Back From Holidays. 1296MHz

I am just back from a retreat.

Yes, I went to a retreat. No radio, no news, just going quiet, let's call it meditation.

Coming back 1296MHz has been variable.

With the vertical the band has been relatively quiet, with sporadic signals from the Polish beacon SR1KOL.

Last night it was very strong early in the evening, then got a little weaker.

A check about 0100 showed it very strong again, with very strong radar signals, too, and in addition the two SK6 beacons near Gothenburg cale through quite well readable, along with the Norwegian one in JO59, and the North Jutland beacon in JO57.

No other signals heard, though, but there was definitely trop propagation.

WSPRing to the Scouts.

 On Saturday a big scout camp (20,000 - 30,000 scouts) is starting.

The closest part of the camp is about 1.5km (a mile) from here, and they will have radio activities.

Previously I have participated  in such camps in 1980, 1985 and 1990, and the group I was running radio with, is still active, and I have contact with them.

At this camp there will also be activities on the HF bands, and some local VHF activity.

One of the activities involves transmissions (and reception) of WSPR (pronounced as "Whisper") signals with low power. I have been asked to have a station active, so they always have someone to exchange signals with.

Yes, thee WSSPR protocol is a one way communication, but reports can be "exchanged" via a site like wsprnet.org, and they are planning to have a map showing where the  signals get to, as part of the scouts' activities.

So from tomorrow I will be sending low power WSPR signals most of the day and evenings.

Output will likely be anywhere between 100mW and 5W into a half wave vertical leaning up a tree.

With luck you may receive my signals on 20m WSPR.

Now that I have this up and running, I may continue with experiments with digital modes, running low power on HF, and also trying it out with higher power on VHF/UHF and microwaves. The WSJTX program is an excellent starting point for all those weak signal (not necessarily low power) modes.

Testing FT8 on 10m with my IC-705.

Yesterday I was testing with 5W on 28MHz.

With sporadic activityI worked 5 stations. Propagation was not very good, but it was definitely there.

Best QSO yesterday was 7Q5MP, Malawi. not bad with 5W

Today I am testing with 1W. My CQ has got me 2 responses, but no QSO yet.

The 1W signal was heard by 9K2HN (Kuwait).

Another Morning Tropo on 1296MHz.

This morning around 0500 (0300UTC).

SR1KOL , again. It has been there until now, with some QSB.

LA1UHG, it was gpone when I checked later.

Morning tropo is definitely a thing.

Early Morning Beacons on 1296.

This morning around 5AM local time, I woke up and made a check of the beacons on 23cm. 

The Polsh one was there again (no surprise), and also the two Swedish ones near Gothenburg were just audible, along with OZ1UHF in Northern Jutland.

The best signal was LA1UHG in JO59.

Yes, morning tropo is a thing on 23cm, for sure.

This afternoon the Polish beacon has been up and down, at some time stronger than the local OZ7IGY, only 26km from here.

More Beacon reports on 1296MHz

 The other day I heard the German beacon DM0UB in JO62KK at 360km. This was at a nightly check at 4 AM. The signal was easily readable and quite visible on the spectrum display of the 9700. This is still with the vertical antenna, so the signal must have been very strong. Distance: 360km.

Last night between midnight and 1 AM, LA1UHG in JO59FB came through, also with a visible trace on the spectrum display, at a distance of 394km.

Yes, the Polish beacon SR1KOL has been coming through several times during these hot days, and I am not surprised any more. I wonder how often I can hear it with horizontal polarization. 

Impressive signals with the vertical, I am guessing they would have been near S9 with a small horizontal yagi.

1296MHz. Beacons, Beacons, Beacons.

 This morning at around 7 - 7:30 (5:00 - 5:30) I heard a plethora of beacons up to about 400km away:

Two beacons near Gothenburg, the one on 1296.800 I heard, cut could not catch. The other one, 

SK6UHI in JO57TX was up to 559

LA1UHG in JO59FB was fading in and out, up to 539

OZ1UHF in JO57FJ was quite weak, but audible.

SR1KOL in JO74TE was as strong as the local OZ7IGY.

All this with a monoband vertical. Yes, I do have a preamplifier at the antenna, that helps a lot.

I am impressed, and looking forward to getting a horizontal yagi up.

10GHz Failed. There's Always Another Time.

 I went to the place of the previous test and tried again.

Things went worse than the previous time. We couldn't make contact on 5760MHz. and still no signals on 10GHz.

Well, well. We will try again.

With microwaves there is always room for improvement. In my case, a lot of improvement.

Tomorrow: 10GHZ Test?

