Tag Archives: WSPR

40-20-15m EFHW Round 2 – Update

WSPR results o 40m and 20m WSPR look good with the EFHW. here is 40m during nightime hours:

2017-12-11_9-54-35

And 20m for just a few hours yesterday and so far this morning:

2017-12-11_9-55-11

On 40m there have been 103 unique heard vs 106 heard by (@1/2 W). On 20m, this is 124 unique heard vs. 74 heard by (also @1/2 W). These numbers indicate good overall performance.

I found a great write up on how to build one of these antennas titled “A Shortened Multi-band End-Fed half Wave (EFHW) Antenna for 80-10m” by Steve Nichols, G0KYA.

I am going to do some work on how to best deploy this in the field given my typical situation (i.e. lack of tall trees). this could be a great Field Day antenna.

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40-20-15 EFHW

Here are the 24 hour WSPR results on 40-20-15m receive using band hopping. They appear to be pretty consistent with current band conditions and while not as good as the 1/4 wave vertical it is a very respectable and very portable multi-band antenna.

40m40m

20m20m

15m15m

The SWR plot is as follows:

swr

These antennas are increasingly popular and many quality antennas sell for ~$140. Building your own is very simple and I would estimate my cost to build this would not be greater than $30. This will work out to be a good antenna for portable or field day use. It is not especially sensitive to mounting or orientation.

 

More Test Results of The Ground Beam QEC Antenna

Tried 20m FT-8 early this morning as VOACAP indicated this was the best time for EU contacts on this band. My signals were heard toward the Northeast US but very few were heard in the EU. I made no QSO’s. WSPR results over 24 hours are here:

wspr mapo

This data appears to confirm that this antenna is directional (I have it pointed at a 45° bearing from my QTH)  but the F/B ratio is still relatively poor. The antenna is about the same as the 1/4 wave vertical overall. I must say that my single reports in the forward direction on SSB have been very good. Propagation on 20m is not helping. VOACAP shows the following based on 100W SSB with the receiving antenna based on a dipole at 10m:

prop1prop2

20m has been largely dead after dark. This chart indicates that 20m contacts with this combination of antennas and power will be challenging to the EU.

Overall, The ground beam – QEC antenna is an easy to carry and deploy vertical antenna with just enough directionality to help in some situation. It is well suited to my QTH on filed day as it has a wide enough bandwidth to cover the USA and Canada.

Initial impressions of the Timewave ANC-4 Antenna Noise Canceller

My used Timewave ANC-4 arrived yesterday from Ebay. It lacked a power connector which fortunately I had in my junk box. I wired the cable up and added some power poles. It came with an antenna that consists of about 8 feet of wire connected to the center pin of an RCA plug. I set this up roughly vertically inside the shack. The unit must be grounded to work effectively with this wire antenna. I fiddled with it awhile but did not have much luck in reducing noise initially. Per the manual, the first thing to try was ensure that the sense antenna was picking up the noise at about the same amplitude as the main antenna. The receiver is setup to an unused frequency and the noise level measured on the S-meter. The phase and noise gain controls are fully CCW. The  main antenna was disconnected and the noise gain adjusted until it matches the S-meter reading  measured previously. The main antenna is then reconnected and the phase control is adjusted until a null is found.

This took awhile to figure out but with the IC-7300 it is easy to see the results on the waterfall. As you get close to a null the background on the waterfall will darken and signals will become more distinct. I estimate that the change is about a 2 S unit reduction in noise. I have run the unit on 20m WSPR and over a 1 hour period had 42 unique spots compared to N5CEY’s 21 unique spots.

So initial results look promising. I will need to work more with this and collect some data on to its effectiveness.

Insight from running 20m WSPR

The 40m vertical has been deployed for the past few months supported by a 10m SOTAbeams travel mast. It has held up well to the abuse of constant use over the summer. We had a few windy days last week and some of the seconds of telescoping pole retracted so I had to bring the whole thing down to fix. During this time I ran the 20m vertical on its own using 20m WSPR for receive only. Over this two day period I was comparing with Cliff’s (N5CEY) 20m WSPR station about 15-20 miles away near Bayview. Cliff consistently gets a larger number of unique spots as well as a larger amount of DX calls with his setup. Cliff is in a rural setting while I am in the middle of the city. What the WSPR data is telling me is that my noise floor is higher so I am not receiving as well as Cliff does out in the country. I took some measurements with the IC-7300 at various times of day and found the following noise floors:

Band Time
1800 UTC 2100 UTC 1300 UTC
80m S3 S4-S5 S6
40m S6 S6-S7 S9+5
20m S1 S2 S4-S5
17m S3 S3-S4 S5
15m S3 S1 S7
12m S2 S0 S3
10m S1-S3 S1 S5

These measurements were made with no preamp on 20m and below. All others had preamp #1 engaged. Friday night was awful, S9+ noise on 40m! Dick, WB5B said it best: “WSPR is telling you that you have a noise problem!” Doh!

