SOTA Activation – VK7/SC-052

View east towards Tasman Peninsula and Iron Pot

View east towards Tasman Peninsula and Iron Pot


On Saturday the 11th of October 2014 I undertook my first SOTA activation and the first activation for VK7/SC-052 – Tinderbox Hills. It was a rushed affair with work and family meaning I was not properly prepared come Saturday morning. But after an initial stumbling block (15 minutes into my walk, realising I’d left my batteries at home) I did successfully activate the summit.

The summit is easily accessible via a good track maintained by Kingborough Council. With both easy parking found at the end of Estuary Drive, and then a clearly signposted start of the track. And as per the sign, it’s a ‘moderate’ walk taking at most 45 minutes to get to the top.

Start point (car park) for VK/SC-052.

Start point (car park) for VK/SC-052.

Along the way you’re presented with rather nice views both east and west – as after all, you’re walking along the single ridgeline of a peinsula. To the west you look down over Northwest Bay to Margate, and out to the east you can clearly see Iron Pot, Opossum Bay and onto Tasman Peninsula – and also clear to New Zealand (but obviously not visible). And if you look back down the track you can see Mt. Wellington rising above the tree line.

Overview of the walk for VK/SC-052.

Overview of the walk for VK/SC-052.

There are a couple of rocky areas and some step bits to keep the heart moving, however I did see two ladies arrive at the top after me arrive on mountain bikes.

Of note though – and something readily seen on the maps from LIST map – is that the summit is actually on private land. This is further emphasised by signs from the Council as there is no fence line. However, the boundary is between about 10 to 15 meters vertically of the summit, and luckily SOTA rules are that you must be within 25 meters of the summit (vertically). And better yet, the sign-post provided for a reasonable support for my squid pole extend and 2m half-wave dipole attached.

(The boundary line can be seen as the grey line intersecting the close up map on the right.)

Map showing set-up location right on the private boundary line - noting the summit of VK/SC-052 is actually on private land.

Map showing set-up location right on the private boundary line – noting the summit of VK/SC-052 is actually on private land.

My plans for the day were to activate on 2m FM, 2m SSB and 40m SSB. As it was, on 2m I only made three contacts (not enough for an activation), so lucky 40m than filled in the remainder by providing 18 contacts.

A resulting rough breakdown for 40m:

  • VK7 x 2 (however, I think neither had heard of SOTA so I’m not sure they’ll be logged)
  • VK2 x 2
  • VK5 x 1 – as a S2S (and obviously my first for that, and his – VK5CZ – to a VK7 summit)
  • VK3 x 13

I’m hoping that in future I might have more success on 2m – especially some SSB – but I think I’ll need to make sure I attempt to make more locals aware of the activation. Indeed, I would love to be able to activate some of the local peaks (Mt. Wellington – VK7/SC-001 and Mt. Rumney – VK7/SC-045) with nothing but 2m. But we’ll have to see what can be done.

But that all said, a fun time was had and some lessons were learn’t – such as, I carried far more battery power than I needed, and seeing they were two 4Ah SLABs, it would’ve been great to have taken only one. And I’m definitely looking to get organised and get another activation happening soon!

Thanks to everyone who took the time to reply to the calls. 🙂


RTL-2832 and Raspberry Pi for ARPT and FUNcube

RTL-2832 and Raspberry Pi for ARPT and FUNcube

Last year I was playing with a cheap USB dongle for weather satellite reception. Eventually though I gave up on it, as although I could receive reasonable pictures with it, the device kept causing my machine to freeze.

Anyway, I recently dropped a raspberry Pi in the shack to act as a router between my shack and my wireless network. It got me wondering as to the possibilities of running the dongle via it. Turns out, it was as easy as… pi! (Sorry… 🙂 )

It really only takes a few simple steps:

  1. Download the rtl tools source code via git from OsmoSDR
  2. Build up the tools (make sure you’ve installed the build-tools package on your pi)
  3. Make sure you unload an DVB kernel modules with rmmod (after checking with lsmod)
  4. Run rtl-tcp on the raspberry pi
  5. And then connect via TCP from something like SDRSharp

Doing this I’ve had no problems with anything freezing, and have captured images with as much ease as I did before – although I have a dodgy coax cable I need to fix.

Further, I’ve gone on to receive beacons (6m, 2m and 70cm) as well as the FUNcube telemetry. Actually, to my surprise I’m the only VK7 to have recorded reception of any telemetry (according to the FUNcube Upload Ranking page).

To finish, here’s a couple of images received via this setup (one from NOAA-15 and one from NOAA-19). And the title picture of New Zealand is from NOAA-19.

NOAA-19 Received

As mentioned in my previous post, now that I’ve got my 2m/70cm setup in place, I thought I’d try some Weather Satellite reception again. Sure the antenna is not ideal (it’s neither tuned for that band – 137MHz – nor is it circular polarised) and sure the radio is not ideal (recommended IF is 30kHz to accomodate doppler shift etc.) but you’ve got to try.

My previous attempts were in Canberra with more or less the same gear – albeit a different computer which only had a standard AC’97 inbuilt (current computer has an Audigy 4). But that location was with a temporary low install of the antenna that had many blocking objects. So I was hoping the new location with far greater access to the sky would see better results.

