My equipment

In recent times I have renewed my interest in portable operation specifically using QRP radios. My equipment is an FT817 and a Ten-Tec Argonaut VI. My antenna is a home made linked dipole for 20 and 40 metres together with a light weight SOTA linked dipole from England.

My linked dipole is rugged and great for parks use and probably alright for a summit as well. I use Mark’s (Tet-Emtron) dipole centres and the Kevlar centred wire. This wire is very strong and light and does not kink. Its construction is similar to coax. There is an outer plastic insulating cover, a mesh conductor (braid) like the shield in coax and the centre contains the Kevlar. My approach to soldering this wire is based on a few experiments. Where the wire goes inside the Power Pole lugs I stripped the outer insulating material off to the correct length, then pushed the braid back and very carefully, using side cutters, trimmed three millimetres of Kevlar off allowing me to then twist the braid into a point or spade shape. I lightly tinned this and then placed the Power Pole lug over the wire and applied a hot iron to that point on the lug where the cylinder containing the wire gives way to the spade. The solder flows through the cracks. I then run the iron down the join on the cylinder to complete the assembly. You will notice that the soldered joints are not load bearing. To erect the antenna slide the dipole centre hole over the squid pole ensuring that the SO239 is facing down. Attach the coax before pushing up the squid pole.

I have two ways of mounting a squid pole. The first is to use a PVC plastic sleeve slightly larger than the base of the squid pole and lash the sleeve to a post, rock, fixed picnic table or something similar. The sleeve protects the base the squid pole from being crushed. The second method is to mount the squid pole on a tripod (in my case a speaker tripod from Jaycar). You can see this approach in some of the pictures. I have made a bracket that fits over the top of the tripod and this contains two baluns for antenna experiments. On occasions with light winds I do not need to guy the tripod or squid pole, but if the winds are reasonably strong I guy the whole assembly. You can see this in the picture of the Cooltong CP activation.

Tet-Emtron dipole centre

Tet-Emtron dipole centre

Front side of dipole centre

Link assembly (20 & 40m)

Link assembly (20 & 40m)

Well you might ask, what’s the difference between an FT817 and a Ten-Tec Argonaut VI as far as portable QRP operation is concerned? The major differences between the two transceivers are as follows: the receiver in the Argonaut is better and less prone to suffer from strong signals near by (5 KHz or less)  and second, the Argonaut has a splendid variable width SSB filter, which is really effective. There are many other differences, but the ones that count are the Argonaut has a speech processor, the current drain is less for receive, the display is larger and visible in bright light (using the default colour of blue) and the DSP is excellent. However, it is a little larger than the FT817 and, while it is rugged, it is not as suitable as the Yaesu as a back pack radio. I have fitted the 2.4 KHz SSB filter to my FT817 and it does improve receiver performance. I like both radios and will admit my comments are entirely subjective!

Front view of Argonaut & FT817

Front view of Argonaut & FT817

Side view

Side view


3 thoughts on “My equipment

  1. Pingback: My portable antenna/s | vk5pas

    • Hello Sergio,
      thanks for the comment. I still use that antenna quite a bit and it has survived the many variations of putting it and and down without a problem. Mine, as described in my blog, is for 20 and 40, but I have built a second for 30, 15 and 10 metres. I have a SOTA beams linked dipole for SOTA activations where I use my FT817. It is much lighter than my home brew antennas and fits in my back pack. Good luck with your antenna in the field. It is great to hear from you
      73 John D VK5BJE/VK5PF

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s