A Modern Mechanical Television -- Nipkow Discs and Arduinos Lead to a Mechanical Color TV (video)

I had, of course, heard about the mechanical TV systems that pre-dated the CRT-based "electronic TV" invented by Philo Farnsworth.  But I never really understood how they worked until I saw this Hack-A-Day article by Jenny List.  And wow, I see it now.  Nipkow discs.   Color TV.  Parts made in a 3D printer. Excellent. 

Here is Jenny's post:  https://hackaday.com/2022/05/27/3d-print-a-colour-tv/

Here's the IEEE Spectrum article by Markus Mierse (the brilliant fellow who built this amazing device): https://spectrum.ieee.org/mechanical-tv

Be sure to watch the video (above).  Take a look at the awesome quality of the 32 line color TV picture. And check out Marcus's amazingly beautiful construction.  (Note:  Built on a wooden base). 

Marcus Mierse's Modern Mechanical Color TV

"Experimental Methods in RF Design" LADPAC Software Available FREE!

We've frequently said that is pays to check the W7ZOI web site.  Tony G4WIF did just that and pointed us in that direction, noting that the LADPAC "Ladder Package" software is now available for download from that site. 

Homebrewers will really want to have that package on their computers.  There are all kinds of useful programs in that package:  software for designing crystal filters and feedback amplifiers, a program that allows you to think systematically about receiver gain distribution and dynamic range, and many other useful things.  

You can get the program here: 

http://w7zoi.net/emerrata.html

Also on Wes's site is this May 22, 2022 picture of Farhan VU2ESE with EMRFD co-author Bob Larkin, W7PUA. 

Thanks Wes! 

"Hobby High" from the Lamarkaan Radio Club and The Hindu magazine

 

https://www.thehindu.com/opinion/open-page/hobby-high/article65375392.ece?fbclid=IwAR01JGwweZuJEH1Pg15rREybZqfqKUjU3ZLbGn-xhOYZVlFPs7yN_FbJoX4

This is a really nice look at hobbies and their role in life. It is very relevant to discussions of The Knack. 

Many of the quotes resonate with me, especially those about how hobbies -- in our case ham radio -- provide an important source of enthusiasm.  I remember an old timer in Rome telling me that at age 85, he jumped out of bed each morning, heading to the radio shack with enthusiasm. 

I'd add that ham radio adds elements of permanence and continuity in our lives. For many of us, we've been working on radios since our early teens.  I have in my shack gear that I've had for almost 50 years! Amidst the vicissitudes of life, it is really nice to have things with this kind of permanence. 

Thanks to Atanu Dasgupta of the Lamakaan Amateur Radio Club of Hyderabad for alerting me to this article.  OM Atanu wrote: 

My friends, acquaintances and members from my extended family often ask me how I spend my time and keep myself busy throughout the day. When I say I pursue a hobby called Amateur Radio (Ham Radio) and I spend more than 8-10 hours in a day for that purpose, I don’t find many takers. Many of them feel that I must be earning handsomely by devoting my energy and time as seriously as pursuing a regular work-from-home regime for some corporate entity. Sometimes even my domestic help express doubts, albeit in a decent manner, about my devotion to something in life without any financial gain and expect a wage-hike for them against my ‘extra earning’. After all how can a hobby (pastime) can keep someone so engrossed physically, mentally - on the computer, over thick books/ magazines , on the work table at the radio shack, on the floor for some odd metal works, on the rooftop with antennas, over the Radio-on-air, over phone etc - without some pecuniary benefits? Recently a brilliant essay by Himani Datar on ‘hobby’ in the Hindu Magazine (https://www.thehindu.com/.../hobby-high/article65375392.ece ) has been very impressive and appears to be a savior to all concerned like me. The essay brings out all in favour of all hobbies and hobbyists and I feel more confident now about my course of engagement on a long-term basis.   

