Author Archives: gmcdavid

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About gmcdavid

Retired IT professional with a wide range of interests. Married. Three sons, two with autistic-spectrum disorders and the third being transgender with Ehlers-Danlos syndrome. From Chicago but now living in the Twin Cities metro, Minnesota. Episcopalian. Carleton College (BA 1972, physics) and Stanford University (MS 1974, Applied Physics; MS 1976 Statistics).

More Storage Upgrades

I got a new 1TB SSD drive for Christmas. I used it to replace the 512GB drive that I had installed on my HP EliteDesk 705 G2 SFF system. That 512GB drive in turn went back to the old laptop I had taken it from. In both cases the copying was done by Macrium Reflect Free. There were no problems at all with the HP desktop, but the laptop refused to boot afterwards. So I got out my Linux USB boot repair stick and booted from that, ran the boot repair utility and everything was fine. Both Windows 10 and Ubuntu Linux 20.04 booted cleanly.

So I now have two extra 256GB SSD drives. Don’t really know what I will do with them. For now they are mounted in enclosures with USD 3.x connections.

A web site that time forgot

Many years ago I used Slackware Linux. I switched to Ubuntu because I was concerned that Slackware seemed to be essentially a one man show, and that seemed like a single point of failure. But Slackware was good to me, and I have not forgotten it. Recently Slackware came out with a new and up to date release and I am looking at it again.

The web site looks much like what I remember from 15-20 years ago. That is OK with me, although I would like to see some more current content. I decided to download the Slackware book in its pdf form. Firefox just hung when I went to that page. However, I noticed that it was an ftp site, not http. 20 years ago I was accustomed to accessing ftp sites using ftp tools, not web browsers. So I guessed that this was what once known as an anonymous ftp site, and that such sites could be accessed with the ftp command line. Feeling like Gandalf recalling a thousand year old spell, I opened a Linux terminal window and proceeded to type:

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Capricon Notes

As I wrote previously , Mia (my wife) and I spent last weekend at Capricon, a Chicagoland science fiction convention. We went to most of the Capricons in the ’80’s and ’90’s, but in our first years in Minnesota the pressures of parenthood prevented us from going. Those have eased somewhat and we have been to most of the Capricons (and Windycons) since 2009. While most Capricons have been in the Chicago suburbs, this year the convention was downtown, at the Sheraton Grand Hotel.

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Chicago again

Mia (my wife) and I spent last weekend in Chicago for the Capricon, another science fiction convention that has been part of our life for decades. This year the convention was downtown, at the Sheraton Grand Hotel. Our room was on north side of the 28th floor and the view from our window was magnificent by night and day:

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Rang Gaeilge, 26ú lá mí na Eanáir 2022

Duinnín i Ráth Maonais (tuilleadh)

Also Duinnín i Ráth Maonais

  • ‘Charlotte Lehane a d’aimsigh an corpan, a Athair.’
    ‘Mar sin é, a Sheosaimh?’
    ‘Níorbh fhéidir lei – deir sí – ligint dá comharsa an séú
    haithne a bhriseadh os comhair an tsaoil gan comhairle a leasa a
    chur uirthi. Ní túisce X imithe nár gur thrasnaigh Charlotte an
    bóthar. Chnag sí ar an doras – tá a méarlorg ar an gcnagaire.
    Nuair nach bhfuair sí freagra thuig sí go raibh náire ar an
    bpeacach roimpi. Chuaigh sí thart ar chúl an tí, grásta Dé á
    spreagadh, a deir sí. Bhí a fhios aici cá mbeadh eochair an
    chúldorais. Bhíodh sí mór le Nellie gur éirigh eatarthu i ngeall
    ar John Pinkerton. Isteach lei sa chistin. Bhí Nellie ar an urlar
    roimpi, marbh más fior.’

    ‘Charlotte Lehane found the body, Father.’
    ‘So that’s it, Joseph?’
    ‘She couldn’t – she says – allow her neighbor to break the sixth commandment in front of the world without giving her advice for her well-being. No sooner had X gone than Charlotte crossed the road. She knocked on the door – her fingerprint is on the knocker. When she did not receive an answer, she understood that the sinner before her was ashamed. She walked around the back of the house, inspired by God’s grace, she says. She knew where the back door key would be. She was friendly with Nellie until they quarreled on account of John Pinkerton. Into the kitchen. Nellie was on the floor
    before her, dead as it were.’

