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Saturday, April 3, 2021

A VERY Successful April Fools' Day

 
I was worried.  It was early on the morning of April 1, 2021, and I had NOTHING. Maybe this  was because so much unbelievable stuff has recently happened in the world.  Or maybe it is because technology has been moving so fast that today's April Fools' joke is tomorrow's new device. Whatever the reason, for the first time in about 15 years, I had noting.  April Fools' Day has long been part of ham radio's culture and I was worried that I would not be making a contribution this year. 

Then something caught my eye.  Did you know that on Thursday they decided to change the rules of chess!  Yes indeed!  NO MORE DRAWS!   Fantastic!    This provided the inspiration for our announcement of the brutal FCC rule-making action regarding the banning of "legacy equipment."  

I knew that that headline would attract a lot of attention. And let me inform you that, according to the official rules of April Fools' Day,  if that headline did pull you in,  well that constitutes a "gotcha."  So far 1,758 people are in this category.  I thank you all.   

The comments attached to the announcement were really heart warming, even those that included profanity directed at my persona.  People recalled earlier April 1 events, like the time Pete was defenestrated from the QRP Hall of Fame.  Good times, my friends, good times!   

This was an especially happy April 1 for me, because I also launched two other highly successful operations: 

-- I teach a Zoom class.  On Thursday morning I told the students about new concerns regarding  the light hitting their eyes from the computer screens.  We were all being issued dark glasses and would henceforth have to Zoom with shades on (see above).  The students -- bless their hearts -- all agreed to do this.  

-- We are closely associated with a small company that has the word "native" in the corporate name.  As in "Native Vegetation."  Shockingly, last Thursday we got an e-mail from the Virginia Small Business Commission DEMANDING that we change the name of the company.  It seems that ANY use of the word "native" was now deemed unacceptable.  The people in this company (ALL OF THEM!) were really outraged by this.  I had to pull the plug before any legal actions were initiated!  

So, to all of you, Happy April Fools' Day!     

Thursday, April 1, 2021

FCC to Ban "Legacy" Equipment and Circuitry


From the FCC Newsline: 

Out with the old

In a long-expected policy move, the Federal Communications Commission today announced that starting on April 2, 2022,  all equipment in use by the amateur radio service must comply with strict emission purity standards.  The Commission's rule-making focuses on the bandwidth of high frequency transceivers.   Starting one year from tomorrow,  amateur equipment will be limited to a bandwidth of 3500 cycles per second.   Emissions outside the bandwidth limits must be at least 100 db below the average power in the bandpass.  In effect, this means that amateur equipment must make use of the kind of "brick wall"  filtering only available from software defined equipment.   Bringing the service into conformity with commercial practices, all high frequency equipment will be on Upper Sideband.  

"No more skirts" 

An FCC official -- who requested anonymity because of "threats"  -- told Newsline that part of the motivation behind today's announcement was a desire to end the unseemly discussion of the filter "skirts" of "legacy" ham radio gear:  "Obviously there were concerns about the pejorative way many hams were referring to 'the skirts.'  This is the 21st century!  It was time to be more inclusive!" 

Audio Tinkering to Continue

The FCC official told Newsline that the Commission is not in any way attempting to discourage hams from tinkering with the "audio quality" of their commercial SDR equipment: "As long as they keep the bandwidth to 3500 Hz, they can tinker and adjust to their hearts' content," said the official.  He went on to use some of the colorful language recently heard on the ham bands: "If they want to include very low audio frequencies -- what some call 'the thunder down under' they can do that.  Or if they want to emphasize the high frequencies -- for that "Krispy Kreme" sound -- they can do that too.   All they have to do is learn how to set  the menus on their equipment. We understand that the manufacturers will soon be making available software packages that will -- with just a simple download -- set the menus according to the desires of the consumer. Uh,  I mean of the radio amateur." 

The FCC official said he thinks the ruling will actually encourage and facilitate audio tweaking. "We know this is important to modern hams.  It makes them feel connected to the days when hams actually built their own equipment.  We have noticed the development of an amazingly rich  technical vocabulary, terms like 'presence'  "muddy'  'bright'  and 'punchy' are now in common use.  Clearly the Commission would not want to stand in the way of this kind of technical advancement!"

