Posted on December 4, 2017
San Francisco and the San Francisco Bay Area is a Mecca for “Living History” enthusiasts like myself. It always cracked me up that while Fisherman’s Wharf was crammed with holiday makers, just a block away there is an Oasis and wonderful world that is a lens into the past, The Hyde Street Pier.
There is also the Cable Car Museum, Fort Point, Fort Funston and the International Street cars running up and down Market Street and along the Embarcadero. There is the Maritime Museum. There is Grant Street with Cafe Trieste, Adler Cafe, City Lights Books and Chinatown nearby. Across the bay there is Jack London Square, Rosy the Riveter Museum. The Radio History Museum is in Alameda. Down South there is the Computer History Museum.
I’m so lucky to have the week off between Christmas and New Year’s because it’s the perfect time to visit these places.
I can’t wait to get my book today and dig into the history of Morse Code. Like Richard Carrington, who had a tough life, it sounds like Samuel F.B Morse did too. But history has been very kind to them as they are known for their significant contributions to art, science and letters.
Here is something I just realized – the history I am most interested in is when man started communicating using technology, and I mean wired technology, not smoke signals or lights or screaming from the mountain tops. The advent of the telegraph – which coincided with the railroad is what interests me the most. It would be until radio was invented before there was ship to shore communication – and I do remember that was one of Marconi’s first successes – was ship to shore radio communication. So – its funny how transportation and communication went hand in hand.
My next phase in Ham Radio will combine the historical aspects of radio and everything before and after. I am going to make a concerted effort to get my code speed up and start long rag chews just for the love of CW. I will also get into QRP, but with the best antennas possible.
I just ordered a pneumatic launcher, and I’m seriously thinking about switching to having one wire antenna after 3Y0Z, a loop skywire or something else that I have never tried before. HOWEVER, the one antenna that I will always keep up is the DX Engineering DV-40-P 40M phased array. That is one of the best antennas that is so easy to put up and maintain and which offers great performance – huge bang for the buck!
Posted on December 4, 2017
I met Ed at Pacificon this year, and he has built some very nice matching devices and also shares a love for Johnson Viking Matchboxes. Our discussions have really helped me learn, and more than just getting some validation on things that I am experimenting with – our discussions help push me forward in the learning space. I have also enjoyed such conversations with Andreas, N6NU and others – who understand the challenges of the low bands and trying to match where high power is used – especially on 160M.
Here are a couple of quotes from Ed that I really appreciate:
“Now sorting out the frequencies of the ham bands as you did in the few days since you posted the initial results, your conclusion is pretty much spot on: You could have a switching network to add the appropriate transforming balun in line. As for the 1:1 feedline isolation balun 1115dt, I would suggest running output of the 1:4 or 2:1 ununs and any other frequency on which you don’t need Rs transformation thru the 1115dt as it leaves the switching network for the shack. It adds the benefit of increased common mode impedance to the signals coming out of the 1:4 and 2:1,and should have no effect on anything else. I use several of Bob’s devices, 1:1, 2:1, 4:1. and 9:1 and they are just fine. He is knowledgeable and fair.”
I just happen to have the 1:1 version with SO-239’s at each end, so adding that is a done deal.
It really is great to get some validation for my approach. I have two antennas that are resonant and where I have nothing to do but use them – my DX Engineering DV-40-P and my home brewed 20M yagi – where I used a solenoid style coil as the hairpin – something Tom, N6BT taught me, and which he did on that fabulous N6BT DXU-32 that I used to have.
But one thing Ed said really has me thinking:
“Now, to specific frequencies, I had no way to expand your data around the ham bands, but note that even in the ham bands with steep resonance (Xs) curves,you encounter Rs not unlike those encountered in any shortened antenna, such as a mobile HF antenna where Rs typically runs in the range of a few ohms, despite a steep Xs curve, These installations use shunt-feed, relying on an inductor across the feed for inductance, and stray capacitance of the installation to translate the typical Zs = 2-6 ohms + jx.xx ohms to Zs = 50 +j0,0.”
I just happen to have this monster coil that Ed gave me – and what Ed is saying jives with what Andreas, N6NU has done with his Inverted L. I have tried a shunt feed before, but found that my coil stock was not exactly right. I have several Airdux coils – but I suspect that they were not wide enough. This monster coil that Ed gave me is something I am going to try before the UNUN’s get here.
Another thing Ed said:
“Nothing wrong with your network switching device, but you might find a length of coax addition that picks up 40 as well as 160 and 80. Who knows! That’s the great joy of out hobby.”
This is really fantastic, because I have to admit, I have never tried using coax stubs as transformers. I just happen to have two 75 ohm 1/4 w.l. coax lines that I was going to use to try to phase two 1/8 wl spaced shortened 160M verticals. That project was shelved, and it just happens that disconnecting the line that goes from the remote Ratpack antenna switch to the 160M Inverted L gives me a very easy little experiment. I have read countless pages in the ON4UN Lowband DX-ing book – where phasing lines, shunt coils and UNUN or other “impedance transformers” are all over that book.
