Three Cheers for the uBITX! Keeping problems in perspective...

This morning I was looking at Farhan's uBITX page.   He got philosophical at the end of the circuit description: 

As a fresh radio amateur in the 80s, one looked at the complex multiband radios of the day with awe. I remember seeing the Atlas 210x, the Icom 720 and Signal One radios in various friends’ shacks. It was entirely out of one’s realm to imagine building such a general coverage transceiver in the home lab.

Devices are now available readily across the globe through online stores, manufacturers are more forthcoming with their data. Most importantly, online communities like the EMRFD’s Yahoo group, the QRP LABS and BITX20’s groups.io community etc have placed the tribal knowledge within the grasp of far flung builders like I.

One knows that it was just a matter of breaking down everything into amplifiers, filters, mixers and oscillators, but that is just theory. The practice of bringing a radio to life is a perpetual ambition. The first signal that the sputters through ether, past your mess of wires into your ears and the first signal that leaps out into the space from your hand is stuff of subliminal beauty that is the rare preserve of the homebrewer alone.

So true!   Over on the BITX.io group there is a very interesting discussion of the extent to which the uBITX is in compliance with FCC and ITU specs on harmonic and spur emission. In this discussion, I think it is important to remember the reason Farhan created the BITX rigs:  The goal was to get today's radio amateurs out of their Yaesu-Kenwood-Icom appliance rut, and get them involved with the circuitry, to get them to modify and improve the rig.   And that's precisely what is going on now.  

It was well known that dual conversion is riskier than our old familiar single conversion architecture -- when you throw another mixer and oscillator into the rig you open the door to  problematic spurious signals..  But dual conversion holds out the promise of general coverage.  And the advantage of that is quite evident in the uBITX.  Mine is on right now and I can switch from band-to-band with a press of the tuning control. This is nice.  So a spur has been discovered -- solutions are already being offered.  That's the spirit!   And it looks like the low pass filters might not be as effective as hoped.  This may be a simple matter of board layout and relay use.  That is clearly quite fixable.

So let's remember that this is not plug-and-play ham radio. This is more of a collaborative, homebrew, open-source hardware/software project.   The uBITX may be closer to true homebrew than many hams are accustomed to.  That was the whole idea. 

Patience is a virtue
Possess it if you can 
It is never held by techies
And seldom held by hams  

Where it belongs: S38E in a Zoo

Hey fellas,

Hope this finds you well.  Spent the day with my family at a zoo.  They have a neat African exhibit that includes many small huts for shade and to give the feel of the African bush.  Each was outfitted with items kne would expect to find in a distant bush camp... Gear, etc.  Many had semi modern radio receivers. 

But one...  One had a well worn and rusting Hallicrafters S38E.  The rig y'all love to hate... Lol. It is secured to the shelf and as far as I know stays their year round; partially open to all the wonder weather Michigan can throw at it. 

I got a kick out of it, thought you may as well.  

Hope all is well.

John in Michigan 
KE5ETX

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John:  Finally, a good place for these things.  Museums. Or Zoos.   We should organize a collection campaign, perhaps with free pick-up and tax deductions.  

Here is a no-kidding story.  We had a family reunion last month.  I met a cousin I hadn't seen in 40 years.  I had given him an old S38E so he could listen to SW BC.   I asked him if he remembered that radio.  "Yea, I sure do -- It almost electrocuted me!"  

73  Bill 

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VA3IAW's BITX 40 Box. Ugly? I don't think so.

Al VA3IAW thought he had a shot at the "Ugliest BITX 40" award, but I shattered his dream by declaring it a thing of beauty.  He made it from PC board material and 1/4 inch angle brackets.  That's a paint stirrer supporting the mic element and the PTT switch.   Al might want to use shielded cable for the mic if the waterfall policeman on 40 meters detect RF feedback and freak out. 

The CHIME Radio Telescope and Fast Radio Bursts

The new Canadian radio telescope is very interesting.  It has a great name for a radio telescope:  CHIME  

And it it always nice to come across a reference to the Parkes Radio Telescope.  

More info here: 

https://www.theregister.co.uk/2018/08/03/fast_radio_burst/

And here: 

https://en.wikipedia.org/wiki/Fast_radio_burst

Good luck on getting a QSL from the FRB station.

WA4GEG's Beautiful HB Transceiver

http://www.hamradiobug.com/homebrew.html

Pete spotted this.  Beautiful work. I noted that Byron hasn't used the Manhattan style of construction.  This makes his work look a lot neater, but it makes it harder to modify and debug the circuitry.  On the other hand, OM Byron is obviously so good at this that his circuitry probably doesn't require any debugging or mods. 