Sinking the Boatanchors

The FCC acknowledged that this ruling spells the end for on-the-air use of  older ham equipment. "Clearly none of that old junk will meet the new requirements.  I mean these guys were literally using hunks of rock to filter their sidebands.  It was practically medieval!  Time to wake up, smell the decaffeinated coffee, and get with the SDR program OM!" 

Fears of violent push-back

The FCC official did acknowledge that there are fears of possible violent push-back from certain "sub-cultures" in the ham radio world.  "Working closely with our partners in Homeland Security, we have looked closely at the possibility of violent pushback.  Of particular concern are groups that appear to be fiercely loyal to what they sometimes defiantly refer to as 'Hardware Defined Radio.'   There are some truly frightening groups out there.  One group is called the CBLA -- The Color Burst Liberation Army.   They seem especially fond of quartz crystals and are radically opposed to the new SDR requirements.  Also of concern are groups that continue to insist on using Double Sideband Unsuppressed Phone generated by equipment using vacuum tube.  Vacuum tubes! They call them 'thermatrons.'  Again this is really medieval."  The spokesman said that the FBI is monitoring these groups, but is not very concerned because of the physical condition of many of the fanatics.  "Most of these guys rarely leave their homes.  In fact, for the last year many of them seem to have been repeating a strange "Stay in the Shack" mantra.  Many still smoke, never exercise, and now refuse to take the vaccine.  So we are not too worried, " said the FBI spokesman. 

Support from Industry and the Major Ham Organization

FCC officials tell Newsline that the major equipment manufacturers -- along with the principal ham radio organization -- were very supportive of this move, seeing it as a major opportunity to "stimulate" both sales and advertising revenue. 

Wednesday, March 31, 2021

Mending vs. Ending -- The Fight Against Planned Obsolescence


We don't get a lot of mail from Darwin, Australia, so the message coming in from Phil VK8MC immediately got our attention.  When I looked into the details I realized that it was very SolderSmoke-relevant.  The Guardian article that Phil cited even mentions hobbyists tinkering with electronic devices in their sheds (that would be us!).    Phil points to the connection between our repair efforts and the struggle to save the planet: "It's not just a hobby, it's an ethical position which contributes to the well being of the planet. A higher calling indeed!" 

Here is the article Phil pointed us to:

https://www.theguardian.com/commentisfree/2021/mar/17/ending-over-mending-planned-obsolescence-is-killing-the-planet?CMP=Share_AndroidApp_ProtonMail

The poster above (which hangs above my workbench) is from https://www.ifixit.com/Manifesto


Monday, March 29, 2021

"Analog Man in a Digital World" by OM Joe Walsh (music video)


After seeing my last post about SDR, the dongle, the Android tablet, and the Bluetooth mouse, Bob Keller grew concerned about my, uh, stability.  Here is our e-mail exchange. 

Bill, 

Have you had a comprehensive medical evaluation recently? All this digital activity from an erstwhile analog man is a concerning symptom. <g>

I suggest listening to the following number at least once each day until you have the chance to get checked out:



-- 73 de KY3R, 
    Bob Keller


Bob: 

I know.  It really is quite disturbing.  I've been getting a lot of "welcome to the dark side" messages!!!  

I am now trying to get back in the good graces of The Radio Gods.   Today I fired up the Fish Soup 10 and made two CW SKCC contacts on 40 meters.  I feel better already.  

Thanks for the song from OM Walsh.  I had heard it before but it is more meaningful to me now.  I will put it on the blog.  Others may need help too.  

Thanks for caring Bob.  

73  

Bill 

Tuesday, March 23, 2021

Double Sideband Transmitter using Vacuum Tubes -- From Sweden


Tommy SA2CLC has built a really nice DSB transmitter using Thermatrons.  
FB Tommy.  

Monday, March 22, 2021

My Hodgepodged Morse: Audio Tone into the Mic Jack Creates J2A not A1A. BASTA!


