QRPguys digital FSM continued

After waiting for a answer from QRPguys for over 2 weeks I noticed KY6R Rich wrote about a QRPguys "paraset" kit designed by Steve KD1JV. I thought Steve might be able to help me out with the modification on the digital voltmeter module. So I decided to send him a e-mail and within a few hours I had a helping answer. Actually basically it would be a trail and error try to modify the voltmeter, he explained how to measure from the yellow sense wire on which resistor to short out. He also told me instead of a 100V type I should take a 30V type without mod. But this solution would take weeks before I have a new module.



So I took another look at the diagram supplied with the kit. It shows a jumper from the yellow sense wire shorting out a resistor and a potmeter which are connected in series. Thinking that this is always the same whatever the lay out I started to measure several junction to find out were to solder the wire. The picture at the right shows the results. The conclusion is that when I solder a wire between point 3 and point 1 I short out the potmeter and the resistor below the potmeter which are obviously connected in series.

Not shure about everything but I decided to continue with the last part of the kit. Mounting the voltmeter and the sense potmeter on the printboard. Soon it was evident the bushings supplied could not fit, they are too wide (or the screws are too short ;-) ).  I decided filing them, but the material is very tuff. It took a electric powerfile to get anything off.



The result including the short out wire can be seen on the picture. Ready to assemble without any difficulties this time...



Below the finished project finally working:

Testing: I hoped for a more accurate FSM but so far it is just a indicator just like a analog FSM. The potmeter is not sensitive enough to set it to a accurate value. So, if you finally set it, for instance to 10 as a start value, next time you switch the meter on it is on 15. When you only touch the potmeter the value will change. I might look around for a 10 turn potmeter to increase the sensitivity in the future.

The push button, by the way, is a momentary on switch in parallel with the normal on switch. I had to read the manual several times before I discovered why it was there. Just for information ;-)

Testing the vertical on 17m/160m

I always like to test the propagation on the edge. Looking for contacts on the highest band possible. Yesterday evening that was 15m (21MHz). But although I did see some stations they didn't see me. So, down one band to 17m (18MHz). I was immidiatly successful in making QSOs to the West Indies and Central America, later also North and South America. ODX was with CX7BBR from Uruquay (11529km).

When propagation faded later on I thought I try the lowest band possible, I didn't try 160m yet on my new setup. On 1840KHz I saw a german station calling Japan. So a quick view on the Japanese FT8 frequency 1908KHz revealed I did receive at least one Japanese station. For the fun of it I just tried with 50W not expecting anything. A few moments later I had 4 (!!) Japanese stations in the log.

I can't imagine it is just the vertical I use. There has to be excellent propagation yesterday evening...
But so far I am impressed with the results.

Pre-winter antennawork finished

The weather forecasted was good, but the real weather was bad today. We had rain almost the whole day again. Between the rain at some dry moments I finished the antenna task. It was only a matter of mounting a radial and connecting the antennatuner to 12VDC. What I basically did is to connect the radial via the front of the LFA and back to the tube that holds the antennas. The end was fold back a little so it would fit. You can click at the photo on the left to have a good view.
The 4 element LFA is much larger as my HB9CV, will it be so much better? I have to test it out.

The vertical does work the same as before. I always appreciated this antenna. But is it that good compared to the inverted-V? Well, I've done some tests with mixed feelings. The "one" radial construction gives it some directivity, how much?..Well 1dB or so, no shocking difference. The antenna is 7,5m long and the radial is 7,5m long as well so it is a "balanced" antenna. However the CG3000 is not a balanced tuner. It tunes well on all bands exept for 12m. I might construct a 1:4 balun to insert between the tuner and the antenna to get a easier impedance matching. Have to think about that. Hope someone can give me advice about this??
I tried it on 15m this afternoon and got surprisingly good reports from W4GHW (+4dB) and OX3HI (+12dB), which of course tells me nothing about the antenna but more about the propagation. I mentioned before, propagation is not always reciproke. Today was good for me to TX I guess and less good for RX.

Europe...

The results from the vertical are not disappointing on 40-15m till now. On 40m/30m it is certainly better as my inverted-V, on 20m, 17m and 15m I had high hopes but it is just slightly better, sometimes the inverted-V is better. I tested at daylight and most stations are from europe. I received some from the USA on 20m and they were strong (S9) but they had almost the same signal on the inverted-V. On 60m and 80m the inverted-V wins by many dBs. I didn't hear any signal on 160m so I have to test that later.

The LFA...well it has a excellent SWR over about 2MHz bandwidth, really incredible. But not much propagation on 10m today. However, monitoring for a few ours always gives some results...

And while writing this VP8LP from Falkland Islands was spotted several times.

CQ CQ...

The fun is that I had a german tourist sightseeing my antennas just after I had everything in the air again. DL1BFE Gregor from Borkum actually, we met on lightship the Borkumriff in 2013. Unfortuntately he and his wife had to get on the train to the Eemshaven to get home again with the Ferry. I just discovered Gregor is a autor of some interesting books: http://www.gregor-ulsamer.de/