Atanu's Shack

Marohu: The Dominican Telescope with a 25 inch Mirror Originally Made for JPL

 

https://dominicanrepubliclive.com/development/dominicans-built-the-largest-telescope-in-the-region/?utm_source=rss&utm_medium=rss&utm_campaign=dominicans-built-the-largest-telescope-in-the-region

HF Bandsweep with the Hammarlund HQ-100 (video)

It has been a while since we last did a bandsweep.  Too long.  Here is one using my recently fixed up Hammarlund HQ-100.  Repair details are in recent videos. 

For this bandsweep we cover most of the HF band and even briefly dip down into the AM broadcast band: 

Demonstration of the Hammarlund HQ-100: Radio Marti, 40 meter AM, 40 Meter SSB, 40 meter FT-8, 40 meter CW with and without the Q multiplier, classical music on WRMI, WFAX 1220 kHz AM, WWV 20 MHz, CB!, 17 meter SSB, the 20 meter BS position, the effect of AVC and the Noise Limiter, SSB with the internal BFO and with the Q multiplier as BFO. CW with the internal BFO AND the Q multiplier. 

Be sure to subscribe to the YouTube channel.  

Sticker Shock -- WYKSYCDS Stickers Spotted in NYC and in a Netherlands Pub! Awards!

 

I am awarding the coveted Brass Figlagee with Bronze Oak Leaf Palm to Dave W2DAB, to Lex PH2LB, to Jesse N5JHH, and of course to Pete Juliano, N6QW.  More awards are possible.  http://www.flicklives.com/index.php?pg=215&recno=2590 

Repairing the Sony ICF SW1 Receiver -- Used for Numbers Station Reception? Why no replacement for C-625?

Ten years ago, my friend John gave me this tiny Sony receiver.  It wasn't working.   I tried to fix it but quickly discovered that the tiny size of the device made repair difficult.  All you needed to do was to swap out some leaking electrolytics, but they are surface mount electrolytics -- replacing them is not for the faint of heart.  Kits are available, but again, this is not easy. 

In 2020 I got one of the kits, but didn't try to use it until yesterday.   It only supplied six of the electrolytics.  In the video above, they discuss replacing seven electrolytics, including the one that seems to be placed in the round black holder. C-625.  Why didn't my kit include a replacement for that one?  Could it be that this capacitor was not one of the leaky SMD caps?  

Replacing these caps really wasn't easy. At one point I inadvertently removed not just the bad cap, but also a nearby surface mount resistor.  Luckily the schematic showed it to be 0 ohms.  That was easily replaced.  I lifted one of the pads on one of the other caps -- I just slid it back into place and hoped for the best. 

BTW, I just today discovered that this little receiver may have been used late in the Cold War by those who needed to receive messages from the infamous Numbers Stations: 

 https://www.cryptomuseum.com/spy/sony/icfsw1/index.htm

500 WYKSYCDS IBEW Stickers Arrive in Europe! Order yours today! Free!

Lex PH2LB in the Netherlands has gone the extra kilometer for the IBEW.  When he saw the stickers that had been placed in New York City, he asked for the design.  I sent him the files that  Jesse N5JHH (designer of the stickers) had sent to me.  Very quickly, Lex had 500 of these stickers printed up and ready to go (see above).  His shack now serves as a veritable beachhead in Europe for the IBEW and the CBLA.  Thank you Les!   

Les has even set up an on-line order form for those who seek to assist in the noble campaign to spread the word about our cause: 

https://ph2lb.nl/webshop/sticker.php

Les is making the stickers available for free -- all you need to do is pay the postage. 

Please be sure to send us pictures of the stickers after they have been placed. 

And let's not forget that the quote on the sticker is from Pete Juliano, N6QW. 