In SolderSmoke podcast #229 Pete and I were discussing my rather flaky effort to turn the Hodgepodge BITX40 Module into a CW rig by injecting keyed 700 Hz audio into the mic jack (see video below). We got some very helpful responses from ND6T and VK2EMU:  


Hi Bill,

You mentioned generating CW by modulating SSB: Collins did that in their
first SSB transceivers, I believe, as did SGC, but the results were less
than optimal. The problem is that you are involving the audio chain and
modulator. You know from experience how difficult it is to maintain low
intermod there and the tone is no exception. So we end up with lots of
spurs within the filter passband and then also have the opposite
sideband suppression less than perfect. If you check your transmitted
signal with a spectrum analyzer or SDR you can easily see the nasties.
Listening to a CW signal thus generated makes it obvious unless it is
buried way down in the noise. It IS a valid CW signal (not MCW) since it
is (almost) a single signal. However, in actual operation it doesn't
work very well.

I know because I have done that. I bought one of Farhan's original
BITX40 boards and wanted to put it on CW. I ended up injecting a keyed
signal from one of the spare clocks on the Si5351 into the RF amplifier
chain (thus avoiding the above stated problems) but still had garbage
from the audio and IF stages. I fixed that by shorting out that signal
during transmit by a transistor to ground. That was documented on your
BITXhacks website: http://bitxhacks.blogspot.com/2017/02/ and on my
website: http://www.nd6t.com/bitx/CW.htm . It has been a while, eh?

...

Don, ND6T

--------------------------------------------------

Hi Bill and Pete,


With putting an audio oscillator into you hodgepodge radio, your transmission is not the same as a standard CW rig.


If we have a transmitter as described in the ARRL handbooks from the 1940's or 1950's, (or even the Michigan Mighty Mite) it is a crystal oscillator and maybe a PA tube. By keying either the oscillator and/or the final PA on and off, then we can send Morse code as ICW Interrupted Continues Wave. If we check the list of emission designators, we have A1A.


However, if we feed a tone into a SSB transmitter, then we have J2A.


At the other end it may sound the same, but because it is created in a different way, it has a different designation. 


A quick look at Part 97 shows that J2A and J2B are classed as CW, so you are in the clear. However, if you put a tone oscillator into an AM signal to send CW, then that would be classed as A2A and not classed as CW, but as MCW. MCW can be used on 6 meters and above, but not HF.


SITS.


73 de Peter VK2EMU

-----------------------------------------------------------




So I say BASTA with the J2A!  If I want to go CW, it's all A1A for me.  I dusted off my Fish Soup 10 and am now back on 40 CW with 200 mW.... A1A all the way! 

 

Saturday, March 20, 2021

SolderSmoke Podcast #229 -- G2NJ Trophy, SDR, HDR, CW! Mailbag


Soldersmoke Podcast #229 is available: 

http://soldersmoke.com/soldersmoke229.mp3


--  G2NJ Trophy is awarded to Pete Juliano, N6QW. 

 -- Get your vaccine shot as soon as you can!  

-- More from "Conquering the Electron" by Derek Cheung. 

-- Bad fire in the chip factory.  Such a shame.  Sad!  I had NOTHING to do with it.  I was home that day.  I can prove it.

 -- Bezos is not such a bad guy.  Turns out he is a space-geek.  

 -- Perseverance was the big space news.  Very cool.  

 

Pete's bench:

Raspberry Pi vs. Microcontrollers

Treedix display

Conversion of the Dentron Scout

CW rigs?

6L6 on a wooden chassis


SHAMELESS COMMERCE DIVISION-  

I NEED TO BUILD UP TIME VIEWERS VIEW MY VIDEOS: So please watch!

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--  Our Patreon sponsors get an early look at our YouTube content.  So please, consider

becoming a Patreon sponsor.

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Bill's bench: 

Hodgepodge:   

-- BITX40 Module.  

-- Ramseykit Amp. 

-- San Jian counter,  

-- CW using 750 Hz oscillator. 

-- RF-actuated piezo buzzer.  

-- SDR!  SDR using PC and tablet.  

-- Checking the output with SDR.  

-- Moving the carrier osc frequency.  

 Also, I put the Fish Soup 10 back on the air.  Nice contacts under 200 mw.

Up next:  A rig for 80/75 and 20 meters.  Single Conversion.  Using VFO from a Yaesu FT101 that runs 8.7 – 9.2 Mhz.   Quiz question:  What IF should I use?

MAILBAG

Mark Zelesky sent me wood tokens with power and Ohm's law formulae.  Thanks!