In fact, I opened up the pages where Robye Lahlum, W1MK discusses his matching and phasing circuits. When I first purchased that book – his stuff seemed so advanced, I was overwhelmed.
Now that I have been experimenting “hands on” and because I have had such conversations with Ed and Andres, it is all starting to really make sense. Bob at Balun Designs has also been fantastic to work with. Not only are his products top shelf, he provides great support and is willing to discuss solutions and he also validated my ideas for this most recent set of little projects.
I posted the Smith Chart above because while Ed and I were looking at the Antscope plots where The R, X and Z intersect:
Embarassingly, I had never even looked at those charts, and maybe only ever looked at the Smith Chart much. The upshot is that just by having a discussion, I have learned these things:
- Resonant antennas are easy to match and deal with, non-resonant antennas are hard to match when you want a good match on multiple bands
- The “other” plots that you can look at on the Rig Experts Antscope are a must for such work
- When using coils and capacitors for a feed, you can’t have enough different components to try – and I will try that massive coil that Ed gave me soon
- Stub matching can have the same effect as using UNUN’s and other components – I will try this for sure now
SO, my learning continues and I feel like my discussions with friends who share the same interest really help me take that next step up the education ladder.
Posted on December 3, 2017
I might have spent my early years on the East Coast, but I have lived in California for almost twice as long as when I lived in New Jersey, New York and Pennsylvania.
Don’t get me wrong, I have very fond memories growing up in Newton, NJ and going to college in Lock Haven, PA, but the last time I was back east was 1991. I did go to Dayton this past Spring, so I did get close.
But I love the Western States and the West Coast the most. I’m also eternally greatful that my Father finally took that job at Lockheed in 1979 when he moved the family here.
Interestingly, I could have been born in Los Angeles. My Father, in WWII, landed on the beach in Normandy on the third wave, fixed tanks and Jeep’s and ended up in the push to Stuttgart, where he was born. When he came home from the war, he bought a Harley with dreams of heading for California. Kerouac was born The same year he was, so heading West was an ambition for some in the Northeast at that time. Iam sure he would have ended up in LA, but after a serious motorcycle accident, stayed in NJ.
My Father was a machinist in the US Army, but that was only because he wasn’t allowed to join the Air Force – because he was born in Germany. Never mind that he immigrated when he was 4 years old. He did end up in the Aerospace business.
It’s a beautiful California Sunday morning, and it’s more like an East Coast Fall day. We are going on a nice 35 mile bike ride, and I’m musing about how I ended up here.
I feel blessed and very lucky to have landed in the San Francisco Bay Area as a Computer Science major out of college, and I am enjoying my career more than ever after all these years.
When I first moved here there were next to zero tech jobs in SF – they were all down in the real Silicon Valley, pretty much Santa Clara County. There weren’t even many tech jobs on the Peninsula yet.
Amazing how things have changed.
Posted on December 2, 2017
Schematic drawn by KY6R using Circuit Lab – an excellent web browser based tool.
I use the same relays as Array Solutions does in their gear:
Deltrol 20852-81 12v 35a DPDT – $13 at Galco
I went over the Rig Experts AA-30 SWR plot and found that on every band from 160-10M, one of three UNUN’s or 1:1 Curent Choke will keep the SPE Expert 1.3K amplifier happy. This means I wouldn’t need the Palstar AT2K – at least this works on paper. I just happen to have this control box in my junk box – where the RCS-4V remote switch burned up, but the Control Box can be re-purposed for this project:
Because it injected AC to control the remote switch – using the coax as the control line – I have to rework it a bit and probably remove a few parts or even cut some pads on the PC Board:
The rework . . . and here’s what the new (and simpler) circuit looks like:
Position 4 isn’t used – but could be used for another UNUN or Balun, maybe for a ladder line fed doublet that I might throw up in the trees – like maybe a 17M extended double zepp – pointed at 3Y0Z.
Array Solutions rates these relays at 5 KW- I’m not sure how they calculated that, but I have used these relays before on my Inverted V / Marconi switching, and since these re what Array Solutions uses in their Rat Packs for years with no issues, this will be a fun project to try.
I will have to come up with the voltage matrix. In short:
|160, 40, 20, 15||DWN||1|
Posted on December 1, 2017
Its downright Dickensian . . Karmaic Justice is about to be served up on an icy cold tray. But unlike Scrooge, or the Grinch, don’t expect Trump to grow a heart.
It is really amazing how close to what’s unraveling in the news today was nailed by Bill Maher and his crew. They deserve an Emmy or Pulitzer or whatever award they give TV shows. Its also amazing that Trump – with all his tweets pretty much gave it all away anyway – loose lips sink ships. His firing of Yates, Comey and Bharara was straight out of “The Gang That Couldn’t Shoot Straight”, “The Soprano’s” or “Dog Day Afternoon”. House of Cards is waaaay too sophisticated and intelligent. Its amazing how such pathological narcissism can become your own downfall – not only is all this Dickensian, its Shakespearean.
One thing I know for sure – people don’t lie if they have nothing to hide. They don’t fire people investigating them.