 If weather permits, I will make another go at making a contact on 10GHz tomorrow afternoon. The weather forcast looks pretty good at the moment.

A local amateur has finished a setup with a transverter for 10GHz, and wants to test it, so the plan is going a bit up in the landscape and make a second attempt at a QSO with my IC-905. Yes, I need to get the setup tested again, so I know if it's ready to go.

My New Website.

 It's good to have a blog. 

This one is specialized  with respect to radio.

As I have other interests, I am building a website. It will be quite simple, but with a more "modern" look than the web pages of 20-30 years ago, that I made.

The building of this will be slow, as I need time and energy to build and write. For now there are only a few pages, there will be more as I rebuild the site. It is built on my own domain, originally dubbed oz9qv.dk , but it will have content for my other interests, too, in different sections.

I may post stuff from this blog there, and may post some of the new material in both places, where it fits in.

You are invited to take a look, if you like. There is not much there yet, but give it time, there will be more.

First QSO(s) on a New Band: 5.7GHz.

Yesterday evening I went a bit up-hill to make experiments on 2.4,  5.7 and 10GHz.

The place is only 2km from my home, and with aspace to park and set up a portable station.

I was bringing my IC-905 with the 10GHz unit added, and three antennas:

For 2m-70cm-23cm a vertical with a magnetic mount for the car

For 2.4GHz a tiny panel antenna (Hybrid double quad) (10dBi?)

For 5.7GHz a tall and narrow panel antenna, about 18dBi gain

For 10GHz a 22dBi horn antenna.

Modest station, loosely mounted on a  mobile camera support.

I have made tests earlier on 2.4GHz, from a hill with no car access a bit furthe away, and from the place of yesterday.

The first test on 2.4 GHz didn't go well, as I had the antenna mounted with vertical polarisation, and the others were using horizontal. that can happen when you don't look carefully at the cable coming out from the feed point. The antenna was a yagi mounted inside a pipe "radome", so it couldn't be seen as such. Yess, silly me....

Second test was quite sucessful, with solid signals locally, at distances of about 25km, even using FM.

Yesterday's test started poorly, because the vertical on the car was absolutely not working. SWR infinite...

Looks like a bad connector, I will have to check, because it's a useful backup coom.. So no way of discussing the experiments on air.

So a phone call to OZ1GIN, working with indoor antennas on microwaves. Things did work well enough from the nearby hill, (essentially line of sight) so it was interesting to see how the system worked from a less ideal site.

Fist experiment: Test on 10GHz. I could hear the local beacon hidden behind a hill, so my system was certainly working. He could also hear the beacon with the indoor antenna. Trying to point the antennas we took turns with transmitting "beacon" signals and adjust antennas. 

No signals detected from either side. 10GHZ wasn't working.

On 2.4 GHz I was using a considerable smaller antenna than the first test. Signals were weak, but a QSO in CW could be made.

The 2.4GHz system was also less, as in the previous tests the cable was connected directly to the "base" RF unit, and yesterday the 2.4GHz signals went through the 10GHz unit.

There is definitely room for improvement. 

Then OZ4HZ (as agreed) made a test. A QSO with SSB was possible, although with weak signals.

2.4GHz with the smaller antenna was a qualified succes. 

On 5.7GHz OZ1GIN started in the same way as on 10GHz, with sending beacon signals and turning the antennas. After a few tries, where we also needed adjusting frequency a bit, we managed to make a CW QSO, with slightly better signals than on 2.4GHz.

The signals from OZ1GIN had some scatter sound, warbling a bit, I had not expected it on the distance of 25km, but hinking about it, I probably should. There was also some moderate fading.

Then OZ4HZ, working from an apartment block came with SSB, and we could also work a bit better than on 2,4GHz. His signals did not have scatter sound, so the path was probably closer to line-of-sight than OZ1GIN.

This was my first and second QSO on 5.7GHz.

Now it's time to improve the setup, mechanically and electrically. I am fully aware that there is a lot of room for improvements. 

I should also think of getting some setup at home for those frequencies. Limited height and terrain, including neigbour's houses and some trees will put quite some limits on that, but it should be possible to male some occasional contacts, for example via rain scatter on 10GHz. I have some experiments in mind, probably more on that later.

Solid Improvement on 1296MHz.

A little while ago I found a power amplifier for my 1296MHz setup.

This is essentially a W6PQL design with improvements and control/safety circuits by OZ2ELA.

A group had built this as a project, and one of the participants lost interest and sold the unit.

A test showed a solid output of 80 - 90W, enough for my purpose.

Controlling the mast preamplifier through the coax was not available, so I got myself 2 high power bias-tees for 1296MHz, capable of handling 600W.

