Posted on June 16, 2017
Posted on June 16, 2017
I wasn’t in the market for a new amplifier, but when looking at the new Elecraft KPA-1500 (and realizing the price would never get board approval), I looked at competing products and found this one. I read the reviews, looked at the price, and as soon as I sold my old car – I ordered one.
First of all – its a dream footprint wise and it has a very nice setup / config interface – its very intuitive and the manual got me started right away. With the cable Dan made, the amp tracks the K3 perfectly. Some things to note:
- It does put out 1.5 KW no problem
- The drive you need to give it is tiny – lower than what you have to give the Elecraft KPA-500 (and that as already low)
- The tuner reminds me of the ACOM 1500 which is that it will match up to a 3:1 SWR, (the Elecraft KAT-500 range is much better). Luckily, my 40M phased array, home brewed 20M yagi and the “Mod Bob” on 160M are resonant on each of those bands – so I have three bands that do not require an outboard tuner – and the 1.3K covers each of the entire bands, which is great. When I run high power I try extra hard to offer a good SWR right at the antenna. I do need an out board tuner for 80 and 30M – and that’s what the Palstar BT-1500A is for – it will be mounted in a weatherproof box out back right at the antenna at some point – I will experiment with it this weekend. Maybe I will finally build that remote synchro or stepper motor drive for the BT1500A – make it Arduino based. That should almost be an “out of the box” project, but we shall see. It all depends on whether or not I also need to switch in the Hi and Lo Z portions of the BT1500A, or if all I need to do is tune the two front panel L and C control knobs. Anyway all of this was baked into my decision to go for the BT1500A, but I digress . . .
Bob and Dan at Expert Linears were the best to deal with and I highly recommend them. I loved my ACOM 1500, but I just found the next step up in my amplifier pursuit, and the price was right in my budget. I very much see why people have ranted and raved about this excellent Italian amplifier – and Expert Linears America, LLC (the US Distributor).
I do think it will make a difference on 160M and because the bands have been so lousy – I’m thinking more and more that full power will be needed for Bouvet . . .
I will keep the KPA-500 and KAT-500 as backup.
Posted on June 14, 2017
My all time favorite rig is the K3. I’ve owned my rig since 2008, so its by far the longest I’ve had one rig. Its what got me to Honor Roll and even after all these years its still seems like quite the performer. I also love my KX3 for portable work, and previously loved my Ten Tec Orion II, but I will keep the list to just one product in each category. I know a lot of people have moved to Flex gear, but I have no desire to.
SPE Expert 1.3K FA amplifier. The best amplifier deal out there and as many others have mentioned “a game changer”. I’ll be dedicating a full blog post to this shortly. I had no intention on buying another amplifier, and was seriously looking at the new Elecraft KPA-1500 (since I love my KPA-500 and won’t sell it any time soon). For a tube amplifier, the ACOM 1500 is by far my favorite tube amplifier and was sad to see it go, but the road to Top of Honor Roll and 160M DXCC is a long and winding one equipment wise. Selling my car funded this.
The N6BT DXU-32 and AB-577 Tower combo. Best high AND low band (TX-RX) antenna system ever – hard to believe I had the “audacity” to put it up – but glad I did. Twas great to experience being one of the first ones on the West Coast to get through several massive pileups to very rare entities. I have no regrets selling it and switching to a low band station, and love both my “Mod Bob” and phased vertical arrays, but I have to admit – I was a “semi-big-boy” for a couple of years.
Remote switches – DX Engineering. Their 8 position remote switch is one item that I was really impressed with – and this DVA-40-P is not only a fantastic 40M phased array – but turned out to be a great 160M RX array.
Wellbrook ALA1530LNP receive only antenna. I’m still blown away by its performance, and more than a little embarassed that its was the last RX only antenna that I tried.
Palstar antenna tuners – any of them. They are by far the best “analog” / manual tuners out there.
Best SWL receiver – Palstar R30CC – for SWL and BCB DXing. It “hears” everything my K3 does, and its audio quality is like a tube receiver – very warm. It is better for AM broadcast stations than the K3, but I’ll take the K3 for CW.
Astron RS-35M linear power supply.
K3ZN – for my “touch”, Tony’s keys are my all time favorites.