Ironically, besides all of the Russia related news that will now pour out – the real serious issue is that Trump cannot do the job – he is so out of his league and incompetent that its time for him to go. My father suffered from dementia before he passed, and I took care of his affairs and visited him several times a week. The strange tweets regurgitating old tweets from a year ago about the Birther thing and Access Hollywood mixed in with all kinds of new weird tweets this week just seem like what I experienced with my father but times 100.
I would not be surprised if the 25th Amendment will be invoked because there is no way the GOP will have a chance during the 2018 mid terms if they do nothing or stand by Trump. Now I’m wondering who else will be nailed – it seems like there will be many indicted now. Its going to be flip city.
I actually think what will now be a torrent of facts and dirty details will cause the GOP to have a very, very bad 2018. Of course, maybe Trump is their “foil” – maybe he runs interference for them. That’s OK – they will pay dearly for letting treason and collusion stand. We saw the seed of that sown just last month. In some ways I say – leave these assholes to their own devices, but the dems better get their shit together, and better get some young and very powerful blood up front. Their 80+ year old leadership is looking way long in the tooth.
I expect all kinds of weird tricks and legal maneuvers and Twitter rants and threats to happen in response, but its already too late – irreparable damage has been done. Politically, this has been the worst year of my life and I truly worried that our democracy was toast – but now I am thankful that justice might finally prevail. It may take way more time than any of us can stand.
My prediction on this tax scam for the rich – I think there will be as much blow back from it on the repubs as there was against ACA for the dems. Round and round we go. I also do believe we will have a repeat of the Bush Years.
After 2 years of getting a tax break, the GOP takes it all back and more. The idiots in this country will put Trump on the right hand if God, knocking Christ and the Holy Ghost out and the idiots will then wonder what happens in 2 or so years when the well runs completely dry.
Get ready for that!
Posted on December 1, 2017
If it weren’t for 80M, I could continue to just use the Balun Designs 1:1 current choke at the base of my Inverted L. One way to make my Inverted L happy is to put a Vacuum Variable Capacitor in series to the vertical – and use the AT2K Tuner in the shack. Tune the capacitor remotely as I did the URAT.
The second option, which is perhaps easier is to switch in one UN-UN or another, and this is so I can use the antenna on 160 or 80 (schematic above).
The Balun Designs 1435t UN-UN is a 1:4 model and would step the 80M 7 ohms j27.4 up to 50 ohms.
The Balun Designs 2132u is a 2:1 UN-UN and would step the 194 ohms j213.4 on 160M down to 50 ohms.
I am going to try this. It might just turn out that all I would then need for 160 and 80M is the SPE 1.3K built in ATU – which has a pretty small range, but these UN-UN’s most likely would make the tuner happy. I would still need the AT2K if I wanted to use the Inverted L on say 30M or some other band.
Speaking of other bands – the 3Y0Z DXpedition will most likely be good into the West Coast on 17 and 15M, and while I am pretty sure I will get them on 40, 30 and 20, I might try them on 17 and 15 using the Inverted L.
The switching circuit you see above is approximate – I might even add two more relays to switch in a 1:1 current choke instead of the 2 UN-UNs only because then I would be able to cover pretty much any band from 160 – 10M.
I could wire the control voltage so that one “line” is a default switched in line and all others are closed. The natural default would be 160M. Then with basically a simple rotary switch – I could control the three different “chains”.
I could even use an Arduino or Raspberry Pi Zero W to control the relays via WiFi if I wanted to get fancy, but because I still have to run a control line for remote power, I will just hard wire it and control it with a rotary switch. The rotary switch simply sends the plus 12v line to activate each pair of relays – I think I will everything to be normally opened, and then when I switch to a position, it switches in the relay pair for each matching transformer. I like instant switching, so, maybe this would even mean I would no longer need the AT2K at all. I can easily test my assumptions and then use an old Ameritron RCS-4V switch box controller that I have in my junk box (where I burned up the remote relay board) that has a rotary switch and leds and just do a little re-wiring.
I’m going to try it and see – it will be a lot of fun.
Posted on November 30, 2017
I have not taken a new plot with my Rig Experts AA-30 since I changed the antenna from more of a traditional Inverted L to this “inverted fish hook” configuration, so I decided to set the range from 1700 – 15000 khz and see if its any different than the old configuration:
This the OLD plot – when the antenna was a standard Inverted L, and here is the new plot – this time just covering 160 – 20M:
There is a little difference, but not enough to make the antenna appear much different to the Palstar AT2K tuner in the shack – or to the 1:1 current choke at the base of the antenna.
I’m also going to send the plot to Bob at Balun Designs to see if maybe an UNUN might be a better choice than the 1:1 current choke. I doubt it will, but I thought I’d ask – since this is Bob’s expertise.
80M is the only problem band – and I’m thinking maybe I could use the 1:1 current choke on 160, 30 and other bands, but switch in a 1:2 UNUN for 80M.
I’ll update this post after Bob gets back to me. I highly recommend Balun Designs products – Bob is the nicest guy and builds superb quality products at a fair price.