Scott WA9WFA Built a really nice Mate for Mighty Midget RX – getting it going!

Tryg EI7CLB found board of his George Dobbs Ladybird RX.  Rebuild it OM!

Tom WX2J – We talked about “No lids, no kids, no space cadets” nastiness.

Nick M0NTV about sideband inversion.  I like the simple rule about subtraction.

Jonathan M0JGH – Always listen to Pete.  Got married, has mixing product. Leo?

Mike AE0IH.  Dad used a BC-348 in the service. Looking for one.  FB.

Adam N0ZIB – “Silent Shep” site --- with some ham radio shows I had not seen.

Walter KA4KXX in Orlando has a similar subtraction problem with San Jian counter.

Bill N5ALO sent me a really nice KLH speaker.   I’m using it now.

Jason N2NLY – interested in building SSB transceiver.  One step at a time OM…

Trevor in Annapolis sent xcsd cartoon that really hit home. 

Farhan is doing OK in India, diligently protecting his family from the virus.  

Peter VK2EMU also doing well.

Dave AA7EE Casually killed a DC receiver in Hollywood, and disposed of the remains. 

Charlie ZL2CTM doing great things with simple SSB.  Blogpost.

Phil VK8MC in Darwin sends article on "Mend not End" battle against planned obsolescence.

Bob KY3R re my SDR adventures, asked if I’ve had a recent medical/psychiatric evaluation. 


Friday, March 19, 2021

Hodgepodge: Tablet SDR with a Bluetooth Mouse (video)


I continue to find things in the shack that I can connect to the Hodgepodge.  Here it's an old Android tablet with a Bluetooth mouse.   

The waterfall is pretty, but this addition just shows why SDR is really TOO easy.  The modified RTL-SDR dongle is doing direct sampling, so there is not even any phasing circuitry to tinker with.  All the filtering and sideband selection is happening in software inside the 40 buck Android tablet.  The results look nice, but I don't find it very satisfying -- all I did was connect some cables.  So it's back to HDR for me. 

Tuesday, March 16, 2021

A REALLY Cheap Receiving Rig


Wow, lots of ingenuity in this 1921 receiver.

-- Has anyone actually made a diode out of a light bulb in the way described? 

-- The antenna coupler on the table leg is not much different from the tuner that I have attached to the wall of my car port. 

-- Note that when our hero finishes the receiver, he is able to pick up signals from Mars!  FB OM. 

Who will be the first to recreate this 1921 receiver? 


Monday, March 15, 2021

Aladdin's Lamp == The Vacuum Tube (aka The Thermatron) (Video)


After our posting of the video about 1957 transistor production, our friend Peter O'Connell VK2EMU asked for some equal time for vacuum tubes.  He sent me this 1940 Western Electric video.  It is quite interesting. 

-- I like the Aladdin's lamp metaphor.  When I was out in the Azores I thought of my homebrew 17 meter DSB rig as my "magic carpet." 

-- Lowell Thomas was brought in to narrate.  His voice sounds a lot more natural than that used to narrate the transistor film. 

-- To explain the effectiveness of transcontinental telephony with vacuum tube repeaters, they compared the system that of a relay of "hog callers" claiming that it would take 100,000 hog callers to carry a signal from New York to San Francisco.  So perhaps this could be a rival to db?   100,000 hc? 

-- Arlington to Paris 1915 caught my eye -- Arlington Va. is right down the road. 

-- The film of Edison in his lab was good to see.  And note the importance of his lab notebooks. 

-- The explanation of thermionic emission was quite good.  But of course too much credit was given to Lee DeForest. 

-- The breathless description of the amazing uses of tube technology was for me a reminder of how recent this technology is.  My father started as New York City cop in the 1950s.  He always referred to his police car as a "radio car." 

Hey, are any radio amateurs out there using one of those big water-cooled tubes?  If not, why not? 

Sunday, March 14, 2021

A Homebrewer

 

That is Homer Price, the lead character in two books by Robert McCloskey, published in 1943 and 1951.  The thing in the valise is Homer's pet skunk.  Of course. 

More info here: 


Homer is clearly a fellow we need to know more about.  I have ordered the book. 

