Easter Sunday fieldday

20m groundplane with low feed point, 10 minutes of work to get ready
40m ground plane with elevated feed point, this takes roughly 30 minutes depending on the weather, still have to figure out a better way of mounting the radials.
Fully deployed 40m ground plane, with PA2QXT Michael at the controls of the FT-857D

Last update: 17-4-2017

Field day with FT-857D

Got a second hand FT-857 last week, you can’t tell from the printed label whether it is a FT-857 or the D or the ND version, and also there are options like a TCXO and various filters. This one seems to be the D version because it has 60m and it has DSP filtering, and the CW filter is clearly there although I probably won’t use it. The receiver performs like a charm, maybe it seems somewhat noisier than the FT-991 but, if you play around with the RF gain and the filters, and if you listen on the headset then it is a very acceptable transceiver. No ATU, so your antenna SWR needs to be under 3 (probably), but to be honest, it is not very difficult to tune the antenna with a separate analyzer. Already did this for the vertical whip for 20m so I took the FT-857 in the field and made some QSOs.

FT-857 on the dashboard, it ran for 1,5 hour on a 3S lipo and I made a couple of QSOs. When the 3S lipo goes below 11.4 Volt I normally stop.
The whip got some tie wraps to prevent collapse, as you can see the weather was somewhat chilly, as was the 20m propagation on the 14th of April.
I modified the magnetic suction clamp from MFJ and added three radials, and a choke balun. For 20 m my car roof is not large enough to form a decent counterpoise, with the radials it works fine. The farmer did not care whether I was there with the car, we had a chat about his smart dog and antennas.

I like this set-up for in the car, it is easy to do, easier compared to getting the FT-991 in the field. The 857 fits on your dashboard, everything (cables headset, mike, ropes) fits in one suitcase, with the 991 I end up carrying at least a bag next to the suitcase. Getting my tuner to work with this set still needs some work, the LDG YT-1200 is designed for the CAT interface, and not a CAT-IV interface, so I need a conversion cable and some conversion electronics.

Last update: 15-4-2017

Westerbork, Dwingeloo and field day

Some photos made last week.

Close to one of the antenna’s in the Westerbork radio telescope array
Before Westerbork we had Dwingeloo, currently this dish is used by PI9CAM, see also http://www.camras.nl
Fieldday 8-apr-2017
40m elevated ground plane
This is the antenna I tested on the 8th of April and I call it an elevated ground plane for 40m. The essential part is the 9 meter of wire that you loosely wind around the mast. Use an antenna analyzer to tune it. The simplicity is that it works on a glass fiber mast without any guy wires, the tripod at the base is sufficient to keep it upright, secure the tripod with three tent pins. At 9 meter with 5 turns the antenna is resonant in the high part of the 40 meter band. The length of the radials is not critical, the box is a straight through, it has a SO-239 connector, center pin goes to the vertical and there are several bolts with butterfly nuts on which you attach as many radials as you carry, I always carry four of them. At the end of the radials I fix them with a tent pin. The transceiver is kept 20m away with a RG-58u 50 Ohm coax cable which is light and flexible which is ideal for field activities, the transmission line loss at 7100 kHz is negligible, we only run at most 80W on the transceiver and we avoid any tuner. The transceiver was a FT-991 running on a 3S lipo battery 5000 mAh. I got the mast at dx-wire and the batteries at CONRAD.

Last update: 9-April-2017

Field day 2-April-2017

Two blue sky Sundays on a row, so I had to go outdoor with the radio.

1:1 balun (diamond BU-50) mounted directly under the top mounting point of the guy wires, this prevents sagging of the glasfiber mast. Mounting it above this point is no success.
Purpose of the day was to tune the 40m dipole, in this setup it is an inverted V with the highest point approximately 8 meter above the ground. Within 3 iterations I had found an SWR below 1.3 for the entire 40 meter band. You don’t need any tuner.
The mast looks better I think than last weekend.
The 40 meter conditions were not splendid, and there was a SP DX contest, I just made 3 QSOs.

Last update: 2-April-2017

Field day 26-Mar-2017

The challenge is, arrange yourself in such a way that you can hike for several km, carry a GFK mast, a 100 Watt transceiver, batteries, cables, tuner, and all antenna material without the help of anyone. Today I came close to this, I had a suitcase and a separate bag, and a mast attached to a tripod. It is not comfortable hiking, but it worked.

20 meter antenna, 3 radials of 10 meter, and a MFJ 1979 vertical
GFK mast with an end-fed 40-20-10 meter
A bag, a suitcase and a mast+tripod
Blue skies, guy wires and antenna

Last update: 27-Mar-2017