Chitika: Australia

Showing posts with label Australia. Show all posts

Ian VK3MO was booming in from Australia this morning. No wonder: he has a 5 over 5 over 5 over 5 array on a rotatable tower. He can get a 3 degree takeoff angle with this antenna and I think I heard him say that he is working on another so that he can get a one degree takeoff angle. He was also using a using a Collins 30L1 linear. Lots of soul in that old machine!

At one point in our QSO, I turned off my .12 kW amplifier. He said I was still 58-59 with 3-4 watts.

And Ian is a homebrewer! He has built a number of transceivers and has another one in the works. I told him about the BITX and he printed out Farhan's article (to read later). He tells me that he has heard Peter Parker, VK3YE, on the air.

In this QSO, Ian was using a modern commercial rig, but wouldn't it be great if we could get him to connect a homebrew sideband rig to that big antenna. Go for it Ian!

More on Ian's antenna here: http://vk6ysf.com/vk3mo_visit.htm

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Last week during the big St. Patrick's day solar eruption/CME impact I (with the help of the radio gods) managed to work Roy VK6MV in Western Australia. (A video of Roy working QRP pedestrian mobile stations in the UK appears above.) Could it have been that that miraculous contact was ALSO my first ever homebrew SSB to homebrew SSB QSO? I e-mailed Roy to find out. Alas, it was not. But OM Roy sent some interesting info on his station and especially his antenna. Excerpts from his e-mail:

Hi Bill

Thanks for the qso and the email.
yes another 'fadeout' but we have had many over the years haven't we ?
Things have changed a lot since 1963 when I had my first license as G3SML.
We came to Aus in 1977 with 3 sons and now have 24 Grandies 13 Grandchildren; 11 Great Grandchildren.

I liked the early Plessey IC's when they came out ~
Carry on with home brew and get that personal enjoyment out of it, it gives you a boost I am sure. NO I was not on the home brew I was on the Icom IC740 which I bought about 5 years ago at the WA Hamfest it had a fault of jumping to different frequencies, etc. I could not find its intermittent fault at all, but on the internet a 'W' ham in your country posted the same fault with explanations etc,
and it cured it,

So I was on that Rig + a home brew linear pair of old 813's in Grounded Grid and a Voltage doubler for the + 2 kv, I could not get the smoothing caps for that voltage so got hold of 3 metal canned ones 800 volt, then got some plastic drain pipe to insulate the cans from ground & then put them all in series with equalising resistors,
and it worked.
Yes I was on the rhombic ~ amazing antenna for a fixed point to point contacts ~
why a rhombic you may ask well when in the Uk I used to work VK2NN [and others] Tom with his farm of rhombics his setup much larger, and I thought one day I would love to put one up. Eventually with our moving to Aus' then came down here with its 8+ acres the opportunity led itself to put one up, and as I used to work into Europe/UK a lot that direction picked. first I put one up a bigger one than now, but it did not work that good. Moral the longer you go the higher it needs to be
So a smaller version tried using the contours of the land at a height above sea level of 1260 feet asl helps. Using 12 gauge usa hard drawn copper wire I needed winches and turnbuckles etc to pull it up, one end is on the 60 ft tower, the others on assorted Wooden Poles +
The termination R for the rhombic is a 3 element TH3 Tribander ~
think of it why waste power into a whopper of a Resistor ~
this is not my idea but came from ~ Nano VK6UN why not connect it to another antenna with how to do it came from now SK Les Moxon G6XN
a clever man how to make a balun out of old ferrite rods from transistor radios,
Will close now my half a dozen lines of text are expanding to much

Cheers have fun Roy VK6MV

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There I was. 0900 UTC (0 Dark Thirty local), the morning after the big March 17 St. Patrick's Day Coronal Mass Ejection Impact. Solar Flux Index: 116. A Index: 117! I'd never seen the A Index that high. When I got home from work on March 17, I had turned on the BITX 20 and heard nothing but white noise. No signals. Nada. Zilch. So the following morning my expectations for 20 were quite low. I tuned across the whole band, again hearing nothing. But wait... there was one signal. And he was calling CQ. With an Australian accent. VK6MV! The only signal on the band. I called him with my recently fixed BITX20 (with .12 kW amp) and a dipole. No problem. We had a nice contact.
A look at Roy's QRZ page shows that he is a fellow homebrewer. Clearly, the radio gods were making a statement here.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Our British cousins are not a wildly emotional people. The word "phlegmatic" is sometimes used when describing them. Stiff upper lip and all that. But as you can see at the 51 second mark in this short video, contacting Australia whilst using a new scratch-built homebrew BITX20 on battery power from a windy English hilltop WILL get those English fists pumping and those thumbs up. The wind drowns out Colin's voice, but his gestures say it all. Well done Colin! Brilliant!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

That has to be one of the best-looking scratch-built homebrew BITX20s. Pete and I agreed that it looks almost too good to take out into the field. But that is where Colin took it. His BITX was designed for Summits on the Air, and the radio gods rewarded him for his efforts with VK DX. Well done Colin!

