Ham Radio

Thursday, January 28, 2010
Home Brew 80m Delta Loop
click to enlarge image of Delta Loop

I have been so pleased with the 20M Delta loop I decided to scrap the dipole and have a go at home brewing an 80m Delta loop instead.

The result was well worth it as I found that the new loop antenna receives and transmits very well on 80M (resonant band), it also tunes up very easily on 160M & 40M, giving impressive results with very low noise levels.

The Delta loop is installed as seen in the above image with all of the dimensions included. I shall be posting more once I have had chance to test it further, I am really pleased so far and excited as usual, I'm looking forward to telling you more!
posted by Simon Davison @ 9:11 pm   4 comments
Sunday, January 24, 2010
Trans Match System For Loop Antenna's
I have been using my home made Delta Loop vertically polarized for the past couple of years with very good results. The Delta loop was made by myself with the intention of using it on 20M, I originally blogged about it here and since then, It has moved from the horizontal to like I said already a vertical configuration.

The horizontal testing of the loop brought slight noise levels where as the vertical triangle or pyramid configuration, is very quiet for noise and excellent on performance both RX and TX. The only issue I have had with the Delta loop was with my original calculations which proved to be slightly long, making it resonant on 13MHz instead of the desired 14.200 frequency. I cut the loop around two years ago and unfortunately made it too short as it was now resonant at 14.800 which was slightly higher than the intended frequency.

Subsequently I have been managing fine with the help of the ATU, but the burning feeling inside has been growing and niggling away as I have wanted the antenna to be perfectly resonant across 20M without any tuning. I had been chewing over various ideas that I have had and rather than replace the complete length I decided I had had enough guessing and needed to come up with some way of an easy adjustable matching system.

I thought about complicated tuning systems but in the end settled for some 3.2mm TIG welding wire, which I formed into a neat loop type hook on one end which connects to the dipole centre replacing the wire.I then slid the original wire up and down the 3.2mm TIG wire and secured the end with a terminal block as seen in the image.
Once I adjusted the overall length I got the SWR down to 1:1 /1:5 across the 20M band. I then fired up my plumbing blow torch and soldered the original delta loop wire to the added 3.2mm tig wire ensuring a excellent connection which would be permanent and WX proof.

The next image shows the feed point of the loop (dipole centre) with 3mm electrical wire (70ft long on Right hand side) and 3.2mm TIG wire (2ft long coming out of the Left hand side).
This image shows the movable trans matching system which once adjusted was soldered up outside to finish off the modification.
Hope this idea will be of use to some of you that are struggling tuning up any loop antennas. Now its time to try it out ATU free and see who is on the band.
posted by Simon Davison @ 4:13 pm   2 comments
Saturday, January 23, 2010
Tweaks and Tweets
The first Twitter Net was a lot of fun despite the 80M band being a little difficult for into G at the times that we have been running the net. However the Thursday Net still had plenty of us trying to get our signals back to each other with some nice QSOing had by all that made it in.
Unfortunately my first NET QSO was shorter than I anticipated as at the time there was around 3FT of snow covering my dipole ladder line, which after around 5Mins of TXing shorted out the feeder and caused a very high SWR reading back in the shack. I was forced to continue monitoring the Twitter Net in SWL mode but could still pass reports as “Tweets” to the #TWNET that were monitoring Twitter at the same time. Before the Snow shorted the feeder, Tomas OK4BX Tweeted that he could hear me in Czech Republic along side the other Stations that were also operating on the Twitter Net.
Tomas OK4BX kindly interfaced his Icom powered Shack with his web cam and streamed his side of the Net live over the internet which he shared with us all by linking the live video stream to the #TWNET Twitter page. This allowed all to see and hear how we were coming through on 80M in Czech Republic. Nice idea Tomas – Thanks!

Once the Net ended on 80M we decided to QSY to echolink where we all connected to a Repeater and managed to work a few more Stations that didn’t quite make it on 80M, it was fantastic to see so many Stations were keen to make it into the Twitter Net by any means necessary. Thanks goes to all who joined in!

We enjoyed the previous challenge so much that we decided to try it all again but at a different time which was early on Sunday morning at 10.00 utc. This proved to be a lot more successful for into G-Land.
I had been busy outside they day before installing a new feeding system to my 80M Dipole. I had decided I would try something slightly different from the open ladder line feeder and ended up fitting a balan at the dipole centre, fed with RG58 heavy coax which should keep out any water as well as other possible shorting problems with any luck. The performance has remained good and the Dipole seems to tune up well on 80M right through to 10M, I can also get it to tune down on 160M which was previously not possible with the ladder line fed Dipole.

The Dipole worked well for me during the Net and has continued to perform well on 80M and 40M throughout the week, with some good reports from N.America being obtained. I also got into Cuba with the Dipole down on 40M which was another good report for the humble antenna. I may consider changing the flat top configuration for an inverted Vee set up just to see how the performance differs in the coming week if I get some spare time.

At present my HF antennas consist of an 80M Dipole, 20M Delta Loop and the Hustler 6BTV which I’m pleased to report are all still doing a good job for me as well as giving me a varied pattern of reflected and radiated signal patterns across the bands. This choice of switching between the antennas is proving to be a very advantageous luxury, as the difference in noise, signal quality and strength varies between them all dependent on the time of day and band/conditions. The change in the height of the Ionospheric layer are responsible for this and are noticeable with each of the antennas when the switching of horizontally and vertically polarized signals is carried out, often with massive differences taking place of up to 20db.Dependent on the time of day I have found that all three antenna’s out perform each other with no one antenna being the overall best.

I should be back on 80M with the Twitter Net Sunday mornings at 10.00 utc and again on Thursdays at 20.00 utc.
So far, we still haven’t managed to arrange anything for the other bands such as 20m and 40m.
I am interested to see if we can work some of our State-side and European friends that have been in touch already on Twitter confirming their interest in trying to make the QSO. I hope to it make soon Guys!

As well as all this twittering on, you can see I have been playing quite a bit of radio across the bands already this year and I aim to continue my radio antics more than ever.
Check out the graph by clicking on it to enlarge. The graph shows where on the bands I have been active this month so far.


Thanks for visiting 73.
posted by Simon Davison @ 11:39 pm   2 comments
Tuesday, January 12, 2010
80m Twitter Ham Net LESS Than 24HRs
Lots of interest has been shown so far on Twitter regarding the 1st ever 80m Twitter Ham Net, which will be held tomorrow (Wednesday 13th January) at 20.00 UTC.
Since the idea was suggested there has been a lot of Hams tweeting messages and leaving comments confirming that they will be by their Ham Radio Stations and at the same time be on Twitter tomorrow night. I can’t believe how well you have all responded from as far as The USA, to Czech Republic and the UK alike, there is a lot of enthusiastic Tweeting Hams out there!

The easiest way to join in is by getting on Twitter, create an account and either follow somebody or just search for other Hams to follow such as myself, example @2E0HTS. Once you find us all, you will easily see what were up to and which Hams are operating as well as any SWLs. All are welcome. :-)

Useful info for Twitter Ham Net Ops

- All updates can easily be searched for by using the trending topic #TWNET

- Tomorrow Nights NET - 80M. Actual Frequency will be posted at 19.55 UTC. This can be found by searching for #TWNET

Hopefully we shall have lots of fun and create some activity on 80M. If successful we could try different Bands at different Times, allowing Hams from all over the world a chance to mix Ham Radio and a bit of Internet Tweeting together to make some great QSOs.
It should be a good Net, I and many others are getting excited with less than 24 hours before the Twitter Ham Net takes to the Air for the very first time. We all Hope to hear you and be heard on the Twitter Ham 80m Net tomorrow at 20.00 UTC. It should be a great turnout, see you there!
Thank You to Everyone who is involved so far, keep up the great enthusiasm Tweeple! ;-)
posted by Simon Davison @ 8:23 pm   3 comments
Sunday, January 10, 2010
Twitter Ham Radio NET On 80M
Over the last few months I have been slowly building up my list of interesting Twitter users to follow and be followed by. This has helped to take the mind off the WX (which of course is still snowing) by enjoying some Tweeting over the internet. Most of the Twitter Folks I follow are Either HAMs, SWLs or people involved in radio and they are all full of interesting Tweets which I have enjoyed a lot.

Since new friendships are beginning to form via Twitter, We have all decided to try out, a planned radio sched on 80M this coming Wednesday evening at 20.00 UTC. We will use twitter to relay the frequency on the night at 20.00 UTC as well as any reports from SWLs and anyone struggling to get back to NET.

So far there has been 7 Stations that have confirmed that they will be on the Air at 20.00 UTC (Wednesday 13th) and as we only decided two hours ago we are off to a fine start. There will be regular updates on Twitter regarding which Stations will be active and on the night as well as displaying the frequency used. If you want to know more about the kind of stuff we Hams get up to in an informal way, check us out on Twitter. Hope to hear you on the 80M Net Wednesday Night.
posted by Simon Davison @ 10:44 pm   10 comments
Wednesday, January 06, 2010
The New Year Continues To Test Us All
The New Year is proving to be a challenging one so far for many of us across the Globe. Here at Baildon Moor, Yorkshire we have been suffering now for almost 3 weeks with no sign of improvement. At present the temperature has dropped down to -2.5°C which isn't helping much regarding the frozen pipework that is preventing the use of the kitchen sink and shower.
We have been visiting the Family on a regular basis where hot food and the use of the shower is available, but to be honest it has been really hard going.

The upside was a chance to play on my new Yaesu FT-817 at a different location using the Miracle Whip and 5 Humble Watts. It wasn't long before I got my first long distant QRP contact on 20m, which was Andy - EW6GF from Belarus.
The QRP rig worked very well for me and back at the QTH, I decided to try the little FT-817 with the Hustler 6BTV.
The mighty Hustler Vertical and 5Watts began to impress me as I continued having QRP fun working as far as The US thanks to K3C, K3LP and W1AW, all worked and logged.

I also got lucky on the Amateur Satellites as I made it into Canada - VO1ONE, via AO-51 using the Yaesu FT-847 and the home made IO-TEN EL Sat antenna.
The Satellite DX didn't stop there, as I managed to get into the new Chinese SAT XW-1 which is now known as HO-68.
The new SAT has a fantastic footprint which allowed me to make it across the Atlantic into FN34JK, where Daniel - KB1RVT came back to my Call via the new SAT.
I have had plenty of other excellent QSO's via SO-50, AO-51, VO-52 and the new HO68 into Europe over the past couple of weeks, thoroughly enjoying the whole affair.
I'm looking forward to meeting some more of you soon via the Sats in 2010.

Back to the WX. With the snow coming down thick and fast I battled into work yesterday in the excellent snow munching Toyota RAV-4, (full time 4 X 4) only to find that the College where I work was closed due to the bad WX.
This was a another great opportunity to forget about the WX for a while and get on the bands during my usual working time.

I made some nice QSO up and down G-Land on 40M working some interesting Stations such as M0CNU - Tom, from Falmouth and Ivan - G4WIA, who was near by to Helston. Both Stations were very strong on my FT-767GX which is fed into a 130ft Dipole pointing North/South.
I enjoyed some lengthy conversation from the County of Cornwall from both Stations which was very nice, as we had visited their region only last Summer when we went to the Marconi Centre.
So you could say every cloud has in this case a Snowy lining, but at least I got the day off work and played some radio.
I was back in work today with a slightly earlier finish and as you can see from the pictures of my 20M Delta Loop and Hustler 6BTV any more Snow could cause a bit more fuss and trouble!

If we all think warm thoughts hopefully the pipework will thaw and we can get back to normality, but in the meantime its slow safe driving and plenty of thermals. Not forgetting as much RF as I can possibly generate, Micro waves preferably! 73 Stay warm and safe.
posted by Simon Davison @ 4:58 pm   5 comments
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