So, How Does The Remote Palstar BT1500A Perform With The KY6R Mod Bob?

I have been told by The Mission Trail Net that my 75M signal has never been better – and quite a few people said “Are you in my driveway, what did you do?” . . 

I tuned the Mod Bob manually this past weekend on 75M, which is a band that my Elecraft KAT-500 could tune but where the KPA-500 only tolerated about 200 watts before it faulted. That was a clear sign that an L style latching tuner in the shack could not handle the load. I am sure that a Palstar AT2K tuner in the shack would have handled it – but I believe having a 60′ run of coax from the tuner to the antenna with a 1:1 current choke incurred some very serious losses.

The Palstar BT1500A is absolutely the perfect tuner for the KY6R Mod Bob

The design of the Palstar BT1500A is very unique, and fits the bill perfectly. Having the 1:1 balun (current choke) at the input where the unbalanced coax is then turned into a balanced input to the tuner is the first big deal. The second big deal is that the Mod Bob feed resembles an open wire feed, and the impedance varies depending on band. The fact that the BT1500A lets me switch the shunt capacitor at the input or output of what is essentially a Pi circuit adds amazing flexibility, but as I mentioned a few posts ago, this is the circuit that I use for 160, 80 and 30M:

I was lazy before and either used a Palstar AT2K in the shack with my trusty old ACOM 1500, and the KAT-500 with my trusty old KPA-500, but when I stepped my game up to the SPE 1.3K FA, and have found that its not quite as forgiving as the ACOM 1500 was, but the KPA-500 was also not as forgiving as the ACOM. That’s something you will need to understand when you switch from a tube amp to a solid state amp. You can’r be as “lazy” with your antennas because solid state amplifiers with ATU’s should NOT be used with external tuners unless you disengage the internal ATU.

In fact, my new “mantra” is to make all antennas resonant – they will have less loss and better transfer of signal, but with the caveat that they aren’t rediculously shortened – like trying to use a 41 foot vertical on 160M with a tuner. At least the Cushcraft MA-160V was top loaded, so if you have to go small – do something along those lines.

I’m enjoying having an antenna that is resonant on 160M but using it on 80 and 30M with the Palstar BT1500A. I feel like I am doing right by my SPE amplifier as well – which is the reason I went to this effort – which on air – is paying off bigly.

Civil, Nautical and Astronomical Twilight

While adjusting DX Atlas – which is a “must” tool to have if you are interested in Low Band DX-ing, I actually started wondering about the difference between these twilights. I am sometimes really amazed that even after what seems like sunrise there is that “enhancement” you get for just minutes on 160M, but that on 40M, the long path can stay open for hours after sunrise or before sunset.

Here is the full story:

And under “settings” in DX Atlas:

An easy way to remember which is which:

Civil – Nautical – Astronomical

6 – 12 – 18

This is important not just for DX-ing but when I ride my bike – its always interesting when I need to use my bike light or when I can still see well enough without it.

Now that’s an interesting analogy!



DXCC => Carpe Diem

Lake Pend Oreille, Idaho. Photo by KY6R

In retrospect, the most important thing to do as a DX-er is to Just Do It. Make Hay While The Sun Shines.

Its funny how time is marked with another kind of clock – we have calendars, clocks and can count the seconds, minutes, hours, days, weeks, months and years, but some times you get that one chance to work a rare DX and you better be ready. Some of these buggers don’t come around but a couple times in a lifetime. By lifetime I mean the life of your DX-ing – which in many cases is just a subset of a lifetime.

I’ve learned how important it is to diversify and try new aspects of our hobby. I used to just sit around during the summer pining for the Autumnal Equinox, which happens to be my favorite time of the year, but I can’t remember when, I decided to stop waiting for “DX Season” and try something else.

Here in the SF Bay Area, June and the beginning of July can have this wonderful mysterious fog. It comes into the Bay and sometimes pops over the East Bay Hills and socks in Orinda. This has happened now after last weeks 100 degree week long heat wave. This weeks and last weekend were perfect days to work on my antenna – rain stopped more or less in May and we don’t get a drop until usually one day on October, but really, it doesn’t start again until November.

Today is the first day where the days start getting shorter again – by one minute.

I do wonder about the 3Y0Z Team and wonder about raising $200K that they need. That seems to be an awful lot – but I also know that this team is perhaps the best of the best – or maybe head to head with some of the “5 Star Teams”. The principles of this team have been on 10 DX-peditions of the year, and no other DX-pedition Leaders come close to that.

My 160M goal this summer is to perhaps work between 1 – 3 new ones. As far as Top of Honor Roll, there is 3Y0Z and Glorioso left. I am convinced that when Glorioso happens next time I will need to use a remote or perhaps satellite. I wonder if DX-peditions might start using satellite more at the bottom of a cycle.