Here is one that recently showed up in Blacksburg, Virginia (zoom in on the green utility box): 

And here is Lex's very interesting site, with his Knack Story:  https://www.ph2lb.nl/blog/index.php?page=history

Frank Jones's Homebrew Rig -- as described by Michael Hopkins AB5L (SK)

"Frank is all homebrew. His receiver is unshielded outside, but built around a central square of aluminum that houses a Velvet Vernier dial thru the front panel and some tubes I did not recognize jutting horizontally on both sides of the box where coils also plug in. The transmitter is a multi-stage affair on a piece of particle board. The tubes are vertical here, and the bench was littered with brown Hammarlund coils labeled 5, 10, 20, and 80."   

https://soldersmoke.blogspot.com/2021/07/summer-reading-for-homebrewers-frank.html

https://qsl.net/ve7sl/jones%20oscillator.html

W1VD's Boatanchor Receiver Tests

I've been trying to get more rigorous in my evaluation of receiver performance.   My HQ-100 is tuned to Radio Marti, and it sounds great.  But how great is it really?  And what about all the receivers and transceivers I have built?  How good are they?  

Our friend Dean KK4DAS is about to start the rehabilitation of his dad's old HQ-170A.   A search for that receiver led me to Jay Rusgrove's very interesting measurement and analysis of old tube type radios.  Jay's results appear in the links below.  More important is his very clear description of how the tests were done and what the results mean (link below). Also included is one link showing a discussion of Jay's work.  

Jay notes: 

The decision of which boat anchor receiver(s) to own is seldom based on performance alone. A combination of favored manufacturer, period of manufacture, features, collectability or even just 'looks' often rank higher on the priority list than receiver performance. Even if one were interested in performance specs much of the available information is subjective as few receivers manufactured prior to the mid 70s have undergone standardized testing. Hard data on minimum discernable signal (MDS), blocking and two-tone IMD dynamic range is interesting to some operators and important in an historical context as it shows the progression of receiver development.

Jay designed the very first real transmitter that I homebrewed (The VXO 6 Watter from QRP Classics). Jay has been mentioned many times in the SolderSmoke podcast and blog:    

Jay's results:   http://www.w1vd.com/BAreceivertest.html

Jay's methods:  http://www.w1vd.com/Receivermeasurementbasics.html

Discussion: https://www.antiqueradios.com/forums/viewtopic.php?t=96872

Troubleshooting and Fixing Old Faults in my Long-Suffering Hammarlund HQ-100 (Part 2) (video)

Work continues on my old Hammarlund HQ-100. I give background on the rig and explain the electrical trauma it likely suffered. Following Dave K8WPE's dictum that we can still learn a lot from old receivers, I dug into this one. I wanted to fix a long-standing S-Meter/AVC problem. This led me to an interesting troubleshoot, with at least one "waste of time" detour. Eventually I found the fault in one of the coils in the grid circuit of the RF amplifier. The coils had been smoked years ago, perhaps by a lightning strike. I came perilously close to permanently losing 10-30 MHz. But I figured out how to fix the smoked coil. So my S-Meter/AVC problem was fixed. I really like listening to this thing. There is still a lot of nice material on the SW bands. There are some very nice broadcasts in Spanish. Please subscribe to my YouTube channel.

You can see where the coil burned. Wire remained intact, but the insulation burned creating a Primary to Secondary connection.

I just very carefully lifted one of the coils way from the other, eliminating the unwanted connection.

Here's my homebrew "RC Printed Network" Z2 module. This was unnecessary -- the original was good. I put the original back in.

Electric Radio magazine recently ran a two part series on the HQ-100. I have ordered these issues of the magazine.

Tim Hunkin on Prototyping, Welding, and on Being a "Jack of all Trades"

I always like Tim Hunkin's videos, even when they are not directly related to radio electronics.  In this one we learn about his prototyping techniques -- this does seem similar to what many of us do when building rigs.  

I liked his explanation of welding, and of the dangers of the angle grinder (his precautions on this device were similar to those in a recent video by "Spirited Man" Van Neistat). 

Tim's final comment on how in the modern world we seem to have moved away from the notion of having one person skilled in many different areas -- we are now very specialized, so the "Jack of All Trades" is increasingly rare.   That's a shame.  Oh well, we can be Jacks of all Trades in our radio shacks. 

Thanks Tim!