A Bit of Spring Tidying Activity. Much More Needed. [not really ham radio]

While it is not quite spring, today's weather had a touch of spring here. Sun shining from a clear sky (not often in Denmark), and the temperature quite acceptable. Well, I say not quite spring because it is still February, and that is still officially considered a winter month.

After a long time with COVID, the tidying activity had been lacking here, so now a lot is needed, and finally, I got started.

Indoors the living room space got a little floor space freed. Much more is needed, but it is now possible to have a guest sitting in the few (more) square meters (sqm) available. Yes, it was that bad, but it is a start, and must continue. ;)

In the out-house (I would not call it "shed" because it is much bigger than a shed in my eyes. A total of about 40sqm (about 400sqft) sounds like a lot of space, and while some stuff has been removed from the out-house after my removal some years ago, A lot still needs to be done there, so I can start some workshop activities, including some antenna preparation work.

I need to look at all the stuff on shelves, to see what is useful to me, and what should be discarded, and what must be discarded. A lot of sorting to do, but finally it has started.

In the indoor department, there are some thing needed. The bathroom is over 50 years old, and it needs a complete renewal. Since I am lousy at that type of work, I have decided to have it done and saved enough to pay the bill. It had been postponed due to COVID, but now I need to have it done.

Raspberry Pi as Shack Computer.

 The fan in the 8GB Raspi is failing. The SD card for the 8GB Raspi has veen re-located to a 4GB one in a casing with passive cooling. Some web browser tabs have been closed, so for now the 4GB is running as shack computer with reduced memory.

Casing(s) with passive cooling has(have) been ordered for the 8GB. The "old" SD card from the passively cooled 4GB Raspi has been re-located into the Raspi400. That SD card was set up as SDR, so I can monitor the QO100 satellite again.

I may be able to find a usable fan to replace the defective one, at least until the new casings arrive. 

When that happens I will have the following Raspberry Pi 4/400s available:

1x Raspi 4 8GB, should be the shack computer for browsing and logging, maybe back-end for VNC

2x Raspi 4 4GB for SDR and/or digimodes

1x Raspi 400 (4GB) Probably digimodes, some (circuit) and/or antenna design software.

Apart from that, I have a couple of Raspi 2s, usable for digimodes and/or QRSS monitoring, likely running a VNC (or other remote) server, so they can be remotely operated.

A Few QRP QSOs with CW on the QO100 Satellite.

 Yesterday I got my SDR connected to the converter again (after a long pause), after re-arranging the shack corner.

When I saw some signals in the CW portion of the transponder I found PY2PIM and tried to call him, he was gone.

In stead of just giving up, I moved up a few kHz and made a CQ call, and voilá! There he was. 

After the QSO I was called by several stations, activating the LEILA (overload) system, so I could not hear them immediately. I made 6 QSOs all in all. 2x PY, 2x SP, 1x E70, 1x G)

Not bad for a single CQ call.

Since my output to the antenna is less than 3W, I will consider those QSOs as a part of my personal QRP challenge. We shall see how many satellite QSOs I can make this year with this set-up.

On HF the QRP QSO count is up to 80 this year, so I should be quite capable of reaching my challenge goal of min 365 this year.

Small Update on the Solar and Batteries.

2 small updates in one:

1)

The 20Ah Battery (lead-acid, so more or less effectively 10-12Ah) has been prepared and connected to the solar charger with the 50W panel. The battery was full, so charging is intermittent.

With this I should be able to run the IC-703 on receive 24/7, as it draws less than 300mA. (x24 -> 7.2Ah/day) There should be sufficient juice from the panel to charge 10Ah on a daily basis, with a bit to spare on very cloudy days. I will have to set up a test.

If that works nicely, a DC/DC boost/buck converter "lab power supply" will be added, so I can do more electronic experiments at the operating place. I have a 24V DC operated soldering iron, so that should be possible to operate as well, with a DC /DC boost converter. For that I might need to set up a larger 24V system with he two 100W solar panels, the second charge controller and 2 larger batteries in series.

2)

On the advice of a friend who has I have increased the possible current draw for the "revived" 28Ah batteries, and increased the voltage to the max "allowed" 14.4V. This is to see if the current stabilizes at a lower level, indicating that the battery is fully charged. 

If that looks good, some charge/discharge tests need to be done to determine the energy storage capacity of the batteries. If that works with the two batteries that look like being close, they will be added in a second solar system, likely running as a 24V system.

3)

If all this works, I may use some 20-25W panels I have available with a charge controller to start reviving other batteries, so I can use (at least partly) solar power for the revival of old batteries, in place of using mains power all the time.

4) 

Yes, I can see already that I will have to do more with panels/controllers, and then start using LiFePo4 batteries for higher power. That will be a whole new adventure, so it will be a bit later.

Some Solar Power Activity to Come.