630m WSPR

Cliff, N5CEY, has been listening to 630m WSPR stations over the past few days and has been consistently picking up three or four stations a night with his antenna system. I thought I would try the same using just the mini-whip antenna and the SDRplay receiver. The mini-whip has been fairly decent on the lower bands. I cranked up HDSDR and when I tuned to the WSPR frequency of 474.2 kHz and found a huge amount of inter-modulation products from local broadcast stations. I tried lowering the gain but they didn’t go away. Looks like I will need a low pass filter or an attenuator.

I then switched to using the SDRuno software that goes along with the SDRplay. It has some filtering features that I thought would be useful to try. The waterfall looked a lot quieter with this software for some reason and after piping the output to WSJT-X I was able to decode 630m WSPR spots from three stations overnight. This compares favorable to what N5CEY saw over the same period.

I will be playing with this some more to see if I can further optimize the receive.

IC-7300 setting to work with WSJT-X (and others)

I prepared a short how-to on setting up and ICOM-7300 with WSJT-X for working digital modes. If you can get this working, other digital software can be easily configured in a similar fashion. The file can be found on the “Projects” page or from this link:

ICOM 7300 Setup with WSJT-X

WSPR Data collected from the 20m Hamstick Vertical Dipole

Here is 24 hours of WSPR data collected from the 20m Vertical Dipole:

20170814_013033000_iOS

There were 114 unique receive spots and 90 unique heard from spots with 1W transmit. This seems low compared to N5Cey’s 20m 1/4 wave vertical which typically receives 180 to 200 unique spots from his QTH near Los Fresnos.

I did some A vs. B tests on SSB yesterday switching between the 1/4 wave vertical and the vertical dipole. This time I used a remote receiver using Websdr.org. I connected to a station in the San Fransisco area and monitored my voice transmissions. In this case the vertical dipole came in about 1 S units stronger. I then switched to a station in New Jersey and the opposite was true!

I am going to do some additional testing on various 20m vertical configurations using WSPR over the next couple of days.

Completed Linked EFHW

I completed the linked EFHW later yesterday afternoon and tuned the 15m, 17m & 20m bands. I removed about 6″ of wire to tune 15m, 2″ to tune 17m and about 3″ to tune 20m. The antenna is deployed vertically on a SOTAbeams Travel pole up 30 feet. I am using a TV mast tripod as a base. In the field I would lash the mast to a fence post or other similar support.

I tested the antenna on my base rig at 100W and made three easy SSB contacts. Two of these were EU DX contacts. I  left it tuned for 20m and ran WSPR for the last 12 hours. Here is the map:

2017-06-22_7-27-12

This works out to 112 unique heard spots with 66 unique heard by spots when running 1/2W. Looks like the antenna is a winner for Field Day! Only thing I will likely try today is adding a 1:1 choke as I am seeing the SWR swing a bit on SSB transmit.

Some Thoughts On WSPR Data for Antenna Comparisons

I have been keen on using WSPR data to compare the performance of antenna systems. I haven’t worked out a detailed metric but I thought I’d share some thoughts on how the data can be broken down. When looking at 24 hours of WSPR data on a specific band I am seeing the the number of unique stations received is a clear indicator of the antenna’s overall performance and pattern. If this is enough to make the WSPR Challenge board for that period then another clear indicator. As an example, the homebrew Buddipole on 20m (even with resonance being outside the band high) came in at #22 on the WSPR Challenge site with 143 unique stations. I have been hard pressed to make the WSPR Challenge board with the end fed horizontal or the magnetic loop antenna (indoors). So the higher then number the better.

The number of stations hearing me on WSPR is a different story. The ratio of stations heard to stations hearing me is rarely equal. This really depends on the efficiency of the antenna, something that is not evaluated on receive. If I transmit at 1/2W I can expect fewer stations received than if I transmit at say 1W. This will not be a linear increase. What I am seeing is that some antennas have a high count of “heard by” stations for a given power than others. This gives a relative indication of the antenna efficiency. There may be a way to correlate this with a given antenna by testing at different power levels.