Saturday, March 13, 2021

Making Transistors in 1957


Thanks to Thomas K4SWL for alerting us to this video -- he had it on his excellent SWLing Post blog

Many things crossed my mind as I watched this video: 

-- Pocket protectors!  Pete recently noted that this was a common fashion accessory among electronic techs and engineers back in the day. 

-- HP test gear. 

-- "Extreme cleanliness" that doesn't seem quite so clean.  

-- 550 transistors per hour.  Now we have upwards of 50 billion on a single chip. 

-- The Germanium salami that Pete mentioned in our last podcast. 

-- Hints of Silicon's impending replacement of Germanium. 

-- A transistor factory in Spring City, Pa. that "hums with excitement" (seemed kind of sleepy). 

-- The 1957 assumption that Philco transistors would be in the first orbiting satellite.  Then came Sputnik.

-- The transistor that moves like a "Gulliver through Lilliputian lands."  

-- Our voices or accents seem to have changed, at least the voice used in products like this.  No one talks that way today. 

-- As I watched, I tried to remember if Pete's CK722 was made by these folks.   But no, that was a Raytheon product.   Here is a nice short description of the early days of the CK722:   https://en.wikipedia.org/wiki/CK722   We need to learn more about the hobbyist Carl Todd.

Friday, March 12, 2021

The Secret Life of LEDs -- A new Tim Hunkins Video


Thanks to Tony G4WIF for alerting us to this really nice video from the fellow who made all those great "Secret Life of Machines" videos.   This video on LED's makes me want to improve the lighting in my work shop.  And I think I need some more high wattage resistors.   I'm really glad Tim Hunkins is making more videos.  His look at the Secret Life of  Radio was a real masterpiece. 

Thursday, March 11, 2021

Hodgepodge: Moving the Carrier Oscillator Frequency (and a Flashback to 2002) (Video)

As explained in the video, in the course of using my RTL-SDR dongle I noticed that the signal being put out by my Hodgepodge rig had some problems.  There was poor opposite sideband rejection, and in terms of audio quality I has putting out too many lows and too few highs.  I figured the problem was the result of the carrier oscillator frequency being a bit too low, a bit too close to the flat portion of the crystal filter passband.   I needed to move that carrier oscillator frequency up a bit. 


BITX40 Module BFO 

In the actual BITX40 Modules, L5 was replaced by just a jumper wire, and the C103 trimmer was not on the board.  Farhan and his team instead selected X5 crystals to match the passband of the 12 MHz crystal filter. Mine was originally at 11.998653 MHz.  But I wanted to tweak mine a bit -- I wanted to move it up about 500 Hz.  Reducing the capacitance would move the frequency up. Putting capacitance in series with C102 would have the effect of reducing the capacitance in the circuit.  I just removed the jumper wire and used the holes for L5.  First I put in a single 30pf capacitor.  This dropped the capacitance between X5 and ground to 18 pf.  That resulted in too large a shift.  So I added another 30 pf cap in parallel with the first one.  This resulted in a total capacitance from X5 to ground of 26 pf.  This was about right -- the carrier oscillator/BFO frequency was now 11.9991 Mhz.  I had moved the carrier oscillator frequency up by 447 Hz -- just about what I was hoping for.  

This was a very satisfying fix.  it was a chance to put to use experience with other SSB rigs, to make use of the RTL-SDR dongle as a diagnostic tool, and to tinker with the BITX40 Module in the way that Farhan had intended for it to be tinkered with.  

I'd done this kind of adjustment before, but without the benefit of an SDR display.  Below is the story of one such adjustment. 

---------------------------------

A Flashback to 2001-2002
(From my book "SolderSmoke -- Global Adventures in Wireless Electronics")

Now it was time for some debugging and fine tuning.  I needed to make sure that the frequency of the carrier oscillator was in the right spot relative to the passband of the crystal filter.  If it was set too high, the filter would be chopping off high notes in my voice that were needed for communications clarity, and it would allow too much of what remained of the carrier (residuals from the balance modulator) through. If it was set too low, the voice signal transmitted would be lacking needed base notes.  I didn’t have the test gear needed to perform this adjustment properly, but my friend Rolf, SM4FQW, up in Sweden came to my aid.