Hi Bill and Pete.

Well it just worked out that weather was going to be bearable this morning but getting worse through the weekend. I'm really want to ramp up my SOTA score so I'm trying to get out as much as I can. I switched my plans to an early morning activation on one of the local hills. The hill, called Sharp Haw, is a little lump on the edge of the Yorkshire Dales, it's not very high at all, but it is worth 1pt for SOTA.

The early morning time window brought the possibility of VK QSOs via long path on 20m. I looked at the VOACAP prediction for propagation and it suggested a peak at 0800utc.

I was actually late getting up, my alarm clock batteries have decided they've had enough. Despite the late start, I still managed to get on the air by 0725, hearing a strong Australian accent on the power up frequency of the BITX, 14.200, was a good sign.

At 0737, I was called by VK1DI. I had to turn the AF gain up, but sure enough, the signal was workable and we exchanged reports, 55 for him, 33 for me. Within the space of less than 20 minutes, I had 4 VKs logged, the strongest being VK3DET, giving me a 56. The other two stations were VK3CAT and VK2IO. I also worked an Asiatic Russian station amongst others.

I'm over the moon, I might even apply for my SSB thousand miles per watt wallpaper!

I still find it magical that 25 volts into a bit of 7/0.2 wire can transport your voice across 15,000 miles! Amazing!

73, Colin, M1BUU

Morning OM's,

I've amassed the parts for my 12v Regen Rx inspired by a projects from VK3YE and an audio amp, using a pair of 12AU7's. I'll publish more about that soon on my blog.

In the mean time, I'd like to thank you guys for inspiration on the si5351 VFO in use with various projects. After we found the first articles by NT7S, we discussed that there are a lot of possibilities.

I've just finished my build of an Arduino controlled SDR transceiver prototype using the Si5351A.

See attached images. Lots of collaboration with Mark VK5QI and David VK5DGR. More at; http://openradio.net.au/index.php/OpenRadio_SDR

This week I'm tinkering with the LPF for 20meters. Puts out a whopping 20mW.

Everything is on schedule for the presentation using this SDR at Linux.Conf.Au next year. Got some coding to do to add I&Q for the SDR side over the summer break.

72, Kim VK5FJ

Steve, VK2SJA, is doing to a Realistic DX-100 what I have been thinking about doing to a Heathkit HW-101. With this kind of encouragement, who could blame me for making a Minima-101? I've been planning on keeping the 6146s and all the final (and perhaps driver) circuitry.

Here is Steve's very nice description of his project thus far:

http://www.hfsignals.org/index.php/UnRealistic_Minima

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Podcast #156 is available:
http://soldersmoke.com/soldersmoke156.mp3

Special hour-long interview with Peter Parker, VK3YE
-- Early experiences with radio
-- CW
-- DSB Gear
-- Simple gear, and gear that is TOO simple
-- VXOs, Super VXOs and Ceramic Resonators
-- Building receivers
-- Chips vs. Discrete
-- Making the leap to SSB
-- The Knob-less wonder and the BITX
-- No need for a sophisticated workshop
-- Advice for new phone QRPers

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

There are so many very cool aspects of this project: I love the phasing receiver arrangement -- it uses the same basic concept that allows my old HT-37 to generate SSB (I struggled to understand it as a kid, and finally succeeded!). The use of the mobile phone as an audio spectrum analyzer is wonderful. The N3ZI signal generator looks a lot like the DDS project I was working on (I should have bought N3ZI's! ). I've been seeing these square pattern PC boards in many projects lately -- I may try this in my next project. And of course, it is very cool to see a circuit designed in Poland being put to use by a fellow radio amateur in Australia -- a good example of the International Brotherhood of Electronic Wizards!

