A Crummy Commercial

 Mentioned previously here: https://wb9kzy.blogspot.com/2023/02/the-holmdel-horn.html I know that many don't read the ARRL letter but this weeks had good news about the antenna: http://www.arrl.org/arrlletter?&issue=2023-06-29 Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

 No contest, email is FAST but USPS is actually more reliable.  Latest case was a customer where I wanted to contact him prior to sending his order to clarify what he wanted.  I sent several emails and then several days later he seemed to answer my question and asked if I got his mail order but they were not direct replies, a couple of new emails. Then I send the order and also send an email with tracking info, no response on the tracking info but that's often the case. The kit arrives and the customer has an email question about it, I reply within the hour.  But the next day I get the same question.  BTW, these are all to/from my gmail account. It finally dawned on me that he hadn't been getting my emails.  So I switched to my hotmail account and boom, got right through. If you are a customer please know that I try to reply quickly, if you didn't hear back from me, check the email bit bucket, spam folder or whatever it's called, my reply is probably in the...

I thought this was an amazing photo from NASA, June 26, 2023: source: https://earthobservatory.nasa.gov/images/151507/canadian-smoke-reaches-europe Looks like Spain and Portugal are pretty arid but if they get any rain soon it will probably be smoky water !  I guess that's not strictly true since the smoke in the picture is above the clouds ? There was also this picture from June 16, 2023 of the smoke over the Midwest: source: https://earthobservatory.nasa.gov/images/151468/smoke-blankets-the-upper-midwest I have a poor sense of smell but that smoke smell is strong here outside and even inside. If I go riding my bike I think I'll put on the N95 mask first but maybe this is a good excuse to not strain myself :) Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

 These videos were mentioned on the Soldersmoke blog: part1 source: https://youtu.be/B-4cUGSsGPQ . part 2 source: https://youtu.be/mgi34ogzbvY   part4 source: https://www.youtube.com/watch?v=01GzduUaLOE Several things of note: 1) reading the state of neon lamps with photo sensitive resistors ?  WOW The photo resistors reminded me of how an HP ink jet printer head looks. 2) Step recovery diodes to generate a 100 ps blip every 100 ns (10 MHz rate) for the comb generator.  double WOW The narrow blip results in only a 2 db spread of harmonic amplitude !  If only the SRDs were cheap, they could be used in a crystal calibrator ! 3) the cavity tuned LC filter to select individual harmonics in the range 10-500 MHz (or higher) from the comb generator ?  triple WOW   Silver plating, fancy glass discs but ultimately done in by grease seizing up the gear train.  This reminded me of the infamous Ten-Tec PTO grease problems.  Something about grease wa...

 I still haven't tried the W2IMB active antenna: https://wb9kzy.blogspot.com/2023/06/simple-active-antenna.html  but this one is even simpler by virtue of using only 1 transistor: although the coupler circuit is more complex and a toroid is used (note that the transistor is a J310, J301 is a typo).  It's from a series of articles by R.W. Burhans in the February to June 1983 issues of Radio Electonics magazine.  The schematic was on page 64 of this one: https://archive.org/details/radio_electronics_1983-03/page/n63/mode/2up This issue is also available on the wonderful yet wacky World Radio History site: https://worldradiohistory.com/Radio_Electronics%20_Master_Page.htm R.W. Burhans was a prolific author in this area, here is another more complex earlier design in a NASA publication: https://ntrs.nasa.gov/api/citations/19790011925/downloads/19790011925.pdf and this one: https://ntrs.nasa.gov/api/citations/19750020206/downloads/19750020206.pdf I believe I may have most...