NOAA-19 0404UTC

NOAA-19 0404UTC

Last night I quickly downloaded WxToImg onto the machine and went about dialing it all in – making sure the audio was all correct as I’d have to leave it to run over night while I slept. I settled on NOAA-19 as it looked to have the best passes over the coming period.

Checking the images this morning, there was nothing too spectacular, however there was a good predicted pass for this afternoon just after 2pm (local time). So I waited the day with keen anticipation to see what would occur.

Checking the image just after 2pm, I was amazed with what I could see. The resultant image even as a thumbnail was far better than anything I’d ever achieved in Canberra – and that is what you see in the first image. I didn’t expect anything with such detail and colour unless I got a better receiver (and most likely a proper antenna).

But it was a good pass, and indeed with such good clean sky access I believe it helped. The interferance that did result I believe was down mainly to fading due to circular polarisation and also the bad weather we were having (heavy cloud and rain – indeed, you notice in the image you can not make out Tassie other than for the computer generate outline). Here are the details from WxToImg of the predicted pass:

2013-07-02 UTC
Satellite Dir MEL Long Local Time UTC Time Duration Freq
NOAA 19N 71E 150E 07-02 14:04:18 04:04:18 11:54 137.1000

As you can see, a nice high elevation (71 degrees) and a good long duration.

Also, for those who have not played with this before, here is the combination image that is received and then later processed to generate the multitude of other formats (the land mass outlines and lat/long grid are added in WxToImg):

NOAA-19 0404UTC - Full Image

NOAA-19 0404UTC – Full Image

And so that you have a comparison, following is the pass prediction and image (same format) that I received just before 2am this morning – which left me wondering if there was any hope. But note the lower elevation and the fact it is to the West – which is where the land slopes up and away from me, so really the pass would have been much shorter in duration.

2013-07-01 UTC
Satellite Dir MEL Long Local Time UTC Time Duration Freq
NOAA 19S 49W 140E 07-02 01:42:59 15:42:59 11:43 137.1000
NOAA-19 1542UTC - Not so flash

NOAA-19 1542UTC – Not so flash

I’ve still got the setup in place and am looking forward to another four more passes before tomorrow night (two to the East, two to the West) which will provide for some interesting comparisons.

Unfortunately I have no CAT cable, otherwise I could have WxToImg automatically change frequency and attempt to grab the other two satellites as well. One day.. maybe..


2m/70cm Antenna Installed

It’s been a bit quiet lately due to life and the many surprises it can bring. However this week-end I was finally able to get my first permanent antenna install complete.

X-50NThe antenna I installed is my dual band (2m/70cm) antenna that I purchased a few years back with the hope that one day it would become my permanent base station antenna. It’s a Diamond X-50N and when I’ve used it in the past I’ve been very happy with it’s construction and performance.

Stats taken from the Diamond Antenna site.

Stats taken from the Diamond Antenna site.

Not long after moving to my new QTH I rushed down to the hardware store and grabbed the fascia mount TV support and bolts and then was keen to get it installed. However, first I wanted to get the access panel done and then realised I needed a bigger ladder – as the install location is essentially two stories up (the antenna is now sitting ~6m above ground).

Anyway, a hire company came to the rescue and all worked out well this week-end. And with the access panel in place, it sure made the cabling very straight forward. Although, I do have a goal of eventually having some semi rigid cable for this, but for now RG-58C/U is doing the job (albeit I should only be losing about 2dB and 4dB, and this is really only for local simplex and repeater work).

I’ve only had one contact with it so far, but that was as a result of the first (and only) CQ I put out on 146.500. Reports were good from over in Bellerieve (5/7 – loud and clear) and I can happily trigger all the local repeaters on 2m, and I only attempted one on 70cm – need to try more. So, it seems a good result and I look forward to trying it out more soon. (Plus, I’m going to try some WX Satellite reception here – though on Windows this time – and see how it goes compared to my efforts in VK1 – although it still will be a sub-optimal antenna and receiver for that).


Amplifiers for 2m

My main (only) radio for 2m SSB is my FT-817ND. Putting out a whopping 5W, I do hope that one day I can look at a bit more power. To that end, I’ve always intended a linear amplifier. Nothing huge to start with, just something getting me say 25W or more – maybe 50W.

Recently I came across an Italian company that appears to produce some cheap units that may be suitable. They have a VHF range that can be seen here.

Reviews seem to be what you’d expect for in that price range, so maybe it’s an option. However, that got me thinking it’d be great to build my own when I get to that point. So I started looking to see what was around.

First, I knew Mini Kits had some options such as the RA VHF Amplifier Kit. In general though, there doesn’t seem to be that many kits. So I thought I’d also look for some plans.

First was one that looks kind of achievable. Using a single high power transistor for about 100W output was the OZ2OE 144MHz PA with MRF317.

But from there only a couple of other options were really found (on a very brief search), but the top end was a kW amplifier with dual valves – the LA0BY 144 MHz high power amplifier for 2 x 4CX250B.

Anyway, that’s a ways off for now. Have a few other things to get going first – finalising my new home setup for starters (more pics of that soon).