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Showing posts from August, 2023

Luminist.org

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I was reading this page: https://www.newscientist.com/letter/mg15320758-300-letters-patently-first/ about the early semiconductor patents of Lilienfeld in the 1920s/1930s.  It mentions an article in Analog magazine, March 1965.  I then started searching the usual suspects for pdf files of Analog and eventually found this page: here is the link to the ANALOG magazine archives: http://www.luminist.org/archives/SF/AN.htm here is the March 1965 issue:  https://s3.us-west-1.wasabisys.com/luminist/SF/AN/AN_1965_03.pdf Lots of other material on this luminist site, will be back to do more exploring ! Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Programma 101

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I was watching this Asianometry video: source: https://www.youtube.com/watch?v=vfMxcrN90PE but when I saw this: it reminded me of 7th grade at Maple Dale, Mr. O'Keane's math class.  We had one of these machines (a rental or loan ?) - I remember that Mr. O'Keane only had one or two of the magnetic cards.  They seemed so neat, dropped into a slot to be read.  As I recall we also had a mechanical calculator with the chuga-chuga action (don't divide by zero).  This was 1967 or 1968.  It was in a new wing of Maple Dale, new technology, the space program was active, Milwaukee would soon get an NBA franchise - it was really a cool time, stuff was happening !  :) Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Curious Droid video on the cavity magnetron

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This was an interesting video on the cavity magnetron and how it enabled microwave radar during World War II: source: https://www.youtube.com/watch?v=CbTWzC86R4Y I am going to have to re-read Tuxedo Park by Jennet Conant: https://archive.org/details/tuxedoparkwallstcon00cona Tuxedo Park is a biography of Alfred Loomis.  It details his early unofficial involvement in facilitating the development of the cavity magnetron in the US. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

testing lithium coin cells

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 Stepped on the scale one morning and it started blinking Lo  rapidly.  Time to replace the two CR2032 lithium coin cells: But I found this in the drawer: Is this OK or what ?? (yes, I know there's such a thing as written notes but it wasn't done, OK ?) Now I usually use the old reliable (sorta) Sears VOM for this: in fact that's about all I use it for.  But it's not helpful in this case. Looking at the Energizer data sheet for CR2032 I saw this figure: For a load resistor of 30,000 ohms the voltage is very constant at just above 2.8V and then it falls off the table like a Koufax curve ball.  So why not a simple test fixture and the DVM to test the CR2032: It's just a wood clothespin with a small 2-56 bolt through each side, wired to a 10,000 ohm resistor (1 % for some reason) and with two flying leads to the DVM.  Let's try it out, first with the bad cells just removed: they are both below 2.8V.  Next try the unknown cell: It is above 2.8V but just barely, the

I asked Bing for a Washington Island Maple Syrup label

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This is what they gave me: I think I'll pass (I was really only trying to get the points, Bing) Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

boy/girl deaths Nicolet class of 1973

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It's been more than 50 years since graduation there have been some recent deaths reported here: https://www.classcreator.com/Glendale-WI-Nicolet-1973/class_inmemory.cfm 7 of the names on the page are teachers/staff at Nicolet, not part of the class of 1973 so they were excluded from the count. 25 female 54 male -- ------ 79 total deaths Per the graduation program, there were 548 graduates in 1973, 279 boys and 269 girls.  About 14 percent of us have died.  The numbers are imperfect, some of the deaths were people who didn't graduate and my vision isn't that good anymore so the counts may be off. I won't be going to the 50th reunion in September, reasoning is that I remember these people as they were: young, slim and strong with plans for the future, their whole lives ahead of them.  I know it's immature but I just can't feature the people lost, why were they taken and here I remain ?   I blame this post on today being a gloomy Saturday :) afternoon update:  the

Communications Quarterly

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Communications Quarterly was a ham radio technical magazine, I was a subscriber.  It folded at the end of 1999 and somehow was continued as a monthly expanded version of QEX although I'm not sure if any of the people involved moved to QEX though. It was a good magazine while it lasted, maybe more theoretical than practical but interesting.  For example, K6OLG published an article in the Winter 1993 issue about LC testing that used the concept of a shifted oscillator.  This shifted oscillator idea was also used by the very famous AADE LC meter.  K6OLG also mentioned the Tektronix model 130 LC meter which also used this idea.  I have a model 130 around somewhere which I bought from GTE as surplus but it developed a needle palsy - as I recall it had a special tube that was hard to get so I never got the shake fixed. Now Worldradiohistory has scans of all the issues for download: https://worldradiohistory.com/Archive-All-Communications/Communications-Quarterly.htm It's also availab

C3 can do !

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Chandrayaan 3 in orbit of the moon https://arstechnica.com/space/2023/08/india-becomes-the-fourth-country-to-land-a-spacecraft-on-the-moon/ The second time was the charm for the Indian space program after the problems with Chandrayaan-2 and the subsequent pandemic.  The next item on the agenda will be deploying the Pragyam onboard rover.  It was reported to have been released from the lander but no pictures yet, this is the 21st century, need the pictures ! BTW, I remember interviewing at GTE Automatic Electric in Northlake, IL - in the grass just before the security gate the unofficial motto of the plant was planted with flowers (which particular flower I don't remember): AE Can Do Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

RED ALERT (no not the book)

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I reported on the book previously:  https://wb9kzy.blogspot.com/2023/05/book-report-red-alert-by-peter-bryant.html This was from the USPS: I was sending back an item from ebay.  I wonder if it will boomerang back ?  We will see. update 8-26-2023:  yes, the parcel was returned to me, weird. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

