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Reverse Beacon Network spots using my EFHW and QRP 6 watts

Why I love end fed half wave (EFHW) antennas

November 16, 2021/0 Comments/in Amateur radio /by Stefan Helander

The antenna seems always to be a compromise between practical matters and performance. While not being the most high performance antenna, I find the end fed half wave (EFHW) a very practical antenna, especially during portable operations.

The EFHW doesn’t need to be straight. It can be bent in angles and be “abused” a lot.

In this video I have a temporary installation in a vacation home (time share) where I am not able to erect any masts, not being able to use trees or other houses as fixation points for my antenna. I used some zip ties only that can be removed without leaving any marks.

The antenna height is far from optimal and the antenna is bent several times. It is also close to the rain gutters made of metal. Still I have fine SWR levels on all bands (10/15/20/40 m) and can work all of Europe on my QRP rig (6 watts) (see the screenshot from Reverse Beacon Network).

pfSense port forward to a NAT:ed IP-address located on the other side of a ipsec tunnel

November 13, 2021/0 Comments/in Network /by Stefan Helander

This is kind of a special scenario but actually occured for me. A port on the pfSense WAN should be NAT:ed to an IP-address located on a remote subnet via an ipsec tunnel. The problem here was the router on the other end of the tunnel did not route all it’s outgoing traffic over the tunnel. Only a few subnets behind the pfSense went through the tunnel. All other traffic was using the routers normal Internet connection.

In the image above, a port (123 in the example code below) on the pfSense (100.1.1.1) should be NAT:ed and port forwarded to 10.0.0.7. The result was the NAT:ed port forwarded packets reached the intended host (10.0.0.7) but replies probably went straight back on the internet, not going back through the tunnel.

I solved this by setting up a simple proxy on a server using iptables located on a machine in one of the subnets at the pfSense site which was reachable from 10.0.0.7 through the tunnel. See next image.

The proxy was made using iptables in a Ubuntu machine on 10.2.2.2. Both the proxy server on 10.2.2.2 and the host 10.0.0.7 could reach each other over the ipsec tunnel.

In pfSense I changed the NAT / port forward of port 123 from 10.0.0.7 to 10.2.2.2 (and deleted the existing states in pfsense from my previous tries, until I did that, this didn’t work).

The proxy server using IP-tables was set up like this (guide found here):

sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A PREROUTING -i ens160 -p udp --dport 123 -j DNAT --to 10.0.0.7
sudo iptables -t nat -A POSTROUTING -o ens160 -p udp --dport 123 -j SNAT --to-source 10.2.2.2
sudo iptables -t nat -A POSTROUTING -p udp --sport 123 -j SNAT --to-source 10.2.2.2

You will probably want to make sysctl ip_forward and iptables statements persistent over reboots.

Ispconfig3 monitor tab not opening when using non-english language [BUG – WORKAROUND]

October 30, 2021/0 Comments/in Ispconfig /by Stefan Helander

This is caused by a bug when saving the translation file concerning the langauge key for “Let’s Encrypt log”.

When the translation file for the Monitor tab is saved, the necessary backslash before the ‘ in “Let’s” is not saved into the file. The problem is described in this bug report: https://git.ispconfig.org/ispconfig/ispconfig3/-/issues/5881 but for the moment not resolved.

To workaround this problem, manually edit the file /usr/local/ispconfig/interface/web/monitor/lib/lang/XX.lng (where XX is your language). Find the line beginning with:

$wb['Let's Encrypt log'] =

Insert a backslash like this:

$wb['Let\'s Encrypt log'] =

Save the file and your Monitor tab will work again. This must be repeated each time you edit the translations for monitor.

How to open and clean a water lock in a floor drain looking like this (see photo)

October 14, 2021/0 Comments/in Doityourself /by Stefan Helander

In a house in Denmark I needed to clean the water trap in a floor drain looking like the one in the photo. (For some weird reason, these kind of household tasks always end up on the male… But that is another discussion :).)

I wrongly made the assumption that I needed to unscrew the four screws. Bad decision! This made the upper and lower part of the water lock to separate and the lower part fell into to the waste water pipe. Fortunately there was a bend some 30 centimeters down so it stuck there and I only (!) hade to put my arm into the pipe, grab it and pull it out.

To get the water trap out was actually more simple than anticipated. This how it should have been done: just put your gloves on, stick two fingers in the big hole and a thumb at the edge and pull. When removed and safely away from the waste water pipe, the four screws can be unscrewed in order to separate the two parts of the water lock so it can be cleaned more easily.

Anytone AT-D578UV Toyota Prius installation

Anytone AT-D578UV stealth installation in Toyota Prius (2008)

October 9, 2021/0 Comments/in Amateur radio /by Stefan Helander

I wanted to make a “stealth installation” of my Anytone AT-D578UV radio in my Toyota Prius (2008) so I don’t have to worry so much for burglars when parking the car. Below the FM-radio is a compartment, when removed, leaves a space big enough for the radio.

There is plenty of space behind the compartment. I was a bit worried about that issue becase the radio is longer than the depth of the compartment, but it turned out there is enough empty space behind it.

