A Crummy Commercial

While trying out the varactor crystal set in the evening https://wb9kzy.blogspot.com/2024/07/varactor-crystal-set.html (it was not a good night for listening, t-storms approaching) I noticed a couple of things: 1) My HP 6281a supply was putting out zero volts !  I've mentioned this unit before: https://wb9kzy.blogspot.com/2022/01/the-hp-6281a-power-supply.html Oh no !  It was a very warm/humid evening and I had left the supply on continuously for hours.  Also, I had placed a digital scale on top of the supply, blocking some of the vent holes.  I turned it off and when I retried it this morning it appears to be OK.  Must have just been something overheated - I'll find another place to stow that digital scale and I also started using a 9V battery to power the varactors since the current used is very low. 2) The "utility" audio amplifier I've been using with the crystal set sounds distorted.  I scoped the output - it appears that there is a problem with the positive

It probably doesn't qualify as a real crystal set since 9 volt power is applied to the varactors but here is a quick set that I lashed up: Here is a scope pic of WDBC 680 kHz Escanaba: WDBC is about the only AM station I can get during the day on a crystal set.  Using a 40 meter dipole lying on the ground as an antenna and the ground connection was made to the power strip ground.  I will have to re-try it tonight and see what else can be heard.   I didn't get a chance to try the Mikrowave1 design: https://wb9kzy.blogspot.com/2024/07/varactor-crystal-set-video.html Just used a 260 uH coil wound on an old large pill bottle.  A Radio Shack 1n34 was then hooked to a tap on the coil.  No primary winding was used but I did add a 113 pF cap between the LC and the antenna which seems to help with sharpening up the response of the LC circuit.  Two 1SV149 varactors are used in series and they are controlled through a 100k ohm resistor by a 10 turn, 10k ohm pot connected to the 9.2V power

Jordan Love's new employment contract money breakdown (to play quarterback for the Packers): source: https://twitter.com/KenIngalls/status/1817930973129929002   mentioned before: https://wb9kzy.blogspot.com/2024/06/jordan-love-rumored-contract-numbers.html   https://wb9kzy.blogspot.com/2024/06/lucky-strike-extra-jordan-love-rumored.html   I wonder if the older sportswriters like Tom Silverstein or Pete Dougherty knew they would have to study accounting to report on football ?  Conversely, do current sports journalists in school have special classes in contract law ?  :) And Jordan will probably get to do paid endorsements (although those can't be too lucrative in Green Bay unless it's a national account like State Farm). But really, what do I care ? Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

I did do a little more testing on the 1SV149 varactor diode from the previous blog: https://wb9kzy.blogspot.com/2024/07/b-cap-meter-has-feet-of-clay.html The part does basically meet the spec, 25 pF at 8 volts and 396 pF at 1 volt.  Need to realize that the actual 1sV149 values are a little higher due to the series .01 uF cap. However the crystal set didn't work that well, kind of a lousy response with an antenna coil out of an old GE tube radio.  Only got one station at 680 kHz (WDBC) and that didn't really peak like it should.  Then I did a little searching and found this video by Mikrowave1: source: https://www.youtube.com/watch?v=AaPdHu-Dsio He uses two varactors with the cathodes connected (a series circuit) which eliminated the need for the .01 uF DC blocking cap of the W0XI circuit with the single varactor.  However it also halves the resulting capacitance so with a crystal set the coil value must be larger.  He uses this design: I will have to scare up another 1sv149 an

Finally tried the W0XI Tidbit for a Varactor cap for AM radio.  I poked through my bag of diodes and found a 1SV149 which is meant for AM radio use.  The Toshiba datasheet: source: https://www.alldatasheet.com/datasheet-pdf/pdf/29858/TOSHIBA/1SV149.html Here is the circuit again from W0XI: source: https://wb9kzy.blogspot.com/2024/02/w0xi-circuit-tidbits.html I tried measuring the capacitance at the voltage limits (I didn't realize that the specs were at 1V and 8V so will have to get that data for another post)  using a shifted oscillator type of LC meter similar to the AADE unit.  I got the following results: 23 pF at 9.2 volts . 617 pF at zero volts Then for the heck of it, got out the B&K 810C capacitance meter and tried it.  The results were way off - also it affected the LC meter readings which had been left in the circuit: both read too high at 9.2 volts , similarly the readings are both too high at zero volts I also disconnected and turned off the LC meter but the B&K

Sometimes the Youtube overlord serves up something new that is actually funny: source:  https://www.youtube.com/watch?v=tXww7x1wO3g Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Although I still haven't ordered the correct crystals I thought I would try the PA2OHH marker generator circuit but sub an AND gate for the diodes: Here it is on the breadboard:   While this doubles the chip count it does yield a cleaner looking output (pin 12 of the 74HC4060): . a zoom into the center blip, about 25 nS wide I used a 74HC00 NAND gate because I didn't have an AND gate on hand.  The second gate inverts the output from the first 2 input NAND to an AND.  The other two gates have their inputs tied high to minimize power consumption.  R3, the 10k resistor was added for when neither of the upper 2 jumpers is used and provides a logic 1 to provide inversion through the gate. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