I love my Koss Pro4S headphones – they are so well built (aluminum), are light, very comfortable, and sound the best for CW, SSB and even AM broadcast. Very clear, non fatiguing.
My favorite microphone, even though I am on CW twice as much as I am on SSB, SSB is still important in my DXCC goals. There are several ATNO’s that I have that were SSB only.
I did not use a rotator on the N6BT DXU-32 but used the AB-577 “spanner wrench” Armstrong style. I was much more comfortable with this because unless you buy a very expensive rotator, I just don’t trust the lighter duty ones. Because I usually park the yagi in the direction of a DXpedition, I say the heck with them and that they are just a failure point ready to happen. I don’t have one on my KY6R two element 20M home brewed yagi.
I have gotten my money’s worth out of this antenna analyzer 100 times over – its a wonderful piece of gear, and is really great with the Ant software.
The Fluke 115 is used all the time at Chez KY6R
Posted on June 13, 2017
May, 2017’s average sunspot number was 18.8, which is about what it was like for VK0EK. In fact, the average for this year is somewhere close to this. This snapshot is from the spaceweather.com web site, and it differs from the NOAA website:
The difference is not the “actual”, but the Predicted. In both cases, the real average has consistently under performed the predicted. What has been most interesting to me is that spaceweather.com had updated their prediction to include that “knee” – and it is as optimistic as you can get for where we are in this cycle. We truly are flirting with the bottom of the cycle. The top of that little “uplift” will be this coming October – only 4 months away, and while that’s the “last gasp” of somewhat “OK” solar conditions – things will still be OK in January, when 3Y0Z is on the air. In fact, September and the Autumnal Equinox is only 3 months away – I must be really busy at work – time is almost going too fast these days! I mean – we are scraping the bottom of the barrel here – but for such an under performing cycle – its as good as it gets. I expect some very good conditions this Fall and Winter – but they will be short and sweet. This does bode well for Bouvet!
It does seem quite ironic that there is that “knee” and even an uptick that might occur in October, 2017 and that conditions will still be “elevated” from what NOAA predicts through January, 2018 – and then we will most definitely quickly drop to the bottom.
Lets compare what they predict for the Bouvet DX-pedition and what I worked at the same time in the last cycle with very similar conditions. Conditions in September 2007 were the same as they are now:
3B7 is pretty close to Tromelin
3B7C – Agalega and St. Brandon. This one is the best clue as to what to expect because it is much farther away than 3Y, and I know for a fact that I worked them Long Path. In fact, for one QSO, I was in a minivan parked with a 102″ whip, IC-706MKIIG and an AH-4 tuner over the end of the Prosser Creek Reservoir just north of Truckee, CA. And I worked them on 40M this way! Its was the most amazing thing – their signal at sunrise was simply amazing and I never ever expected to work them this way. I remember that Winter was not far away in the Sierras at that time – it took some hot coffee to keep me warm.
I worked them on the Long Path on 80, 40 and 20M, and Short Path on 30M. I remember their operators and signals were just the best of the best – The 5 Star DX Group – who are the world record holders for most QSO’s with their T32C DX-pedition.
Here is the most hopeful news. I worked these other entities for ATNO’s:
- BS7H – Scarborough
- D60VB – Vlad in Comoros
- VU7RG – Lakshwadweep
- 3B9/G3TXF – Nigel on Rodrigues
- VP8LP – very surprisingly on 12M
Besides VP8LP, all were 20M or lower, except Vlad on Comoros – which was 17M. That opening to Vlad was very short – maybe 10 minutes. VU7 was open for about 1/2 hour – but very workable for about 20 minutes only. All of this is good DX, and quite rare – proving that you just never know when you will get those breaks. I also know that in 2010 I had a few like this – and the conditions were also this “bad”.
Comoros, St. Brandon, Rodrigues and Lakshwadweep are actually not entities that I would ever expect to work given “the numbers”, but there almost seems to be some “antipodal magic” going on here. Lets see what Father John – ON4UN says in his “good book”:
Sure enough – on pages 1-34 and 1-35, John discusses “Antipodal Focusing” and Signal Ducting, and I am sure that this must have been the case for me in that mini van. Its one of a handful of QSO’s that I will never forget.