 The past years my activity on the solar front has been lacking, but now I should get it improved. Here are some thoughts.

I started preparing (somewhat larger lead-acid) batteries for use in the solar power system, as replacement for the (too) small battery I have connected at the moment - that one got depleted last winter during the *very short* charging phases in midwinter. The solar panel has been moved to a better position, but I still need more buffering. For now one of the batteries will be setup for solar, the others will be set up as buffers if main power is lost. I still have one more solar charger, so I could probably get another battery running on solar (when the weather improves). I might also find a few low power 12V solar charger/controllers for use with the smaller batteries. As long as we are talking lead-acid batteries a "float charger" could probably be of service

That means that two batteries, 18Ah and 20Ah, are being charged, so they will be ready to receive charge from the solar charger, and will not be depleted by supplying power to the charger when no sunlight is available. Later I may go to pick up some 12V/45Ah batteries designed for electric scooters. They are available locally. 

I do have a few more panels to set up when the weather improves (right now the weather changes between frost and sunshine, then storm and rain. Not good for outdoor work, such as setting up solar panels and/or making/maintaining antennas.

Right now the setup uses one 50W (12V system) solar panel.with a battery of around 7Ah - too little buffering. 

The first battery being made ready to run with this panel (initially) is a 20Ah one. That should provide about 10Ah usable per day, i.e. 120Wh. 

I have two 100W (12V) panels that can be mounted, and some 20(25?)W panels somewhere, they need to be located and put to use, too.

My two charge controllers can be used in a 24V system, so there is an option to use this with a DC/DC converter to a 13.5V system, with a decent efficiency. 

I will need some calculations to see what I can drive with that setup.

In the long term there is no doubt that I should use LiFePo4 batteries, as they are lighter and have better storage efficiency/capacity. In addition they are, in the long term, less expensive than lead-acid batteries.

Further, two of the 4 (almost dead) recycled Pb batteries (nominal 28Ah) look like they should go into a cycle of charge/discharge, to get them up to a decent capacity (probably 20-25Ah).

Update On the QRP Challenge.

 Almost every day I have been working QSOs with the 5W output CW, mostly from the IC-705. QSOs have been made on 10-12-15-17-20-40-80m.

Now we wait for 4 and 6m to open - and 2m in the summer Es season. I suspect that I will mostly run more power on those bands, but some 5W work will be tested in the big openings.

New antennas are needed, so I can include 30-60-160m. Initially I expect to make and use a 30m vertical 1/4 wave GP, usable on 30-10-6-4m, probably good enough to listen on 8m (40MHz).

Next antenna will probably be an EFHW wire antenna for 80m. That should work on all HF bands except 60m, and with an extension coil it should be extended to work on 160m. I do have the transformer (49:1), it must be built into a box, but then it should be ready for deployment when the weather gets a bit warmer. Yes, I am waiting for spring weather. It may be variable, but I think I can find some warm and dry spells to play with antennas.

We have got more sunspots than I have seen in several years, and we are getting more daylight, so the HF propagation is already better than I have seen it in years. Good times for HF QRP operation ...

The Higher HF Bands Are Good Again.

 Now that we have more daylight in my area (55 deg. N), the propagation on the higher HF bands is improving again.
On top of this, the solar flux numbers have been above 100 for several weeks, with very few days below 100 SFU, I is now about 60 days ago we had no sunspots visible. Cycle 25 has started in earnest.

In my 5W challenge I have now had QSOs on the 10-12-15-17-20-40, and 80m bands.

Testing the SWR with my 5-band dipole showed that it is also useful  for a few more bands than the design frequencies - 10-15-20-40-80m. The dipole can operate on 4-6-12 and 17m. SWR is too high on 30 and 60m, and far too high on 160m. But not bad to be able to operate 9 bands on a 5-band antenna. This may change when I get the feed point higher up, as it is less than 4m above ground. I will have to improve the HF/MF antenna system, so I can include the remaining bands, and maybe try out the 630m band, or the 2200m band.

Last night I made what I refer to as a real CW QSO on 80m. F6BBQ with much more exchange than calls and report. Nice and moderate tempo, perfect for my modest CW capabilities. 

As it is right now, I am using the IC-705 for all the 5W QSOs. When I add an antenna for 30m (planned as a 1/4 wave ground plane), that should be usable on 10m (possibly with a tuner), 6m and 4m on thr 3rd, 5th and 7th harmonic. Not ideal, but probably slightly better than the performance of the low dipole on 10-6-4m, until I can get my 4-6m Moxon rectangle assembled and mounted.

The 30m vertical could be expanded to other bands with parallel (band) elements. This antenna would most likely be used with the IC-7300, with higher power on 4 and 6m, and likely set to 5W on the HF bands. Spring is allowed to begin, but I will probably have to wait another month here.