Radio

Well, we finally did it. Yesterday Ivy and I bought a bunch of radio gear so we could get on the air.

• Icom 706 mark IIg radio
• Icom PS-300 power supply
• LDG AT-7000 automatic antenna tuner
• Diamond X50 V/UHF antenna
• Diamond SRH-771 HT Whip

We got most the gear from StrictlyHam. Ross didn’t have the tuner so we went to visit Dave from TT Systems. He was really nice and showed us his high power remote antenna tuner project, and even fitted off some coax for us. We couldn’t wait to get to Ivy’s parents’ to start operating. What perfect timing, too. This weekend was both the Lighthouse weekend and the Australian Rememberance Day contest. So after plugging everything in, we tested out the X50 at first on the repeater which could only barely be heard on our Yaesu VX-5, which worked really well. On HF, we were still trying to figure everything out. No matter what we did, we couldn’t get our SWR down. Our dipole was resonant at 1.5:1 for 40 metres, which is what it should be, but infinite through the tuner. Hm. So we ended up listening for a few hours, working out the DSP and other filters. The radio is quite amazing in what it can pick up, compared to the Yaesu FT-707. Early in the day we were able to pick up CE1KR clear as day. South America! Later on a VA2 station from Toronto was on. Only just before the rememberance day contest started at 20:00 local did we finally realise. The bloody tuner was plugged in backwards. I guess thats what happens when you try to operate radio after a few beers.

Once we figured everything out, it worked really well. The contest was a great way to start transmitting on HF. We managed to talk to 30 different Australian and New Zealand stations. We didn’t put a whole lot of effort into the contest, as I had done with previously ARRL V/UHF contests. We ended up going to sleep about 00:30 and listening to the WIA news at 09:00.

Some stations we talked to in Queensland reported we had a strong signal. Quite amazing considering we only have 100Watts and an antenna about 3 metres off the ground. There is much room for improvement, but at least now the upgrades will only be the cost of wire for better antennas

de VK3GNU

Tags: musings, tech by Hannah
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PSK31 has always interested me as a digital mode. Taking up only ~31Hz of audio bandwidth, and a usual SSB signal transmitting ~2.5kHz, you can fit quite a few QSOs in the one passband. This lends itself perfectly to having a single PSK31 call frequency per band, where many people can all co-exist without stepping on each others toes. Today we were finally able to decode PSK31 on 20 metres, at 14070kHz. We heard a signal from the Marshall Islands, as well as W7PTT from Lynnwood, Washington. The fading and noise were pretty horrible. More often than not, the signal could be seen on the waterfall, but all that is heard from the speaker is nasty static noise.

I really look forward to getting a Ic-706 or so, so I can join in.

de GNU

Tags: digi, dx, musings by Hannah
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Tried to build a 146MHz J-Pole using wire, following some of the online guides. It seems simple enough: stick a half wavelength vertical on top of a quarter wavelength matching section. The ends of the matching section have very high impedence, while the bottom is very low. So, somewhere on that path is 50 Ohms. I must admit my ability to construct isn’t the best, so the joints and connections are probably shoddy at best. Ended up using a 150 cm jumper coax bought from a local supplier. Cut one end off and connected alligator clips, one to the braid, one to the center conductor. Made few loops of coax about 4 cm in diameter as an RF choke.  Alas, I’ve been told I have a hum in my transmission. Not having an antenna analyser for VHF, I can’t *really* tell where the 50 Ohm feed point should be, but even just a few millimeters off shouldn’t add a hum. I’m a bit baffled. I guess the best explanation is not enough RF choking, and the microphone or IF stage in the radio are picking up a bit of stray RF. Next will be to add a ferrous material to try and increase this.

Eventually, I hope to build a larger J-Pole for 14MHz. This isn’t a very conventional antenna, but will be the easiest for our situation. Having access to a large tree will allow me to put the ~15 meter tall antenna up rather high. It will have a feedpoint close to the shack, at the bottom of the tree. Best of all, it won’t require a huge amount of radials to get a bit of low-take off radiation happening. Hopefully this will work for a bit of DX on 14MHz.

Tags: antennas, musings, tech, vhf+ by Hannah
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Well playing with Hannah’s HT a Yaesu VX-5 I can pick up the automated voice transmision from the control tower for Essendon Airport. It repeats itself, giving the time in UTC, with windspeed and direction, and temprature. The frequency that this transmits on is 119.8 MHz. Also been able to pick up flights coming into Melbourne Airport. Rather nifty, and kinda boring sometimes. 