Here are my recommendation(s) –
- Make sure you are there for what will be pretty short openings
- Make sure you have good Low Band antennas, but 20, 17 and 15M might also be good. The lions share of the QSO’s will be 40 – 20M – I am SURE of this
- I do think having full power will be needed as well – although the team is very good about working out the band and giving everyone a chance. I have a story about my power situation – in a blog that I will post later this week. One reader will give me hell I am sure!
Posted on June 12, 2017
I’m very pleased that my “Mod-Bob” antenna ended up being one that used “tuned feeders”. Well – therein lies the rub. I don’t really, really understand this antenna – because it seems to look like three phased verticals like a Bobtail Curtain – but does so on 30M as far as EZNec is concerned. But the feed is not at all a classic Bobtail feed – because I am not feeding against ground radials – which would be a voltage feed. Instead, my feed looks more like a dipole current feed.
Here are some simple, yet very easy to understand references to look at for a 1/2 wl dipole feed:
and a 1/4 wl vertical feed:
I’ve heard conflicting opinions regarding the efficiency of an “L” tuner circuit vs. the more common “T” circuit, but the Palstar BT-1500A is designed for open line feeds to the antenna. It has several switches and settings to allow for high and low impedance matching – and seems like I will be able to learn a lot from this antenna and project. The manual is very good – its an education in itself, but with my very trusty and well used Rig Experts AA-30 antenna analyzer and “field laptop” (an old Dell “beater” laptop that can go out in the yard with me), I will be able to try different settings on the tuner and measure what happens with the AA-30. I’ll learn right away if I need to run a 12v line out to this remotely installed tuner – or if its “default” switched circuits are good on all low bands.
I do know that the antenna is 50 ohms on 160M. What is interested is each “side” of the feed is 117 feet long. This is almost 1/2 wl on 160M – which is pretty cool for a 160M antenna that fits in a small suburban back yard. So, for starters, the impedance is LOW on 160M.
I know for a facty that on other bands the impedance will swing high – I suspect that on 80M it is especially – because the KAT-500 does not like the SWR much at all and I’m restricted to 200 watts or so there. Otherwise – on 160, 40 and 30M its fine.
The AA-30 will give the full story – and then, by switching in combinations at the antenna where the BT-1500A will be mounted – I can really get down to business and document this antenna from a feed point perspective.
The actual measurements plus EZnec plots will be useful – I like “data visualization” because its a way to take a complex set of variables and produce something a non EE person like myself can understand.
I build data warehouses for a living, and love to get to the “art of understanding” with “visualized data”.
Posted on June 12, 2017
On Friday, I sold my car and now we are a one car family. I’ve wanted to do this for many years, and the whole hub bub regarding the Paris Accord made me finally do it with conviction.
I also had an epiphany after toiling over the nasty political climate in the US. I kept reminding myself what I was taught in the Episcopal Church and something my father said. The Church taught me “Do unto others as you would have them do unto you”. My father was much more succinct, he said “If you don’t have anything nice to say, don’t say it at all”.
My epiphany was that no politician will ever save the world. In fact the truth is that people must contain politicians from ruining the world. Taking sides on social media is downright idiotic. So, as I mentioned in my previous blog, I will be very careful to try to channel all of my energy to positive thoughts, words and most importantly, deeds.
Imagine if every one on the planet consumed less, wasted less and walked just a bit more softly.
This no “Kumbaya moment” since I’m saving for retirement, I already know that these actions can help save big money. My grand parents lived this way when they immigrated and went through the Great Depression. Modern convenience (with massive waste) was an invention that happened once the US economy recovered. There is no amount of money or no political organization that can come close to the power of the people. And we don’t need to organize, this is something each of us can do.
I will blog about the ways that I plan to contribute to society and the earth and let you know what happens. Becoming a one car family is already an incredibly freeing thing. Not only do I not miss my car, my mind is now open to being more creative in how I get around.
I’ll only blog about things I actually do in this regard, but the thing I like about what Mahatma Gandhi said is that it takes the Christian “Do unto others” idea or the Buddhist idea of “Do nothing extra” and steps it up a notch. It transforms this to a question of what can I DO.
Going from a two to a one car family is a pretty good start and now I’m thinking creatively on what I can do next.
