Friday, December 28, 2018

Getting Started with Digital Modes (WSPR)

Weak Signal Propagation Reporter


Discovering digital modes for the first time, I found WSPR is a great mode to start with as you can simply start listening for and decoding beacons right away, and have your mind blown at how far away these weak signals can be received when you cant hear anything audibly out of the speaker!

This doesn't cover how to configure the software and radio. There are plenty of guides and docs around on how to get WSJT-X communicating with your rig.

My hope is to capture enough data from the WSPRnet.org database to start building a picture of how well my station transmits and receives signals on HF compared to others by looking at distance per watt stats etc.



I have spotted ZS3D several times over the last few days on 40m at a distance of 16, 233km / 10, 087 miles, and today ZS1OA on 30m, slightly further at 16, 511 km / 10, 259 miles! These stations are probably about as close as I'll get to hearing something from my antipode.



A surprise when I spotted beacons from stations on 630m (472kHz) in Northern California and BC!

After a few email exchanges with Joe NU6O, I learned that 630m propagates best with vertical polarization. Joe is using a 43ft vertical near salt water, 100W transmit power to radiate 1W EiRP [Antenna is 1% efficient], his beacons are regularly decoded in Japan across the Pacific.

I'm only spotting stations nearby on 630m because I'm using a Carolina Windom 80, less than ideal for this band being a horizontal wire with out any matching / loading for 630m, its kinda surprising I heard anything at all.

WSPR can also be used to indicate the possibility of using other modes based on the reported SNR, see https://www.qsl.net/kp4md/wsprmodes.htm

Update Jan 03 2019:

Transmitting beacons yesterday..



Heard by DP0GVN in Antarctica on 30m [10Mhz]!



Heard by ZL3003SWL in New Zealand on 15m [21MHz]!

A couple of other surprises transmitting a few beacons using 50W at one point on 12m [24.9MHz] and 10m [28MHz], I was heard in California when you'd think these bands were otherwise completely closed for voice modes.

Saturday, December 1, 2018

Back to Radio

After around 10 years away from the hobby due to travel, marriage, children, moving a few times, and finally buying a house, I made the [fatal] mistake of looking at Icom's website and seeing the IC-7300 on there, and before I knew it I had ordered one along with a bunch of other stuff.



As always, things start simple, a couple of rigs on a folding table in the spare room.

My current station consists of:

Icom IC-7300, bang for buck these are amazing, I don't need to repeat the dozens of reviews that can be found.

Carolina Windom 80 at 40ft, I've built and used OCFDs before, they are simple and work well for what they are. The Carolina Windom I bought from the man him self. I'm not entirely convinced the vertical radiator does much useful other than pick up vertically polarized noise, I cant find any detailed models / radiation patterns online, no one seems to have done any, or put them online.

LDG RT-600 Remote ATU, not entirely impressed with this, the internal tuner in the 7300 does a better job sometimes, I was offered the weak excuse of the coax losses absorbing some of the reflected power and thus giving the internal tuner an easier match. Um wait a minute, the RT-600 is intended to be at the antenna end, and should be-able to handle this. And sure if I was using 200 ft of RG-58 thats going to help a shack tuner, but I'm using 100ft of LMR-400, which is so lossless on HF it shouldn't make a difference what end of the coax the tuner is on. More experimentation needed.

Kenwood TM-731A - I already had this, in-fact I brought it with me from New Zealand. I love these older dualbanders with ham band only receivers, this makes the front ends nice and robust against intermod - desirable when you're mobile in todays RF filled environments.

Alinco DR-135 - IRLP node 7441, I built this in 2015.
Comet GP-15 - Shared by IC-7300 on 6m, DR-135 on 2m, and TM-731A on 70cm via a tri-plexer.
Kenwood TH-D72A - 2m/70cm - APRS (sometimes), Christmas present from my wife in 2012.

First time I have had a station setup in populated area, and the noise on HF is a real pain, its safe to say I have been spoilt with very quiet locations in the past when I was active on HF! After smashing in a good grounding rod at the remote ATU for the Windom, and installing clamp on ferrites around the feedlines where they enter the shack, this made a vast improvement. I suspect there is a dodgy powerline insulator or transformer nearby, as I get power line type fizz noise, even up into the VHF bands!

A quick run down of the past:

2018 - Back on HF with an IC-7300, Carolina Windom at 40ft.
2014 - Moved to Puyallup WA [35 miles south of Seattle].
2013 - Built IRLP Node 7441, started on a 70cm HT, rebuilt in 2015 with Alinco DR-135.
2012 - Licensed as KL3NO in Fairbanks Alaska, active on 2m/70cm mobile.
2012 - Moved to Fairbanks Alaska.
2011 - Back in NZ.
2010 - Spent a year in Canada - Revelstoke BC and Golden BC on working holiday visa.
2008 - Built IRLP Node 6095.
2008 - On HF with a Kenwood TS-830S, and Icom IC-746 Pro.
2006 - Licensed as ZL1SAT.
2004 - Spent a year in London UK on working holiday visa.
1998 - Interest in ham radio fizzled out, and I sold the last rig I had - Kenwood TR-9130 2m all mode.
1993 - Licensed as ZL1TNI, active on 2m and 70cm FM, SSB and occasionally RS Satellites [2m up/10m down], I see these are all defunct now - they were a ton of fun!
1990 - The radio bug bites, discovered CB radio, much fun was had on 11m/26MHz during the end of solar cycle 22.