Here is the page for the SP5AHT rig that inspired Peter:

http://www.sp-qrp.pl/modules.php?name=Content&pa=showpage&pid=54

It is in Polish, but Google should translate it, and, in any case, we all speak Schematic!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

I was getting kind of worried. I hadn't seen any new articles on Alan's excellent web site. But on my last visit I learned that he has moved to Seattle and is going to Maker Faires: http://www.vk2zay.net/article/268

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

I know that "simple" and "homebrew" aren't the words that come to mind when we think of Software Defined Radios, but minimalist guru Peter Parker, VK3YE, reminds us that with little more than an antenna, a diode, a crystal oscillator and a connection to the computer soundcard, you can dive into the world of SDR.

I've been doing this for some time now, but my receiver uses a 40673 dual gate MOSFET and a universal VXO from George Dobbs, G3RJV. I've been running mine with the FLDIGI and JT-65 HF programs. Peter's video alerted me to the charms of SDRadio from Alberto, I2PHD. This is a very nice program. Of course, I'm always happy to add a dash of Italy to my operations. Thanks Peter! Thanks Alberto! Thanks George!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Oh man, Peter Parker has done it again! As he did with the Beach 40, he has come up with a circuit that will attract a lot of attention. It is a single frequency SSB transceiver with no knobs (or windows, or menus!)

Peter Marks recently had breakfast in Melbourne with VK3YE:
http://blog.marxy.org/2013/05/melbourne-meetup-with-homebrew-legend.html
There are some great pictures of the new rig, and the Beach 40.

Here's the message from VK3YE (to the Minimalist Radio Group) that may
someday be seen as the start of the Knobless Revolution:

Some might reckon that SSB is inevitably too complex to be in the minimalist
class, but I beg to disagree.

I reckon you could build a whole SSB transceiver in 2 days of solid work. I
took a day to build what will be described below up to the stage where it
was receiving & producing a low level SSB on Tx.

Take this recipe:

1. Build the back end of the BitX http://www.phonestack.com/farhan/bitx.html
That is everything to the right of (and including) the Q2 & Q12 stages.

2. Use cheaply available 7.159 MHz crystals in the crystal filter and
carrier oscillator. Keep filter capacitor values the same. Remove L3 in the
carrier oscillator circuit. Use a slightly bigger trimmer in the carrier
oscillator (say up to 50 pF) and wire in series with crystal. Align trimmer
so carrier freq is 7160 kHz.

3. Build a power amplifier stage / relay / LPF as per the Beach 40. Just
the last 2 stages (using BD139s) should be enough. Output maybe 2w.

The result is a 10 transistor / 1 IC SSB transceiver on 7160 kHz. It's
crystal controlled but at least during the day 2 watts to a good antenna
should be enough for people to hear and reply to your CQ calls up to 800 -
1000 km away. Of course you could go a bit more minimalist and remove the
LM386, substituting 1 transistor instead (as per the original Beach 40)
which is what I did.

The main thing that's odd is it has no knobs - no tuning, RIT, volume, RF
gain etc. Just sockets - for mic, phones, antenna and power to feed it what
it needs (Rx RF, Tx audio, DC power) and give what you want (Rx audio and Tx
RF).

It is philosophically different to using any other transceiver. You either
accept what the radio dishes up (frequency, AF gain, mic gain etc) or you
don't. On or off - there is no other state. Take it or leave it. Like a
cat this is a radio that lives on its own terms.

Those used to fiddling with adjustments will find the 'knobless wonder'
transceiver causes them to be at a loose end. Those so afflicted will smoke
more, bite their nails more or eat junk food more. Sometimes elegant
simplicity in radio can be a health hazard - maybe knobless rigs should
carry health warnings.

On the other hand, and in my view this outweighs the above, there is the
aesthetic satisfaction that comes from using a rig that cannot be made any
simpler. Especially if it's a mode, like SSB, that's widely thought
constructionally complex. Plus it takes little in return - the power
consumption will be a fraction of what a commercial rig will demand.

73, Peter VK3YE
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Chitika

VK3MO's 20 Element Monobander for 20 Meters!

More on VK6MV

Working VK6 Homebrew During the Big Solar Flare

Video of The Moment Colin Made his First Homebrew Contact With Australia

Colin's BITX DX From the Field

VK5FJ's Open SDR Rig (Arduino and SI5351)

VK2SJA's Minima in a Realistic DX-100 Case

SolderSmoke Podcast #156 -- Special Echolink Interview

Peter Parker's Video on SP5AHT's Phasing Receiver

Alan Yates, VK2ZAY, is back in the knack!

Simple Homebrew SDR

Peter Parker's Knobless Wonder Minimalist SSB Rig

AHMED HASSAN MOHAMMED

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