Posted on June 11, 2017
40M Phased Array verticals at KY6R. There are 44 buried radials that connect between each vertical plus chicken wire ground screen not connected to anything. The chicken wire helped hold the radial wires on the ground – and then the grass grew over the wires. This ground system seems to work exceptionally well. The creek bed is just below these verticals to the right.
One of the reasons why I deep-sixed my old blog is that I had some posts that were getting really out of date – and I mean a LOT of them. Back in the day, I was very much into Cabella’s Crappie Pole Moxon’s and a Christman fed 2 element 40M vertical array. With more experience (and new products coming on the market), I have found some better antennas and approaches. I’ll get to the Moxon antenna in a subsequent post – but lets take a look at the Christman phased array “replacement”- the DX Engineering DVA phased vertical array system.
One of the things that I have come to love is the DX Engineering DVA-40-P 40M phased array system. DX Engineering will sell you the entire kit – and its kind of expensive, but luckily, I had the aluminum for the two verticals in the array. I purchased the DVA-40-P controller gear – which consists of a switch and a remote control box – and all I can say is – these guys really know how to build some serious gear – and the outside switch has the absolute best gasketed weather proof case I have ever seen. Its also UV protected – which believe me – is super important. I was feeling lazy, so I paid them to build the phasing cables – you can save good money if you do it yourself.
In the old blog I sang praises of using an Array Solutions Stackmatch II switch and cutting the 3 antenna cables (2 feeds and one delay) using the VA7ST Christman calculator available online. The approach is well documented in the ON4UN Lowband DX-ing book, but I now think the DX Engineering approach is far superior. Its the same thing electrically – but mechanically, I feel like the DX Engineering approach is better.
I can say without hesitation, just go to the DX Engineering web site and purchase their gear. Yes, it will cost about $200 more total, but believe me – it is well worth it. One reason is the durability and weather proof part – the other is you only need two cables from their phasing switch, and no set of crazy coax T and L connectors. Its a much more “elegant” solution – and that means a lot when you want something to work over several winters, and heck – even the heat of summer.
The delay line is essentially replaced by a toroidal transformer. These units would be very easy to repair in the field if need be.
What is especially nice is having two simple feed cables and no delay line. Its VERY easy to cut the cables incorrectly, and if you do – your phased array will be a very disappointing exercise in futility. With the DXE boxes and cables – the only thing I had to do as build the two verticals (I pop rivet and use Alumox on all of the top sections and then use a bolt at the first section so I can slide the element up and down and tune each element per DXE’s very well written instructions), and using my Rig Experts AA-30 antenna analyzer. In fact, it took maybe 1/2 hour per vertical to tune it to the frequency that the DVA manual suggested so the center frequency would be at 7.150 mhz.
I even purchased a second unit – so if one blows up, I can actually fix it myself. I will have no downtime this way, and believe me – when Bouvet hits the airwaves in just months – you better have 40M in your quiver of antennas! Conditions on the high bands have been so close to bottom of cycle conditions – I am thinking that the 3Y0Z propagation predictions are actually a bit optimistic. I hope I am wrong, but 20M is EXACTLY like it was at the bottom of the last cycle – there are maybe 3 or 4 stations on the air – and they are just US stations – no DX. They are all weak. Yes – there is an occasional spike – but this downward trend is real and somewhat “alarming”.
During the last bottom of the cycle – if I did not have a 2 element phased array on 40M, I would have almost just shut down the station for 2 or 3 years.
For two years I had the N6BT DXU-32 and had to take it down so I could get serious about 160M, while retaining something decent on 20 and 40M.
The DXE DVA-40-P is not quite as good as the 2 element “shorty” 40M yagi I had up at 50′, but its not too far behind. The difference between the two is when you will get in the log – with the phased array, you will be in line right after all of the full sized and shorty 40 yagi owners – and you will be before the high dipoles and the 41′ verticals and low dipole and inverted vee DX-ers.
Here’s something to consider – 2 phased verticals close to ground is childs play to maintain – even a high dipole (with squirrels eating through my support rope) was trickier. And the DXU-32 on a tower – that was a massive undertaking compared to the phased verticals. Also – if you have an HOA or CC&R – you might get away with two aluminum or wire verticals in your back yard.
Again – if you want to work serious DX and rare ATNO’s in the next 4 years or so – you better have at least a 2 element phased array – and the DXE DVA-40-P is the easiest way to get serious fire power on a small lot!