 Not actual animals but some cat sculptures in the chimney of a house in Fox Point, WI.  I remember being in the back seat of the car as a kid coming home from a shopping trip, Dad would always go down Lake Drive and I'd look for this house with the cats, here it is courtesy of the internet in  2009: Not sure why there is a double image, but those items in the chimney are cats. And again in 2011: Yet another time in 2015: But in 2021 they were gone !   What happened to the cats ?   Another possible mystery for a 21st century version of the Hardy Boys ? This house is on the east side of Lake Drive across from a narrow parkway behind the railroad tracks and then the Village of Fox Point municipal buildings. It is kinda fun to periodically take a virtual stroll or drive around places I used to know well. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm             

 I found an article for a simple active antenna in the February 1989 issue of Monitoring Times, pages 96 and 97:   https://worldradiohistory.com/Archive-Monitoring-TImes/1980s/Monitoring-Times-1989-02.pdf The article is by Ken Cornell, W2IMB, known for the book: The Low and Medium Frequency Radio Scrapbook. The idea is to get the antenna out of the house away from all the sources of buzzing and interference.  The thing I like about this design is that it's simple and the parts are still fairly easy to get: Since this is a receive only antenna, power can be supplied to the remote amplifier via a simple circuit rather than some exotic Bias-T circuit: There are popular active antenna designs from PA0RDT and PA3FWM on the internet but these employ more exotic parts, use more power and just seem fussy.  I'm sure they perform well but I'm not keen on trying them. http://dl1dbc.net/SAQ/Mwhip/Article_pa0rdt-Mini-Whip_English.pdf http://www.pa3fwm.nl/projects/miniwhip/ I will...

 I got this email announcement on Thursday, June 22, 2023: It's a shame but I have to confess that I haven't bought anything from All Electronics in a long time.  They have interesting stuff but lately much less actual surplus. Now Electronic Goldmine seems to still have a lot of new surplus stuff coming in.  And they actively flog it everyday with emails.  And their niche items are the Geiger tubes and counters.  However I haven't bought from them since their credit card processor fiasco. All Electronics seemed to have lost their ability to attract with novelty the way Electronic Goldmine does.  All Electronics would send one email a week with a lot of stuff that could be found on ebay. If bad things come in threes then hopefully this is the last one joining BG Micro and Dans. https://wb9kzy.blogspot.com/2022/05/another-one-bit-dust-year-ago.html https://wb9kzy.blogspot.com/2022/08/another-parts-supplier-calls-it-quits.html But then I saw this: So one doo...

 After messing with the Audio Clipper: https://wb9kzy.blogspot.com/2023/06/simple-audio-clipper.html I continued looking at the old QST articles (searching on "limiter")  until I found this one from December 1966 QST: html version: https://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/qst/1966/12/page22/index.html In this article W9NLT presents the idea of using semiconductor diodes to automagically switch in attenuator sections: Here was his schematic for a buildable circuit: . As with the clipper I'd sub the BAT42 for those now unobtanium 1n34s. Essentially the clipper was modified by adding another resistor and then cascading sections to kerchunk in attenuation as the signal increases.  Unlike the clipper the  attenuator doesn't add as much distortion. I tried this directly from the rig audio but the results were unseen unless the volume was raised to concert hall levels.  So keeping in mind that W9NLT was working with 600 ohm tube gear, I ...

Update: 6-22-2023 PM  I got this email from the NY Times: (at least I got diverted back to those Dobie Gillis episodes due to this incident) ---------------------------------------------------------------------------- At least they are hearing periodic banging ?  https://arstechnica.com/gaming/2023/06/submarine-missing-near-titanic-used-a-30-logitech-gamepad-for-steering/ David Pogue's CBS Sunday Morning report from November 27, 2022:  https://youtu.be/29co_Hksk6o Tuesday morning report on CBS: https://www.cbsnews.com/news/what-happened-to-missing-titanic-submarine-david-pogue-oceangate-possible-scenarios/#text22The20deepest20submarine20rescue20ever20performed20was2012C500weeks20to20prepare20and20are20not20on20site BTW, one thing that irritated my Dad about Jane Pauley was the way she would wrinkle her nose (which I never noticed).   But I still remember the running gag on the Dobie Gillis  program where Zelda would wrinkle her nose and Dobie couldn't help but ...