I did finally try out the PA2OHH circuit previously blogged on here: https://wb9kzy.blogspot.com/2024/07/a-closer-look-at-pa2ohh-marker.html Here again is the circuit: I looked through the crystals I have on hand and ended up using a 5.12 MHz crystal Here it is on the breadboard: There is a mistake in the top diode polarity in that picture so only the pin 6 output is being looked at - the frequency is nominally 80 kHz (no trimmer was used to get the output more accurate).  See scope captures here: zoom in on the center spike to see the pulse width correcting the polarity of the second diode on pin 13 the frequency drops to nominally 16 kHz - that's a division of 5 rather than a binary division of 4.  Unfortunately as can be seen on the photos, the output is not a pure spike, the positive blip is from the pin 6 output being ANDed together with pin 13 using diodes - if a gate had been used the waveform might be cleaner but also the circuit would be more complex.  Here are the scope c

This is a really cool article: https://arstechnica.com/science/2024/07/were-building-thermonuclear-spaceships-again-this-time-for-real/ DRACO from NASA/DARPA source: https://en.wikipedia.org/wiki/Nuclear_thermal_rocket Atomic spaceships cruising the solar system !  Just like in the Heinlein stories - I recently listened to The Green Hills of Earth: https://archive.org/details/xminusoneotr/X_Minus_One-The_Green_Hills_of_Earth.mp3 where the hero is blinded by radiation from an atomic rocket motor. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm  

I was looking at the book:  Run to Daylight   again since the Packers start training camp today: first blog mention:  https://wb9kzy.blogspot.com/2022/10/some-thoughts-on-run-to-daylight.html One thing with the Archive books, OCR gets done automagically during the upload process - this makes it easy to search, for example, how to go: quoted 15 times in the book.  I suppose it's something like a shortening of:  "That's how to go about it"   Maybe not :)  Is it an east coast thing that blew in with Vince ?  Or maybe something from the 1950s ?  Internet searches are worthless for  finding more info on this kind of thing.    "Way to go" is what we said when I was a kid in Wisconsin, usually in a mocking tone:  "way to go, Chuck, way to drop your lunch tray"   Way to go is quoted only 4 times: Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

I was looking at this photo: The only ones I recognize are Bergen and McCarthy source:  https://www.facebook.com/groups/1064589890390475/ and at first I thought that everyone was wearing clothes with pinstripes - but then I realized that the narrow white stripes were all over the picture and must be some artifact of either scanning or transmission.  The only person wearing striped clothing is the woman to the right of Charlie McCarthy (the ventriloquists dummy). So I tried doing a visual search with the picture but found nothing better online.  However I came upon this photo: name your musical group: Heine and the Grenadiers ?  Yes, it is Milwaukee source:  http://theradiohistorian.org/wtmjgallery/images/wtmjgrenadiers.jpg from this interesting page: http://theradiohistorian.org/wtmjgallery/wtmjgallery1.html I hadn't thought of Radio City for a long time.  Radio City had studios and the headquarters of WTMJ in Milwaukee.  It was located on the west side of the Milwaukee river on Ca

I saw this video: source: https://www.youtube.com/shorts/5XcIY3ui0EQ a 1956 Chevy !  We had one like that when I was a kid.  No fender skirts in the back though but two-tone red and white.  But I remember heat in relation to the Chevy: the Naugahyde seats which would become insanely hot in the summer - also the tube radio which took forever to warm up.  But unlike the Pike's Peak climber in that ad. our 56 Chevy was a 6 cylinder  which had a hard time maintaining speed on trips to the Kettle Moraine area of Wisconsin :)  Also, as I recall there weren't any liners in the wheel wells below the fins in the back or the headlights in the front so the sand and gravel and salt from the roads would pack in and eventually rust those four areas first.  It was a nice looking car but the '56 is the middle child of those classic Chevrolets of the 50s with the 1957 being the one that everyone likes. But remembering that car from the 1950s reminded me of this video: source:  https://www.y

Whenever I open the Youtube page and see something like this: source: https://www.youtube.com/watch?v=ULPaCZMfLj4 I know that it's time to search for an obit: https://www.hollywoodreporter.com/tv/tv-news/bob-newhart-dead-sitcom-legend-1235952438/ I loved watching the various Newhart shows on TV.  I particularly remember the episode where Bob and Emily go to their neighbor, Howard's apartment (Howard is an airline pilot?) - Howard wheels out an airline drink cart with 9 zillion little bottles of liquor :)  I think the genius of Bob Newhart (and people like Jack Benny or Andy Griffith before him) was that he wasn't afraid to let other characters on the show get the laughs. And of course Bob was friends with Don Rickles, amazing: source: https://www.youtube.com/watch?v=o3cs7PyXPsU Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm