Friday, 31 October 2014

HB9CV without capacitor experiment

This post was actually written 2 weeks ago. But things happen so fast here I could not publish it before.

Although I have some experience in building HB9CVs for 11m I didn't manage to build one which completely satisfy me in terms of simplicity, mechanics, bandwidth and SWR. Long time ago I came across a HB9CV design that worked without a capacitor to match the impedance. That means this antenna would be simple and manage unlimited power. I was already planning to rebuild the HB9CV built last year. I made another construction and designed it for 28MHz flat instead of 28,5MHz. In this design the "gammamatch" ,if you can call it like that,  is 2 times longer as the original design, that will say the distance between the boom and were it is mounted on the radiators.

Not trusting designs like this I didn't expect it would properly work but it does actually. SWR at the original design I found was 1:1,4 R=43 X=7. Not bad at all, SWR stays below 1:2 between 27,5 and 28,5 MHz. So I made the elements all 1cm shorter and now the resonance shifted to 28,1 MHz. Since I made the "gammamatch" so it could slide over the radiators I tested if the distance between the mounting point and the boom should be longer or shorter. Till now making it longer giving me a best SWR of 1:1,2 R=45 and X=7. Not bad but of course  I would like to try for 1:1 or at least as close to that as possible, however SWR is not the holy grail. What I was afraid of is how it would affect the radiation pattern. But walking around the antenna with the fieldstrength meter and the whip horizontal shows a max. in the front and a complete nul on the backside. It seems that it doesn't matter were you connect the "gammamatch" as long is you keep the relation in distances.

2 things to do. I'm not satisfied about the connection between the boom and the elements. I have to change it a bit. And making the "gammamatch" wires a little longer to see if I can get a even better match.
This experiment has potential and I hope to get a fine working antenna out of it.

Related links on this blog:

The HB9CV revisited 1
The HB9CV revisited 2
Progress building the HB9CV
HB9CV test



Thursday, 30 October 2014

Antenna hints

Something I was searching for when building antennas is the difference between resonance and impedance. Really, I've learned it when I did my radio exams but when you learn a lot you also forget a lot. So a future reference for myself and others:

R=resistive load, X=reactance

1.) RESONANT FREQUENCY is where reactance is zero ohms, or in some cases as close to zero ohms. Since resistance has nothing to do with resonance, the resonant frequency is NOT
always at the point of lowest indicated SWR (although they certainly can be the same). The most desirable load is almost always the load with lowest SWR, even though it may not necessarily be the point of no reactance (resonance).

2.) An IMPEDANCE of 50 ohms can be composed both resistive and reactive components. If the impedance is 50 ohms, but the SWR is not 1.0 to 1, the likely cause is reactance makes up part or all of the impedance. Contrary to popular (but very incorrect) misconceptions, it is impossible to obtain a perfect 1 : 1 SWR when the load is reactive, even if the complex impedance is 50 ohms.
A good example is a 50 ohm nearly pure reactance load. R=0 X=50, while the impedance meter reads 50 ohms. The SWR would overflow (SWR>25), since the reactive 50 ohm impedance load absorbs almost no power from the source and has a nearly infinite SWR.

3.) Even if a perfect transmission line is cut to an exact electrical half-wave (or a multiple thereof ) it is a true half-wave multiple only on one frequency in that band. On a slightly different frequency the line will not represent the true feedpoint impedance of the antenna. The line is only “impedance transparent” when lossless and when an exact multiple of 1/2 wl. The longer the transmission line in wavelengths, the “more length critical” it becomes and the less accurate measurements become.

4.) If the feedline is not an exact multiple of 1/4 wl, the resonant frequency of the antenna might be shifted higher or lower by the transmission line. A mismatched non-quarter wave multiple feedline adds reactance that can cancel antenna reactance at frequencies where the antenna is not resonant. Multiple antenna and feedline combination resonances commonly occur with dipoles, where reactance crosses zero (indicating resonance) at some frequency other than the antenna’s actual resonant frequency. This is a normal effect.

5.) If the line is a 50 ohm line, has no radiation or parallel currents, and if the line has minimal loss, moving a analyzer to another point on the line will NOT change SWR reading. Impedance and resonant frequency might change from line transformation effects, but the SWR will not change.

6.) If SWR changes with coaxial line length, line placement, or line grounding (any distance away from the antenna) changes, the feedline has one or more of the following shortfalls:
 a.) The feedline is carrying common mode current and radiating.
 b.) The feedline is not a 50 ohm line.
 c.) The feedline has high loss.

We have a clubmeeting tomorrow evening. PA0HPG Harm is going to talk about using a FA-VA3 antenna analyzer and how it helps to make your antennas work. I really like this kind of talks and hope to learn a lot from it. If it reveals something important I will certainly update this post or post a new one about it.


Wednesday, 29 October 2014

CQWW DX SSB 2014 last weekend

Event: CQWW DX SSB ham radio contest
Logger: N1MM+ most updated version
Station: Icom IC-706MKIIG 100W, headset&Turner+3B combined
Antenna: Homemade aluminium tape all band HF vertical with CG3000 autotuner at 9m AGL.
Coax: 50m Belden H1007


JV5A on his morin-khuur, worked 40m
In my eyes this is the biggest SSB contest of them all with the best and rarest DX. If you are a serious DXer you really should participate in this contest even if you never participate contests at all. The propagation was surprisingly good. Although there seemed to be a radio blackout Saturday at 17:00 UTC I didn't experience it as I was not on the radio at that moment. At the hours that I was on the air conditions were great. I started very early before work (3:45 UTC) Saturday morning on 160m and first QSO was with PI4M, Frank PF5T was on the mike and told me he had read my blog about the CQWW wishlist. That was fun! Had to stop at 5 UTC with 60 QSOs in the log, not bad for a hour S&P! I returned Saturday evening at 21 UTC and made as many QSOs as possible including some nice DX like JV5A Mongolia, 9K2HN Kuwait, UP2L Kazakhstan and lots of Canada/USA all on 40m.

I was up early again Sundaymorning and started to work 80 and 40. Lot's of USA and easy to work too. When sunrise was approaching I checked the higher bands regulary. A half hour before sunrise 10m came to live and I easily worked the middle east. My first new DXCC of this contest with S79K was worked with some difficulty at 5:54 UTC and at that time it was still dark (sunrise 6:18). Working DX on 10m with the vertical is not easy but can be done. 10m and 15m were wide open now and I managed to work another station from my wishlist AH0K from the Marianas. Had to stop around lunchtime and returned in the evening when 15m was absolutely crowded with USA/Canada all very easy to work.

Most interesting DX: 

80m: K3LR and lots of other USA, UP2L Kazakhstan
40m: K3LR and lots of other USA, 8P5A Barbados, JV5A Mongolia, UP2L Kazakhstan, 9K2HN Kuwait, VY2RX and more Canadians, P40L Aruba, FM5EB Martinique, WP3C Puerto Rico, HK1NA Colombia, A73A Quatar
20m: K3LR and lots of USA, VY2TT and lots of Canada, HI3TEJ Dominican rep., YV4NN Venezuela, 9Y4W Trinidad and Tobago, KP2M US Virgin Isl.
15m: A73A Quatar, KL7RA Alaska, K3LR need I write more?, VC2T and more from Canada, HK1NA Colombia, KP3Z Puerto Rico, PJ4DX Bonaire
10m: A92GE Bahrain, A61ZX UAE, A71CO Quatar, S79K Seychelles, ZD8X Ascension Isl., JA0FIL Japan, A73A Quatar, HZ1TL Saudi Arabia, VU2RBI India, AH0K Mariana Isl. and of course USA in the morning already, but no Canada.

More stats: 

Participated time: 12 hours, QSOs: 523, CQ zones: 24, DXCC: 78

DXCC map as generated by QSCOPE

Logger

N1MM+ was tested on SSB this time. Configured with my IC-706 in SO2V (Single Operator 2 VFO). The program still didn't work flawlessly. I did need to configure the IC-706 CAT com for 4800bd otherwise connection would be lost in a minute. After that I had to restart the program every hour or so because of the slow CAT connection. It looks like the CAT had a overflow of info, especially jumping in the band map from one station to another with CTRL+up/down. At one time the program had a stack overflow error screen popping up and tried to e-mail the error. Unfortenately for the programmers I have no e-mail configured so the report could not be sent. It would be better to create a file which you can manually attach to an e-mail so it can be send later. However overall I like the new N1MM+ contestlogger a lot.

In general

Great propagation this contest. A lot of participation from rare DXCC. I had limited time but still worked over 500 QSOs and even worked 2 ATNOs. What strikes me sometimes is the ability of receiving or listening from some stations. For example C37NL was heard on all bands, but no QSO. It seems they had problems receiving as I heard many others calling without succes. On the other hand S79K must have amazing ears to catch my tiny signal, I could barely hear him so that had to be the same for him. I didn't stick too long at stations that couldn't hear me, calling 3-5 times and still not being heard is moving to the next one. And...yes, it was a fun contest.

Bloggers worked

Worked OQ5O Franki on 80m, PA0O Jaap on 40m. Some other known non-blogging operators as well.

Zone chart thanks to 2E0HTS Simon


No time & internet

You all probabely think what happened with Bas. Did he participate in the CQWW? What is he doing? Why is he not updating his blog?



Well, things sometimes happening faster then I can write and not like planned. I have no time to update the blog. But I am radioactive (see my list of ATNOs at the right). Besides that we have a large internet interruption in my village, no internet for the time being. So expect some posts but have patience.


Sunday, 26 October 2014

G4ILO

http://onefootingrave.blogspot.co.uk/

Julian G4ILO was a great inspiration for us all. It's a big loss for everyone that knows him. We will miss him. It was great to meet him on air in the past. Rest in peace Julian.


Wednesday, 22 October 2014

CQWW SSB 2014 (ATNO) wishlist

Like every big contest I have a wishlist. This CQWW SSB there are a lot of DXCC that are on my wishlist. Unfortenately for the radio hobby next weekend will be a busy (work, family etc.) one, I got only a few hours to spend so I will do my best. I had a day off today as my XYL had to go elsewhere. So my harmonic Anneli and me were at home. She was at school in the morning and that gave me time to finally work some DX and resulted in a ATNO on 17m and 20m with Lord Howe Isl. VK9DLX. I managed to work ZM90DX in New Zealand as well on 17m which was a new one on that band. 10m was open today and Christmas Isl. VK9XSP was crystal clear 5/9 here on the vertical. The pile up was huge unfortenately. Anneli wanted to wear the headset for the first time and called "one two, one two", seems she saw it on TV or so? Didn't let her TX for real of course. But she knew what the problem was telling me that "they" didn't hear her and it had "no use". So we went on playing with lego blocks then. I did call VK9XSP about 20 times before that, but I think I have to wait till the end of the DXpedition or have a chance at the CQWW contest this weekend hopefully. My list of wished ATNOs extracted from the excellent NG3K list.

4W/K7CO Timor Leste
5W0 (3 stations!) Samoa
AH0K, NH0DX Mariana Isl.
KH8B American Samoa
S0S (no emergency, what a strange callsign!) Western Sahara
T88 (2 stations) Palau
TO0X Mayotte Isl.
TX7G Marquesas Isl.
VK9XSP Christmas Isl.
XX9R Macau



Friday, 17 October 2014

Big machine

I guess most of us played with model trains in our youth. I have to admit I sold my Märklin HO model train last year after sitting useless in a box the last 25 years. This morning our view out of the workshop was a big machine on rails that repairs railways. As always I'm interested in this kind of machinery. A small search on Google reveals a lot.


Spitzke 09-3X specs
Spitzke 09-3X photos



It was fun to see how many times people made photos from this special train. I guess it will show up in some local news paper articles next week.

Just before I sold my model train a test and a small video was made to remember good old times!








Wednesday, 15 October 2014

Comparisation aluminium tape vertical & 3 band endfed

Since I got very good results with the PE1BVQ 3 band endfed on my 12m glasfiber mast and using the Yaesu FT-817 I was curious which antenna would perform better. I would like to know how my homemade aluminium tape vertical would perform in comparisation with the simple 3 band endfed.

This experiment takes only half a hour so I made a quick setup just before sunset. I setup the endfed on the 12m glasfiber mast with the matching box on 2 mtr above the ground, the antenna was connected to the radio with 20m aircell7. The alu tape vertical is mounted with the autotuner on 9 Mtr above the ground and has 3 radials. The results are shown in the video. Almost no difference except on 40m were my alu tape vertical seemed to be better. I spoke about it with PE1BVQ Hans, he thought it could be the coil that is placed for the 40m band extension wire. But I think, since the signal came from Europe, that the endfed has a lower radiation angle. Over all I had the idea my alu tape vertical was slightly better and certainly has less noise. Although on 20m it picked up some rattling noise that could not be heard with the endfed. If the endfed was mounted at a 9 Mtr mast I guess it would perform equally or better as my Alu tape vertical. I was not the only one making a test, someone else did post a video comparing a vertical and a endfed here. Although it is not clear what the setup was of the vertical.