I've seen the dual diode audio clipper circuits in many a QST and other publications but never tried it before now.  I saw this circuit in a Hint and Kink from February 1966 QST page 70: The only change I made was to use BAT42 Schottky diodes.  This results in a clipping level of about 400 mV peak to peak as shown here (WWV on 10 MHz): The idea is to protect your ears when using a receiver without AGC.  The limiting action is fast: Unlike an add-on audio AGC where there is often overshoot present for the initial cycles.  With RF AGC overshoot is less of a problem. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

 This is an interesting article in the general interest magazine, Harper's, from October 1941. The article was mentioned in the November 1941 QST: Two items in particular caught my eye: 1) Judy Garland was a ham radio operator ?  That's amazing.  Hoover I knew about but not Garland.  Her name originally was Frances Gumm so it might be possible to find her in a callbook ?  I looked in the Fall 1940 Callbook in area 6 but didn't find anything under Gumm or Garland. 2) The story of the FL hams who go to visit a fellow net participant is very memorable: . . The article also mentions the then ongoing war and that ham radio would change when the USA enters the war. Volume 183 of Harper's can be found here on archive.org: https://archive.org/details/harpersmagazine183junalde/page/534/mode/2up The article starts on page 535.  A pdf can be downloaded. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm  

 I breadboarded the Super Whoopee circuit although I left off the 3 audio amplifier transistors and the speaker.  I wasn't able to find my 2n107 so I used a 2n241 instead.  Here is the magazine schematic again: Here is the breadboard: I then connected the output to an LM380 audio amp.  I used 3 switches of a DIP switch for S4, S5 and S6 instead of using mercury switches.  Then I took pictures and captured sound for each of the 8 combinations of the three switches: It isn't as much fun as I remember.  Of course that was more than 50 years ago now :)  Anyway, don't think I'll pursue the Super Whoopee idea any further, at least as it was.  Although maybe if I get one of those TI sound chips ?  We'll see. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

I thought this was neat: https://www.microsoft.com/en-us/edge/features/pdf-reader-at-work?form=MT00D8 I usually use Firefox but often use Edge with Bing.  This will be handy for editing pdf files such as the kit order form: http://wb9kzy.com/jhphamor.htm Here is a screenshot of my attempt at editing: Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

Also found in the junkbox with the other unijunction transistors yesterday were 10 x 2n6028 PUT transistors from Digikey.  These are similar to regular unijunctions like used in the Super Whoopee but they must be "programmed" with two resistors as seen in this circuit from the ON Semiconductor datasheet page 4: So I tried one of the 2n6028 PUTs in the same circuit as yesterday, except added two resistors, a 5.1k ohm for R1 and a 4.7k ohm for R2, this was the result: So the PUT is similar to the other "real" unijunctions.  However like the "real" unijunction transistors the 2n6027/28 PUTs are only available on the secondary market, ON Semi has discontinued them. But it is nice to have choices, especially if they are cheaper. Best Regards, Chuck, WB9KZY http://wb9kzy.com/ham.htm

 I did a little on trying to simulate unijunction transistors like the 2n2160 used in the Super Whoopee circuit (shown here): See the original post for links to the complete article: https://wb9kzy.blogspot.com/2023/04/the-high-school-club.html But no luck getting any output in LTspice, it must be the initial conditions, probably some kind of noise or transient is needed to kickstart the simulation.  I'll try it again some other time. Back to the Super Whoopee, it took a while but I found my unijunction transistors, the 2n2160 (2), a HEP310 and a 2n2646.  I then tried them in the leftmost part of the Super Whoopee circuit and got these outputs: 2n2160 with 4.7 uF, 150k ohms, 9V supply HEP310 with 4.7 uF, 150k ohms, 9V supply 2n2646 with 4.7 uF, 150k ohms, 9 V supply Basically all are sawtooth waves although they differ in period and amplitude.  Looking at the Super Whoopee circuit there are two of these sawtooth oscillators, on the left is a slow one with a period of...