One night, during a conversation with Rolf, I explained my problem and he offered to help me make the adjustments… by ear.  Performing an electronic version of open-heart surgery, with power on and Rolf on frequency, I opened the case of the new transmitter.  The carrier oscillator has a small capacitor that allows the frequency of the crystal to be moved slightly.  With Rolf listening carefully, I would take my screwdriver and give that little capacitor a quarter turn to the right.  “Better or worse?” I would ask. 

I think this little adjustment session captures much of the allure of ham radio.  There I was, out in the North Atlantic, late at night hunched over a transmitter that had been forged from old Swans and Heathkits, from cell phone chips, and from bits of design from distant members of the fraternity of solder smoke.  Pericles, the source of many of the key parts, was gone.  So was Frank Lee, the amateur whose SPRAT article had inspired the project.  But Rolf and I carried on with the core tradition of the radio fraternity: hams help their fellow hams overcome technical difficulties.  

Tuesday, March 9, 2021

Straight Key Night 2021 at SA2CLC in Sweden


Wow, check out the FB gear of Tommy SA2CLC in Sweden, in use on Straight Key Night 2021. There is some German WWII gear,  a BC-348,  a homebrew transmitter, and some FB QRP kits. 

More on Tommy SA2CLC here: https://www.qrz.com/db/SA2CLC 
The culvert under the road for coax to the antennas is very cool. 

FB Tommy!  A belated HNY to you OM. 

Taking Care of an Old Analog Machine -- The Scanimate


Of course, I understand and sympathize completely.  

Thanks for Rogier PA1ZZ for sending this.  

Monday, March 8, 2021

AA7EE Casually Kills a Direct Conversion Receiver, then Coldly Discards a Diode Ring Mixer

I was really glad to see that Dave AA7EE has -- after a long absence -- posted another article on his blog.   The article has some great personal reminiscences about his involvement with direct conversion receivers.  Here is one passage: 

I spent many happy hours tuning around and listening on 80M with the DSB80. It was this first experience that cemented my affinity for direct conversion receivers built with commercially available diode ring mixer packages. It just seemed so simple – you squirt RF into one port, a VFO into the other, and (after passing the result through a diplexer) amplify the heck out of the result. The seeming simplicity of the process of converting RF directly to baseband audio has held great appeal for me ever since. Unfortunately, that project didn’t survive. One day, in later adulthood, in my apartment in Hollywood, I reversed the polarity of the 12V DC supply and, discouraged at it’s subsequent refusal to work, tossed the whole thing away. Now, I cannot quite believe that I did that, but it was during a long period of inactivity on the ham bands, and complete lack of interest. If only I could go back, and not have thrown it into the dumpster of my apartment building! Hollywood is ridden with recent notable history. My little double sideband transceiver met it’s unfortunate end just 100 feet from the spot where Bobby Fuller, of The Bobby Fuller Four, was found dead in his car, in 1966, the subject of a still unsolved mystery to this day. The death of my little DSB rig was a lot less mysterious. To think that I heartlessly tossed an SBL-1 mixer into a dumpster, is a mark of how far I had strayed from my homebrewing roots, forged in a little village in England. Now, a few years later, in a city known for it’s sin and excess, I had cruelly ended the life of a stout and honest diode ring mixer. I suppose I should spare a thought for the polyvaricon but, well, you know – it was a polyvaricon!

  https://aa7ee.wordpress.com/2021/03/04/the-ve7bpo-direct-conversion-receiver-mainframe/

Sunday, March 7, 2021

EXORCISM! 40 Meter RFI Problem Resolved

BEFORE

David W. suggested I use my RTL-SDR dongle to look for the source of the 40 meter RFI that I have been mentioning.  (It appears as an ugly stipe in the waterfall of my Hodgepodge transceiver.) So I fired up the RTL-SDR -- there were the tell-tale spikes, spaced neatly every 50 kHz.  The ARRL Handbook says this is typical of a switched power supply.  Before I started patrolling the neighborhood with a tin-foil hat and a portable receiver, I decided to check my own house for any recently installed electronic devices.  It didn't take long -- when I unplugged the new (mid-pandemic) treadmill the spikes disappeared.  This treadmill was located about ten feet above my rigs, and between the rigs and the antenna.  Duh.  I should have thought of this earlier. Mystery solved.  Thanks David. 

AFTER


Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column