    ligint
    comharsa neighbor f
    séú sixth m
    aithne acquaintance, commandment f
    comhairle Advice, counsel; direction, influence f
    leas Good, well-being, benefit, interest m gs leasa
    túisce
    trasnaigh Cross; traverse, intersect; Contradict; interrupt, heckle; interfere
    náire shame f
    peacach sinner m
    grásta grace m
    spreag Urge, incite; arouse, inspire; prompt, encourage
    i ngeall in pledge
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Black Hole Lifetimes

Black holes are not totally black! They will evaporate by Hawking radiation. This is required by Thermodynamics and Quantum Mechanics. All properties of a Schwarzschild black hole are determined by its mass, so if you know the mass the lifetime and other properties follow automatically. Or you can start with the lifetime and determine the initial mass. Or the Schwarzschild radius, or the temperature, or the entropy, etc. For black holes comparable in mass to “normal” astronomical objects this lifetime is much longer than the current age of the universe. Viktor Toth’s Hawking radiation calculator is a convenient tool for such calculations. Here are some results:

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Adding a second internal SSD drive to a system

Having done a memory upgrade to my HP EliteDesk 705 G2 SFF system, it was time to add more storage. It came with a 256GB SSD, and I added the 512GB that I had taken from an old laptop. Since I was leaving the original drive in place and simply adding a drive, the process was much simpler than in the drive replacements I have done. The whole thing would have been trivial if I had put the new drive in an external USB 3 adapter. USB 3 is fast, but imposing the USB/SATA conversion would add some overhead, so I decided to open up the machine and make another SATA connection. There was a free SATA power connector inside, but I had to add an extension cable to reach any plausible place to put a new drive. Fortunately, there was a free SATA data cable already present. I put the new drive into a 2.5″/3.5″ mount, but there were no holes to screw it into the obvious place. This is a problem I have faced before, and I used the same remedy: Duct tape.
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Downsizing a disk

I have an old laptop which I do not use often. I had installed a 512GB SSD on it, but decided to replace it with a 256GB SSD so I could use the larger drive on a more modern system. Once again, I planned to used Macrium Reflect Free to clone the drive. This is a lot harder when you want to clone a larger drive to a smaller one. I had to delete my Linux partitions and shrink the Windows one with gparted on my Linux boot repair disk. My total space in use was well under 256GB but Macrium still objected. Examination revealed that I had forgotten to shrink the extended partition in which my Linux partitions had resided. So I fixed that. Still no joy. There was a big (>256GB) gap between the end of the extended partition and the last Windows partition. So I moved that partition inward to leave all the free space at the end. This finally satisfied Macrium Reflect Free and it was able to clone the drive.

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Rang Gaeilge, 17ú lá Mí na Samhna 2021

Duinnín i Ráth Maonais

Also Duinnín i Ráth Maonais


Fairim … I watch, guard; notice, perceive; spy (with ar); I wake or hold a wake on; I keep a thing from (ar); Tá sé ag faire na taoide ar an dtráigh, he is endeavoring to keep the tide away from the strand, attempting to do the impossible (Con.); ag faire an chait ar an mbainne … sean-duine ‘na chodladh agus seana-bhean ag faire uirthe féin … d’fhaireas go bhfaca é …. [the cat watching for milk…an old person asleep and an old woman watching herself … I watched him see it.]


  • Ní raibh an tAthair Pádraig O Duinnín rócheanúil ar Miss
    Charlotte Lehane a raibh cónaí uirthi i Lána na Sceach, Ráth
    Maonais. Mar sin féin, shuíodh sé ina parlús – seomra tosaigh
    dorcha, troscánshactha – uair sa ráithe, nó mar sin, agus
    thugadh sé deis di sceitheadh uirthi féin. Lig sí uirthi riamh
    nach raibh ach gannchuid Gaelainne aici

    ‘Mummy, and Daddy didn’t speak Irish but the servant girl did…’

    Father Patrick Dineen was not too fond of Miss Charlotte Lehane
    who lived in Thornbush Lane, Rathmines. Even so, he used to sit in her parlor –
    a dark front room, stuffed furniture -once a quarter, or so,
    he gave her a chance to express/explode herself. She always pretended to
    speak only a little bit of Irish.

    ‘Mummy and Daddy didn’t speak Irish but the servant girl did…’

    ceanúil Loving, affectionate
    Sceach Thorn-bush f
    Mar sin féin Even so
    troscán furniture m
    ráithe Three-month period, quarter, season f
    Gaelainn = gaeilge
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