The red S-meter and freq counter give it a slightly menacing appearance.  Very cool. 

Wow. Mr. Carlson's New Old-Time Radio and Test Gear Lab. VE7ZWZ -- Homebrew Hero

It has been a while since we last visited Mr. Carlson's lab.  As always, we found it amazing.  The awesomeness just keeps increasing. Previous visits: https://soldersmoke.blogspot.com/search?q=Carlson

As was the case before, this is really almost too much.  THREE DX-100s in the shelves.  A massive collection of tubes, some sorted, some un-sorted.  But don't worry -- Paul has a good memory and remembers where everything is.  I believe him. 

For his amazing shack and workshop(s) and for his willingness to repair old-time test gear, Paul VE7ZWZ clearly deserves homebrew hero status.  

Thanks Paul. 

On-Board your Arduino Board with an HCC Board

Nice, but the toaster oven is kind of scary. 

A Rig with Maximum Soul: The 5 Band Transceiver of Glenn KU4NO

That's the front panel.  Glenn's kids and grand kids liked sitting on his lap while he played radio and putting stickers on it

This is one of the best HB2HB contacts I've had.   I was just getting ready to sign off on 40 meters when I heard someone calling me. It was KU4NO.  I thought I'd just give the OM a quick report.  Then he said, "My rig is homebrew too."   And wow, it is indeed!  When he said this my first thought was that maybe this was a kit rig, but no, it turns out that this rig is the scratchyist of scratch-built rigs -- true hardcore hardrock homebrew. 

I checked my log.  I had worked Glenn once before, in December 2001.  I was in the Azores.  And he was using this same rig.  Glenn told me that for all these years, this has been his ONLY rig.  A friend gave him a modern commercial rig, but he prefers this one.  I understand completely.  

At first, Glenn made me promise not to share the pictures with anyone. He seemed a bit embarrassed by his creation.  I told him that SolderSmoke readers would appreciate his rig and see the value of it. I explained that we all have soldering iron scars on our fingers, and clothing that has been stained by ferric chloride.  We LIKE ugly.  It took some persuasion, but I got  him to agree to let me share this with the group.  

Glenn reports it is based on a "5 band transceiver" circuit in the 1976 or 1977 handbook. (i don't have one and can't find it on-line -- can anyone get us a copy of the schematic and article?)

So I say THREE CHEERS for Glenn KU4NO and his homebrew 5 band transceiver.   For me, the stickers are the most important feature of this rig.  Please e-mail me your comments on Glenn's rig - in an effort to let him know how much we appreciate and understand his effort, I will pass them on to him. I wish more hams would follow his example. 

Glenn wrote: 

Oh well I'm not too concerned about who sees it. 

I just wouldn't want to cause anyone to follow my example. 

Maybe you could call it "a tornado goes through a junkyard."

Just kidding around ...no restrictions...I'm sure it will be forgotten soon ..... but I will be innocent of any harm caused by it. 

Its the only rig I've ever owned when we contacted before it was with it. 

The inspiration article in the 76 or 77 handbook is worth a look.  

The VFO tuning cap and mount came from a CB "slider" one of my brother-in-laws gave me  it seems to work well

 

Glenn

Picture Above:  top view upper left power out two IRF 510s from w2eby ( I think) 30+ to 60+ watts across HF love this circuit, small board connected at right angle is 1/2 watt driver from Harrys Homebrew page 2n2222 driving 4 2n2222s beautiful circuit

lower left power transformer 

one of two wafer band switches in middle   ....  under wafer switch is hf mixer and single balanced mixer to generate ssb

 LO from progressive receiver top right ... heat sink just to left and lower unused voltage regulator

  RF amp and wafer switch lower right used for transmit and receive

 

LO tuning cap and hf mixer modulator circuit

 

 RF amp

 Crystals for mixing, BFO, old detector circuit.  Old circuit that repeated CQ call, chip from Radio Shack

Some micro relays ...... audio amp at bottom and two switchable compressor circuits one using an SL 1626 and one lifted from a President model CB radio  and some filter caps

 

New IF AGC audio detector uses three ca 3028As from 67 handbook schematic is wrong can you find the mistakes? it was printed wrong twice i use an s meter with it

Close up of power output and lower left  rf output filters  

 

Homebrew Juju -- HB2HB

Oh man, last night the Radio Gods were on my side.  I only had about a half hour on 40 SSB, but I had some really nice QSOs.   WB2HJK George in NYC was very interested in the BITX revolution.  W3BT in Philadelphia is a kind-hearted OT who ran an ENORMOUS Yagi atop a row-house in the city -- the antenna extended over the street and TWO of his neighbors houses.  Never had a TVI problems. FB.  SS listener WA3O Mike called in -- Mike is the fellow who gave me my HW-7.  Mike has been running his uBITX into a homebrew 500 watt LDMOS amp. FB Mike.  