In other news Hannah and I popped into Strictly Ham, in Bayswater, to have a look at some radios, I think we’ve decided that we will get the IC-7000.

~Ivy

Tags: musings, tech by Ivy
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Just looking at new radios Hannah and I may get, and we keep on looking at the IC-7000. This radio appears it will cover everything we want to do and more.

The good thing is we can easily set it’s output power so that on the foundation license I can transmit (there is a 10 watt maximum on the foundation license) and then ramp it up when Hannah goes to transmit (once we’ve transfered her license from the states to here.)

I really like the look and the feature set of this radio, and it appears it will work a lot better where we are, as it’s dsp filters should be able to cut out a lot of the noise.

Tags: musings by Ivy
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Well, got home tonight, and decided to do a quick scan of 80 and 40 meters as I do, got VK3LO nice and clear, discovered why, he seems to be only around the corner which would be why I’m able to pick him up quite well when he is transmitting.

So Hannah and I quickly threw up the wire dipole outside, and discovered that much to our dismay, we got the same results with the wire dipole inside (well it’s a different one, still about 10 meters per pole but up in the picture rail of our room.)

So the (electrical) sounds of the suburbs is still causing an issue.

What we really need to do is try and set up the wire dipole up a bit higher other than just throwing it up randomly in the back yard, and see if that makes any difference.

Or wait till next time we’re at mum and dads again and see what we can do there.

Or look at other antenna designs we can throw together in a cheap and easy manner, and see how they go.

All good fun.

Also saw the antenna tuner for the FT-707 on vk classifieds and by the time I’d got home the thing had sold, got to be a bit quicker.

~Ivy

Tags: musings, tech by Ivy
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Working with the radio at my mother and fathers place is much more successful than at home. The fact that it’s about 60KMs from the city helps. And it’s nice to spend a night in a place without light pollution is really nice.

Anyway Hannah and I set up a basic wire dipole antenna, 10 meters side to side, and strung it up around the decking out the back of my parents place.

This antenna cost us the grand cost of under $5AUD nice and cheap.

Anyway during the daylight hours, we listened in to the 20 and 40 meter bands, even picking up KE6M from california, which was kinda cool.

At night the 40 Meters seemed almost unusable as there was a lot of AM stuff emanating from China, and also a repeating noise that could of been an over the horizon radar system also from China.

But 80 Meters was fairly active, and we filled many pages of my little log book with stuff we found interesting. One of the cool things was a couple of guys talking about how to build decent chokes and baluns from stuff in their junk boxes.

A good day all in all.

I so need to get myself licensed so I can start transmitting.

~Ivy

Tags: musings, tech by Ivy
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Well to be honest I am new to the radio game. I do remember when I was ten or older a friend of my mum and dads was into ham radio. I thought this was amazing, I remember seeing the QSL cards that this person had, including one from East Germany and I really thought this was cool.

But in looking back, I think my interest began much earlier, with a radio receiver that my grandmother had. I can remember little of this set other than it was white, and had many knobs. The two things I do remember receiving on this radio, was the local constabulary talking about a stolen mini, and the Russian woodpecker. I found out what the “woodpecker” was from the show on the BBC many years ago “Tomorrows World”.

Anyway I digress, at home, in the near the City of Melbourne, with a basic wire dipole, I can pick up little other than noise, and faintly the odd voice, of which due to the noise I can’t make head of tails of.

I guess this is what one gets in world where cheap electronics spew out electrical noise. And possibly the trams running on their DC current also could be responsible.

Though to be honest, It could be all my electrical equipment in my room too.

In the end I guess I need a better antenna at home.

~Ivy

Tags: musings, tech by Ivy
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Well, I’ve been bitten by the radio bug it seems. Last week Hannah and I purchased a second hand Yaesu Ft-707 for not much.

It does have an issue with TX, which we haven’t really looked into yet (it could be a broken thermistor on the p.a. board) so we haven’t really tried that yet, which isn’t a big deal as I’m not licensed as of yet.

It does seem that the radio reception though at home is awful, though at my mum and dads place, we’ve been able to receive quite decently using a wire dipole antenna. We are restricted in what we can do at home mainly due to space requirements. Though I am interested in setting up the wire dipole out the back, to see if that could make any difference.

Our other aims are to see what other antennas we can construct and work from there, oh and get myself a vk3 call sign.

~Ivy

Tags: musings by Ivy
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