I installed the radio with the programming cable connected as it will be very hard to connect it after the radio is mounted in the car. The microphone is extended and connected using a flat straight ethernet cable and both cables are dropped downwards and pulled out from behind the panel. That way I can easily hide the microphone when parking the car.

When the compartment under the radio is removed (and saved to be reinstalled when selling the car), the space between the metal plates is to wide, so I took a 5 mm nylon cutting bord that I cut into pieces and glued them together to form a suitable spacer and drilled a hole for the mounting screw. I did not use the mounting screws that came with the radio, instead I used one M4x20 mm and one M4x40 mm. On the right side of the radio I used 2 nylon pieces and on the left side 5 or 6. The screws went into the rear holes on the radio and to get some support for the front I used zip tie straps around the radio through the holes in the metal plates.

The GPS was just tucked up behind the navitor screen, just to the right of the speaker.

For power, I routed two 6 mm2 wires directly from the battery (with a 30A fuse close to the battery) and routed them through the left trunk panel and inside the side panels below the doors to the front. The antenna cable went the same way and I didn’t want to drill a hole in the car so I used a trunk lid mount even though the performance for those are often not as good.

Useful videos

These are some useful tutorial videos as you need to uninstall and reinstall the stereo in order to install the Anytone AT-D578UV below it.

Car stereo removal

How to remove trunk interior, left side, for cable rerouting. Use parts of this video. You don’t have remove all interior as the video shows.

Car stereo removal, parts of this video is very useful

How to enable Talker Alias on Anytone AT-D878UV / AT-D578UV

October 8, 2021/0 Comments/in Amateur radio /by Stefan Helander

With the number of assigned DMR ID:s on radioid.net going over 200.000 we are over the limit of the capacity for the Contact List on the older Anytone models. Anytone:s under estimation in design is not the first in history. Remember Bill Gates saying that no-one, ever, is going to need more than 640 kB RAM?

So we need to select which regions of DMR ID:s to incluide in our contact lists in our Anytone radios.

In addition to that it is a good idea to enable Talker Alias to sort of increase the chance of just not seeing a DMR ID in the display. Not all repeaters supports it though.

Make sure your own Radio ID Name is set in the form “CALLSIGN Name” (your callsign and first name separated with a space). Set your radio on a DMR channel, then MENU -> Settings -> Chan Set -> Radio ID -> select your ID -> Option -> Edit Name -> Confirm
MENU -> Talk Group -> Talker Alias -> Alias Tx Set -> On
MENU -> Talk Group -> Talker Alias -> Alias Rx Dis -> Contact First

Joomla! T3 Framework based template, module class suffix not working

September 14, 2021/0 Comments/in Joomla /by Stefan Helander

The problem was that module class suffix was not working and the first solution was to make a tpl file override, placed in local/tpls/blocks and change style=”raw” to style=”xhtml” for the module in question. This solution had been working for years, but suddenly the client reported that their site was “looking weird” again.

It turned out the module class suffix had stopped working again.

The solution this time was quite simple. The site had been updated and the T3 system plugin was version 3.0.2. By updating it to 3.0.4 the problem was solved.

Microsoft Internet Explorer opens Edge

September 6, 2021/0 Comments/in Microsoft /by Stefan Helander

Microsoft is phasing out Internet Explorer and moves over to Edge. In order to facilitate that, some users experience that when they click on the Internet Explorer, it actually opens up Edge. In rare situations, the user might need Internet Explorer instead of Edge.

It is possible to override this.

Start Microsoft Edge and open edge://settings/defaultBrowser
Find the settings for “Let Internet Explorer open sites in Microsoft Edge” and set it to Never
Click on the Internet Explorer icon. Now MSIE should open.

“There has been a critical error on your website. Learn more about debugging in WordPress.” and web error log reports “Call to undefined function the_field()” [Solved]

August 20, 2021/0 Comments/in WordPress /by Stefan Helander

After an upgrade of WordPress, the site reported “There has been a critical error on your website. Learn more about debugging in WordPress.”. When investigating the web server log files, errors reporting “Call to undefined function the_field()”.

Solution: During the upgrade process, the plugin “Advanced Custom Fields” had been disabled. By activating the plugin, the problem was solved.

Cisco RV160 RFI-problems [fixed]

August 19, 2021/0 Comments/in Amateur radio, Hardware /by Stefan Helander

Being an amateur radio operator (or HAM-radio operator) I need to use electronic devices with as low radio emissions as possible in order to keep a low noise level on the shortwave bands (or HF-bands). I found out that my Cisco RV160 router was one of the major sources of radio noise (RFI or Radio Frequency Interference) in my home. It turned out it was easily fixed as the culprit was not the router in itself, but it’s power supply.

The router runs on 12 volts DC (original power supply rated up to 1,5A) which is often available in the ham schack already. So in that case, get rid of the original power supply and hook up the router to your 12 volts DC supply in the shack. In my case, the router was located in another part of the house so I just replaced the power supply with another, transformer based power supply. In my case, a Mascot 6823, rated for 12 volts DC, 1A (intermittently up to 1,3A). Even though not the same amp rating as the original, it seems to be sufficient.