Speaking of that, an email just popped in my inbox with this very timely video:

When we get to the bottom of the cycle, I dream of the years where 160M all of a sudden comes to life. Having been through years of getting my Top Band antennas together, I fully understand why DX-peditions usually don’t pay as much attention to Top Band. About 1/2 of the Mega DX-peditions actually do a good job on 160M, the other half have been very disappointing. FT5ZM, K5P, TX5K, K9W and VK0EK all did great jobs on 160M. There were quite a few in OC-Pac in recent years that were just about non existent.

OK – back to the Maker stuff – DXCC and DX-ing has been really boring lately – the last new one on any band was over 3 months ago – so there has been basically no “DX-Citement” in the KY6R shack. Even the ZS nightly and morning paths have dried up. Luckily, that has been replaced by excitement in the Maker world and by going to Dayton, receiving DX-pedition of the Year and re-tooling the equipment in my shack.

I will be fully prepared for the Fall and some DX-peditions that I have heard rumors about – where I will need to have my low band antennas together.

Speaking of that – I am giving the 9 AM presentation at the Pacificon Antenna Forum, and my presentation will be a modified version of one I gave at the East Bay Amateur Radio Club (EBARC) in February.

The corollary to Carpe Diem is Tempus Fugit – I have been at Credit Karma and so busy at work that I cannot even believe that the second quarter is up – my first three months there have just flown – and in no time flat we will be at the doorstep of the fourth quarter, Pacificon, and like I said a few exciting DX-peditions where I will finally get to add some Top Band New One’s.

OK – so today will be 1 minute shorter than yesterday. We’ve turned the corner and Top Band lovers get that extra minute of darkness!


Amazing Maker Tool: Fritzing

Fritzing is an amazing application that can take a picture of a breadboard that you draw, and with one click:

Show it as a schematic, and then:

Show it as a Printed Circuit Board layout (that you can then send to a fabrication shop and order online,

And show your code that is associated with your project.

Now think about it – isn’t combining “Making” with Ham Radio pretty cool?

Ubuntu Bash on Windows 10!

SSH into the Raspberry Pi from Windows 10 Ubuntu Bash

On Windows 10, the “Creator” version, there is a great feature that is Beta and unchecked (not turned on) after you get the Creator upgrade. Its more than just Bash on Windows 10, its Ubunto. It comes with most of the Linux utilities, so the first thing I did was uninstall Putty. Its pretty amazing to have a real shell and that it be compatible with Linux. This means I seriously don’t see why I’d buy a Mac again. I’m still angry that I had a very nice, powerful but expensive Mac Tower that they just discontinued support for the OS – I think it was 10.4 or so. I swear Apple makes its money by “planned obsolescence”.

I’ll take this inexpensive Asus laptop with a larger monitor, 8 GB of RAM and 1 TB disk for $500. And I can do all the development I want just like I was on a Mac or Linux box – plus the Windows native apps are far better than the cheesy stuff on the Mac.

Tuning The Palstar BT1500A With Two Rotary Encoders

This tutorial gives me another part of the puzzle – it looks like a rotary encoder has 4 wires which tells me a lot about how I might use two of these in the shack. If they were wired, the wires would be 60′ long – and I’m thinking that that run is too long. I might try it as an experiment just for laughs – but it sure seems like using the encoders with a control head and sending the commands over WiFI would make more sense.

If I were to go with a wired solution, my entire 8 wire rotator cable would be used up. Since my Rat Pack switch is only using 3 out of its 8 wire line, that leaves 5 wires for voltage for the BT1500A and Arduino remote board. In fact, I could even gang the Ratpack and BT1500A switch power because the Ratpack will always be on – and so turning the BT1500A on at the same time might b e OK.

But going WiFI is truly a great convenience.

Anyway – one more aspect of the project, and I will go find a decent set of encoders so I can play and learn.


Raspberry Pi Communicating With Arduino Uno

Arduino boards are great to dedicate them to one function. In my immediate “use case” I want to have a control box that supplies power and has two knobs to control my remote antenna tuner. I might even add a little LCD to give feedback from the tuner – like what offset the L and C Stepper motors are at.

If I were to control the remote tuner from my laptop via wireless it would be all digital – but I kind of like the tactile feel of analog – not to mention the rotary encoder “knobs” would be right below my SPE 1.3K FA amplifier and K3 – so I could tune and watch their SWR meters. I wouldn’t need to know what the SWR is at the antenna tuner at all – its best to read it right at the amplifier – since that’s the whole reason I even have that remote tuner – to keep the amplifier happy.

SO – while I could do this with my laptop – with its built in wireless, if I do build a box with the encoders and LCD – it could be powered by a Raspberry Pi that talks to my Arduino – which would be out in the tuner box along with the two stepper motors, their driver boards, the Arduino, a wireless board and just the DC wires going out there to power it all.

If I were concerned about the WiFI getting fried by my Mod Bob running full juice – I suppose I could run a 60′ Cat 5 cable – I have to think about this, and this is what my Summer Project will be. I’m glad that this project offers some challenge and fill at least July with fun stuff to do.

One other thing that is super cool – Fritzing:

Its truly the antidote to the “DX Doldrums” . . .