Then the real miracle happened.  Just as I was about to throw the switch, Glenn KU4NO called.  I decided to give him a report.  But then he said something I rarely hear:  "My rig is homebrew too!"  I checked the log -- I had spoken to Glenn before, but our last QSO was in December 2001.  I was in the Azores.  Glenn was on the same homebrew rig.  We had a nice talk about his rig.  FB.   

Glenn told me that in all his years on the air, he has only had a few contacts with other homebrew stations.  He had a list of them:  1) W4ZCB, 2) N6ORS (FB! SS Listener!), N2CQR ("No wait -- I just heard you but we didn't talk.") and W2JUQ.  I will tell Glenn that he needs to add CU2JL to the list -- that was me in 2001 and I was indeed homebrew DSB.) 

To top it all off, Dino KL0S was listening and recorded the final part of the QSO.  See below. (The video might take a few minutes to load.) 

In honor of that FB night on 40 I am re-posting the animated GIF of my BITX-17 build.  I hope it doesn't make you seasick!  

Also, I think we need to add a term to the SolderSmoke lexicon:  Juju.   As in Homebrew Juju. See:  https://en.wikipedia.org/wiki/Juju   Right?  What do you think Steve Silverman? 

Homebrew Tuner for Doublet Antenna

For now, I've put the Moxon project on the back burner.  I will take it up again once Old Sol starts showing some spots.  In its place a 135 foot doublet is going up.  I got at a hamfest a while back.  (It is the only HF antenna that I ever bought!) It is the SPI-RO Manufacturing Company's Model A-10.  It came with 100 feet of 450 ohm window line.   It will be up on the roof soon.  

Today I put the tuner on the wall in the car port right outside the shack. I even built a little shelf for the SWR meter (used one of those Whole Food grilling planks!).  I put a 25 ohm resistor where the feed line will connect.  I was able to tune it up on the two bands I tried: 40 and 17.  

There is a smaller coil inside the big one -- the smaller coil resonates with the lower variable cap. 

You can see all the homebrew rigs in the background -- waiting patiently for the antenna.  

I actually built the tuner back in 2012, but never used it.  Description here: 

https://soldersmoke.blogspot.com/2012/01/2012-off-to-good-start-balanced-atu.html

I will try to provide a schematic and more details soon. 

Mars Weather Update: Dust Storm Continues

https://www.skyandtelescope.com/astronomy-news/is-the-mars-opposition-already-over/

The Moxon Files from L.B. Cebik W4RNL

I had thought that the Cebik files were lost to us in some sort of legal copyright struggle.  But in my effort to better understand the Moxon antenna, I found a real treasure trove of Cebik's writing.  These should all be saved somewhere safe. 

I especially liked his description of the evolution of the Moxon antenna.  Les Moxon was apparently very unAmerican in his emphasis on reception (not transmit gain)  as the main benefit of the beam antenna.  He also sought to avoid superfluous luxuries like rotators, but Cebik hints that rotators have become an important part of our American way of life.   Indeed.   
Before I found these files I had been on the verge of giving up on efforts to replace my storm-damaged Moxon.  After all, solar minimum is still ahead of us.   But after reading OM Cebik's articles I have decided to build a 20 meter version and place it above the center point of a 130 foot doublet.  I will have the best of both worlds.  

http://www.antentop.org/w4rnl.001/mu0.html

http://www.antentop.org/w4rnl.001/mu2a.html

L. A. Moxon, in his HF Antennas for All Locations, provides the essential clue: "the main benefit [of a beam] accrues from the reduction of interference during reception, though the 4 to 6 dB gain provided by typical amateur beams is an important bonus and probably the reason which carries the most weight with the majority of amateurs."⁽²⁾Here is a theory of beam operation quite unAmerican is style: instead of gain, Moxon strives for front-to-back ratio as the most crucial aid to ham operation. His statement is an affirmation of the "good ears" theory of operation. Even more, it forms the basis for his rectangular improvement upon the VK2ABQ square.
...
 Moxon prefers matched elements, tuning each of them to optimum performance remotely. That way, he can reverse the beam and do away with expensive and maintenance-intensive rotators. However, rotators are a way of life in the U.S. (a TV rotator will likely handle a 3-band Moxon beam), and there are many uses for portable beams that are hand-rotated or fixed in the field. Thus, I decided to continue the exercise in unequal element lengths.

http://www.antentop.org/w4rnl.001/mox20.html

Finally, a treasure trove of Cebik's writing: 

http://www.antentop.org/w4rnl.001/radio.html