamp store, and you had to call the phone company and “register” that you were using a 3rd party phone (this was outside of stopping renting the company’s phone). Did that actually involve them _doing_ anything to the signal on their end, or was it pure bs? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 23, 2023, 8:01pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/110 "2023-12-23T20:01:28Z")
There’s nothing they could have done electronically, but they could have said “Well, this house isn’t renting from us any more and hasn’t registered a third-party phone, so they must not have any legitimate phone, so we’ll cut off their service (but keep sending them a bill)”. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 23, 2023, 9:10pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/111 "2023-12-23T21:10:03Z")
My dad was too “frugal” to pay for touch-tone service. I bought a “slimline” phone at a hamfest, and plugged it in, and it worked. Years later, the phone guys were out fixing something at the house, and noticed the phone, and said “hey, you aren’t paying for that!l, and tried to bill my folks for back service. My dad just laughed, and said “no, I’m not going to pay that.” The phone company never pressed the issue. I suspect it was at the tail end of their monopoly. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [December 23, 2023, 9:45pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/112 "2023-12-23T21:45:23Z")
You’d better watch out for the Telephone Detector Van from the Ministry of Housinge. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 23, 2023, 9:54pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/113 "2023-12-23T21:54:40Z")
A lot of the early push-button phones had a dial compatibility mode, where you’d push the button, but the phone would then transmit a series of clicks, the same as a dial phone would. Apparently at least some phone companies actively disabled tone dialing for customers who weren’t paying for it. ---
**Author:** ![JohnGalt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johngalt/32/184_2.png) [@JohnGalt](https://boards.straightdope.com/u/JohnGalt)\ **Post date:** [December 23, 2023, 10:50pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/114 "2023-12-23T22:50:20Z")
There was a thing called REN: Ring Equivalent Number, which had to do with the power required to “ring” the phone. I recall buying a phone in the early 1980s and reporting that number to the phone company. I don’t know if they did anything about it. The REN was printed on the bottom of the phone. It had an option to turn off the ringer completely, and to switch from touch-tone to pulse dialing. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [December 23, 2023, 11:12pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/115 "2023-12-23T23:12:21Z")
I am not sure what the formal definition of that is, but I did find a PDF that defined it as 1 μF in series with a 4 kΩ resistor. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 23, 2023, 11:34pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/116 "2023-12-23T23:34:09Z")
Dad said he’d never seen some many bleeding aerials! ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [December 23, 2023, 11:50pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/117 "2023-12-23T23:50:04Z")
> [@JohnGalt](#): > > I don’t know if they did anything about it. I think that in theory, they needed to know if you were in danger of pulling down too much ringing current because of all the ringer circuits in parallel on the end of your line. But it never seemed to make a difference. By the time people had enough phone instruments on their circuit for it to matter, they were probably all purely electronic ringers with ridiculously low REN values compared to the old-school electromechanical ringers. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [December 23, 2023, 11:55pm UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/118 "2023-12-23T23:55:04Z")
There is, of course, a wiki. > **[Ringer equivalence number](https://en.wikipedia.org/wiki/Ringer_equivalence_number)** > > The ringer equivalence number (REN) is a telecommunications measure that represents the electrical loading effect of a telephone ringer on a telephone line. In the United States, ringer equivalence was first defined by U.S. Code of Federal Regulations, Title 47, Part 68, based on the load that a standard Bell System model 500 telephone represented, and was later determined in accordance with specification ANSI/TIA-968-B (August 2009). Measurement systems analogous to the REN exist internationall... ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [December 30, 2023, 10:09am UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/119 "2023-12-30T10:09:38Z")
> [@gnoitall](#): > > I think that in theory, they needed to know if you were in danger of pulling down too much ringing current because of all the ringer circuits in parallel on the end of your line. > > But it never seemed to make a difference. It could make a difference. When we built the indoor arena and 3rd horse barn on our farm, between the house business, barns & dog kennel, there were 9 phones + a loud outdoor ringer box connected – all 500 or 554 models – on the line, about 2 miles out of town. But that last phone added made the ringers stop working properly. They gave a strangled, anemic sort of ring. So a phone worker came and checked the line. He adjusted something in the connections box at the end of the driveway, but basically said there just were too many ringers on the line. He suggested disconnecting the ringer on some phones in the house that were within hearing distance of other phones, and that seemed to solve the problem. It worked for another decade or so. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [December 30, 2023, 10:20am UTC](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501/120 "2023-12-30T10:20:32Z")
> [@Sam\_Stone](#): > > The first IBM keyboards for the PC were like that. I loved them for the key action. In fact, I still have one somewhere with the old round keyboard connector > > But there is no point in designing computer or telephone hardware to last for decades, because they become obsolete long before. But a keyboard doesn’t go obsolete! The tactile feel and responsiveness of those old IBM keyboards is so good – I’m still using using one though the computer it’s connected to has been replaced 3 or 4 times. And it’s built well enough that it will probably last through several more upgrades. And you can still buy new versions of those keyboards from a company called UniComp (IBM employees who bought the factory & equipment when IBM closed it down)[www.pckeyboard.com](http://www.pckeyboard.com) And if you still have an original one with the round PS/2 cord connector, you can buy an adaptor that converts it to a USB connector to plug into any current computer. [Previous page](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501.md?page=5) [Next page](https://boards.straightdope.com/t/energy-needs-of-univac-type-computers/993501.md?page=7)