Speaking about my alu tape vertical, just searching on google revealed something interesting. There seems to be more then 2 (Alu tape/Copper tape) conducting adhesives. Most interesting is the 3M Z Axis Tape. The adhesive is filled with silver coated nickel particles and is extremely conductive. It is double sided but that doesn't matter for a antenna as you always cover it with other tape as well. The interesting thing is that the adhesive is conducting and not the tape itself, so wrapping around is no problem. With aluminium tape you have to use long strokes as the adhesive as not conducting. I think it would perform extremely well on a antenna, there is only one big disadvantage and that is the price. You can buy 33 Mtr 25mm tape at Farnell for €181,45. That's a lot of money for a experiment!

Monday, 6 October 2014

Some CQ, some DX...

Had a day off work today and managed to do some radio in the morning. Wandering over the bands discovered the propagation was real good on the high bands. I answered a call from JA2FTR and he reported a 5/7. Not bad, although he was using a 7 element yagi. I was confident enough now to call CQ on 12m and after some russian stations responding I heard a very weak reply from a station with "4" in the call. Had to ask him 2 times before I got the call, it was Markus 5Z4/DJ4EL from Lamu Isl. (AF-040) in Kenya. Wow, not a ATNO but a first time on 12m and he came back on my CQ. 

I had to do some other things and went to WSPR 10m with 1W. Worldwide results today...The map shows TX and RX. I was received by 39 different stations, best DX was ZL1RS (17750km).



I still hope for a spot from T5/T61AA, he seems to be active on 40m at night. But when you look at what he receives it is not much. I guess he has too much interference nearby.

Sunday, 5 October 2014

Signal strength differences between JT65 software


I had a little argument about how JT65-HF and WSJT-X receives. Paul PC4T thinks the JT65-HF HB9HQX version decodes better as WSJT-X. Hans PE1BVQ writes me via e-mail JT65-HF original (last) version decodes better as JT65-HF HB9HQX and returned to WSJT-X 1.3. Now, actually the original JT65-HF version will not be updated and I left it out at the test. I downloaded and installed the newest versions from WSJT-X, JT65-HF HB9HQX and JT65-HF Comfort. WSJT-X was set on JT65 decoding only, both JT65-HF versions both on BW100. What did I discover? Well, first of all the HB9HQX is the fastest decoder by far, it decodes seconds earlier then the comfort and the slowest WSJT-X. But which one recieved best? Well, look at the picture and decide for yourself. I left all programs running simultaneously for a few time slots. Sometimes WSJT-X was better, sometimes the JT65 HB9HQX version or the Comfort version. A little comparisation from what you see in the picture:

Program   Call received    JT65-HF Comfort    JT65-HF HB9HQX    WSJT-X
Timeslot
20:22       EU6PW           -8dB                        -8dB                            -1dB
20:22       M0OAB          -14dB                      -15dB                          -16dB
20:23       IZ5WRC         -9dB                        -9dB                            -4dB
20:23       IZ2ZPH           -7dB                        -8dB                            -6dB
20:24       EU6PW           -4dB                        -4dB                            -1dB
20:24       M0OAB          -16dB                      -17dB                          -17dB

Actually this is only a 3 minute time span. I left it decoding a lot longer and you should say average WSJT-X decodes most of the time better as it produces better signals. Though I think it's just a difference how the signal is calculated in the software. Just like 2 different rigs with different S-meters. You don't see much differences between the 2 JT65-HF versions. What strikes me is the following picture, it is just a example from something that happened a few times.


WSJT_X missed the signal decode from SP6ECQ (at DF 175). Now I know WSJT-X 1.4 is beta. But may be it's not too bad to run 2 different programs at the same time when decoding. I tried to run WSJT-X 1.3 and 1.4 at the same time but that doesn't work. The last program started will decode, the other one stops.
And so, now you think WSJT-X is a bad receiver.....look at the next picture and get confused.


So what do you think? This time the comfort version decodes DC3XD with -25dB. The other progs don't even decode anything from DC3XD. I switched to WSJT-X 1.3 this time. What is happening here and what is the best decoder now? I don't know....decide for yourself! Or better test the programs yourself!