New procedure: first read, then think, finally order

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 As often happens, I tried adding a new item at the last minute to a recent Mouser order, a Davies Molding 220 box.  These phenolic beauties have been around since the days of Knight-kit and they make for a nice, solid kit enclosure. However, I didn't read the description, I had been ordering the Davies Molding 220A from my previous supplier.  Mouser doesn't stock the 220A, they stock the 220.  So I ordered the 220 without thinking.  The 220A has four tapped holes for 4-40 hardware.  But when I got the 220, I found out that the holes are tapped for 4-36 hardware.  So it was close but no cigar, kind of like how M3 hardware is almost 4-40 but not really !  Luckily I only bought one. Then I put in a subsequent order to Digi-Key and included some 4-36 screws - the idea was to make lemonade from the Mouser lemon. Looks OK, right ? BZZZZT ! The four screws are torqued down all the way No, I forgot to do my reading, AGAIN.  The 220 holes are only tapped .31" deep so a 5/16"

Landing is hard, crashing is easy, part II

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. Luna-25, the gold is probably only a few atoms thick As previously blogged:  https://wb9kzy.blogspot.com/2023/04/landing-is-hard-crashing-is-easy.html https://arstechnica.com/space/2023/08/russia-seems-to-have-lost-contact-with-its-first-lunar-probe-in-half-a-century/ The strange thing is that the Soviets did an excellent job landing on Venus, no others have even attempted a landing: source: https://www.youtube.com/watch?v=UEmlOjKmL68 Asianometry also took a look at the Soviet attempts on Mars: source: https://www.youtube.com/watch?v=knDT0iqo878 This makes me think that NASA going back to the Moon with Artemis is probably a good idea.  Better to get this landing thing down pat on a relatively close object than to skip the Moon and go directly to Mars. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Borgward video

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  Sometimes the internet still surprises and delights, I thought this video about the German carmaker,  Borgward, was very interesting.  I'd never heard of Borgward before seeing the video.  Certainly by the time the company went out of business, imported cars had become fairly common here in the USA. My Dad had a Volkswagen beetle in the 1960s but I have to say that if I had been choosing and there had been Borgwards, I would have gotten one of them over the Beetle, just the styling alone of the Issabella would have been enough. These days all the cars are SUVs which all look like rolling potatoes to me, just a question of size :) Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Fair Radio closure mentioned in ARRL Letter

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The Fair Radio closure was previously covered here: https://wb9kzy.blogspot.com/2023/08/fair-radio-going-out-of-business.html The ARRL mentioned the pending closure of Fair Radio in the ARRL Letter of August 17, 2023, maybe there's room for hope ?  (see the last line but the blue links won't work, this is a jpg file): BTW, I clicked on the Fair Radio link in the email version and got this screen: So there must have been quite of few hams also clicking at the same time ! The ARRL also included this link to the 1967 Fair Radio catalog on the always wonderful World Radio History site: https://worldradiohistory.com/Archive-Catalogs/Allied-Catalogs/Fair-radio-Sales-67.pdf Here is a picture of some GE transformers I bought from Fair Radio in the 1970s (there's another one behind them that can't be seen)   The idea was to build a cheap 13.8 volt supply for a solid state medium power rig like the SB-104 - I got the transformers mounted, added a rectifier and filter cap but neve

Vital secret order decoded !

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. message source: https://www.facebook.com/groups/907249652996436 . decoder badge source: https://the-wanderling.com/captain_midnight.html My Dad would have been 11 years old in 1941 but not sure if he listened to Captain Midnight or not.  He was always crazy about the Navy and boats so maybe he listened to Don Winslow ?  Or he also liked Tom Mix.  One time he and my Grandpa went to the Tom Mix circus while they were living in Appleton.  The tent came down during the performance, I guess it was scary: BTW, I hope that SPAM (and eggs) had nothing to do with the cholera in Shanghai ! I miss being able to search the Milwaukee Journal archives with Google. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

VE3DNL Marker Generator to TinySA attenuator

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Per the TinySA spec:  https://tinysa.org/wiki/pmwiki.php?n=Main.Specification suggested max input is 0 dbm or 1 milliwatt or .225 volts (rms) at 50 ohms try an input impedance of 300 ohms, output impedance of 50 ohms assume power input of 5 volts peak (actually lower) which is about 1/2 watt or 27dbm so try for 30 db of attenuation ? from this site: https://chemandy.com/calculators/matching-pi-attenuator-calculator.htm . use 327, 2100 and 50 ohm resistors, output is about 54 mV peak (same as RMS since it's a square wave ?) so it should be safe. open circuit, 10x probe (with compensation checked) 30 db of attenuation, should do the trick Now to get an SMA cable for the TinySA. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Measuring output impedance

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 It occurred to me that part of the problem with the VE3DNL Marker Generator and the strength of 10 kHz harmonics at the upper HF range might be due to fixturing: https://wb9kzy.blogspot.com/2023/08/unsolved-mysteries.html   I was using a gimmick cap to connect the TinySA to the VE3DNL, and as a capacitor the response would vary with frequency.  And the VE3DNL output has to be attenuated somehow to avoid damaging the TinySA.  No better way to do this than with a resistive attenuator which shouldn't vary in response the way a simple gimmick cap would. So the first step is to determine what the output impedance of the VE3DNL Marker Generator is.  This site suggested a method: https://electronics.stackexchange.com/questions/6917/measuring-output-impedance Another way of doing this would be to use a pot and vary it until the output decreased by 1/2.  I wasn't so sure any of the pots I have are good enough RF wise for this, so I just used some fixed resistors (50, 150, 252 and 300