Friday, 3 October 2014

Testing the new WSJT-X v1.4 beta

As advertised the new WSJT-X 1.4 beta was brought out to download. This is a beta version and could have some bugs. I installed it on my desktop and had the idea it decodes very well. Be sure you read the installing instruction regarding the setup of your soundcard, I got the idea it is most important to create a clear signal. WSJT-X expects soundcards settings at 48000Hz 16bit. I made no QSOs yet with the program as it cannot connect to the comfortable JT-Alert yet. I'm so used to JT-Alert (call me lazy) that I'll have to wait till there is a compatible version made. So, you can hardly call this a test. There are some minor changes as far as I can see. Not shure why there is a astronomical display? It can be set off, but in the picture to show you. I think it can be used for EME or so? I would be happy to read how it is used? I think it is implemented because the plan is to merge WSJT-X and WSJT together. Another feature you cannot "click" on is a new one JT9W. Is it a new development, a wide version of JT9 that is even more sensitive? This is what I found so far about JT9W. I'm not a member and don't read the WSJT-X newsgroup on yahoo. I've been looking at it but it seems everyone has it's own problems, most of the time not really related to the software but because of not trying and reading.

However I made some JT9 QSOs on 40m yesterday with the old version of WSJT-X. 
With my QRP 5W on the alu tape vertical I was heard in Australia and made a QSO with VK4CMV who came back on my CQ. Try that with 5W SSB or even CW! One other QSO was with PE1BVQ after a sked. Hans is having a vacation about 80km south-west of me. Using 2,5W and his end-fed antenna he was pushing a mighty -11dB at my side at top. I made QRP QSOs in the past with Hans, but this was really strong. It was that strong that I decoded Hans on 2 frequencies in the waterfall. This happens to me sometimes, most of the time with QRO stations. It's like the signal has a mirror frequency, could be a soundcard problem? Anyone has the same occurence?

It is not really clear to me why people stick with the old JT65-HF program that was the standard before WSJT-X showed up. Joe W6CQZ abandond the project, he did a good job. Found little regarding to this as I don't follow any forums. M6GTG wrote about it in his blog.
WSJT-X is able to decode JT65 and JT9 simultaneously. JT9 being a very smallband mode has much more  potential as JT65 and still JT65 is more populair. Most amazing is that I recently made a QSO with a neighbourstation using JT65. It went very difficult as it seems my signal was out of his waterfall. Now he was using JT65-HF and talking to him afterwards he had never heard about WSJT-X. I guess we as bloggers should make some more publicity...

Wednesday, 1 October 2014

How to setup multiple accounts in eQSL

Why should you have more then one account in eQSL? Because as a portable station you are at different locations. Sometimes you activate a special place like a castle or a nature reserve in the COTA (WCA) and WFF programs. Probabely you like to send your contacts a special designed eQSL. Besides that eQSLs sent to your /P call are not placed in your normal eQSL box.

How to do it? Well I hope I can clearly explain. The first time I made a extra account I made a mistake I can still see at my account list. I can't undo it so I just entered a 1 minute time span at 1st of january 1900 in which I never made a QSO of course. I really don't know what happened exactly but you are not able to delete a account once it is made. I probabely made a error in the date or time and thought I should make another account because of that. If you make the same error, don't make the same mistake. If a date or time is wrong you can correct it at "My profile" inside the new account.



Above you see a list of the accounts made in my eQSL box. Every account has it's own eQSL design and it's own mailbox. If you have your account AG (Authenticity Guaranteed) qualified you can request that for other accounts as well.



When making a new account you just fill in the form that is below the "My Accounts" list. Make shure the call is the one you used like PE4BAS/M - /P or /QRP. Set the time of the activation right and take care about the for us europeans strange format of Month/Day/Year. Of course you need to have the right locator which you can easily find here. A nickname you can choose yourself as long as it is unique. Once you made the account it should show in the list. It could be you made a time or date fault after all. You don't need to make a new account but just log in the new account and alter the "My Profile" configuration. It's important you don't send your log directly from your computers logbook. Better make a ADIF from your activation log and upload it in your new account.



I hope this will help some other radioamateurs. And of course, don't make the same mistakes I made. If there are any questions I would like to read them at the comments. I'll do my best to solve any problems if I can.