Now I can bypass the DC control voltage from the radio to the preamplifier, and still use the PA as TX amplifier. This works well, and I am now running 50W on 1296 most of the time, with a drive of 3W from the transceiver.

I do have some cable loss, so often I could hear people who did not use mast preamplifiers at the antenna, but they could not hear me. With the amplifier, now there is a better balance between the local (FM) stations and my station.

There is still a lot to optimize here, mostly with respect to antennas and cable loss, and now the spring is coming, I can get started with that.

At the moment I am using a vertical monoband 1296MHz antenna. 

Some yagi or other directional antenna is in the planning for use with DX (SSB/CW/DIGI modes, or even FM), and I do have some decent cable available for this purpose.

Update Linton LT9100 Handheld.

Some of the others have received the LT9100 and have similar results.

One measured about 50uW (yes fifty microwatts), -13dBm.

It's not that difficult to amplify to a reasonable level, with modules I have. The trouble is that I have to modify the transceiver internally to access the PTT function. it will not be a handheld radio any more, but it will fall into my definition of (partly) home made, as a major operation is required.

It's possible to make a transceiver with low cost and low standby power, e.e. for use with the local repeater. For the price of the HT and the modules I already have, this is a reasonable project.

Handheld Transeiver Linton LT9100 on 23cm?

 A few weeks ago, in a weekly microwave video chat someone mentioned  getting the Linton LT9100 handheld transceiver. It claims to work up to 1300MHz with 5W (Chinese watts?)

A few of us ordered one, and I got mine today, and made a quick check.

When I use it in the house with the IC-9700, it actually does transmit and receive.

Here is the catch. When connected to an antenna normally used for running the local repeater with 1W, this happened:

In TX no signal through the repeater.

In RX, transmitting with the IC-9700, no reception whatsoever.

In other words, transmit power is certainly below 1W, and the receiver is deaf.

Given that the chip in this transceiver is not specified, and filters may be off, I am not so surprised.

Okay, let's try with a 30dB attenuator between radio and a spectrum analyzer, just to be safe.

Oops! Hardly any visible output on 1296. Let's just say that some amplification is needed. A lot of amplification, the output is in the uW (yes, microwatts) range. 

I still need to check receiver sensitivity, I do have a signal generator for the frequency, I need to check if I can modulate it with FM.

That is for another day.

The radio can be easily programmed for the repeater (and other 23cm) frequencies, so the question is, can it be used as a separate transceiver, with a bit of filtering and a good deal of amplification in both transmit and receive mode?

Possibly. There is no connector for external microphone (or speaker) so it will have to be dismantled and modified, so the PTT can be controlled externally.

I will also wait to see the results from other people in the group, and what they think about it.

So, first impressions, maybe not good for 1296. We shall see.

More Solar and Battery Power.

Last year I got a couple of 24V/100Ah LiFePO4 batteries and the plan was to use them as power supply for 24 - 28V power amplifiers, and as extra capacity for my two older 12V/100Ah batteries.

The 12V system has been used with 3x 100W solar panels, and has supplied a few radios with power in the period from mid February until beginning of November last year. In the dark months I needed to help charging from the mains power, but now the same radios can be supplied with solar power again. It's likely that I will add more panels and an extra charge controller or two to the 12V system.

The total capacity of the 12V system is about 2.5kWh, and I have used it with my power hungry IC-9700 and a bit of other radios. It's possible that I will add a bigger 12V battery later, for a capacity of about 6kWh.

Enter the 24V system. The plan is to add the capacity, so I will have a total of about 7 (or 9) kWh at the radios, using a simple DC/DC charger from 24V to 14V, with constant voltage/current setting and some switching control.

Some more solar panels need be added to th 24V system. I have some already, but I need to get them mounted.

I have found some reasonably priced 450W panels, and I will likely add a few of those to the system.

I have a small and a larger power station(s) that will likely be added to the system. Also, I have some LiFePO4 cells, so I can make a 12V, 24V and possibly a 48V system for the workshop upstairs.

A tiny system for lights and audio in the bedroom is also under construction. Yes, there are many smaller and a few larger projects to build here, along with the radio experiments.

Tidying and Birthday Present.

 As the house is a total mess, a massive task of tidying has been started. It will likely last the whole year, or longer. 

The first task was getting down to the surface of the work desk, test bench.

I found most of the test bench surface ;).

Then I had my birthday recently, and I decided to get myself a present.

I have started doing a bit of microwave activity, and I got myself a TinySA a while ago. This measures up to about 6GHz and has a generator for the same frequency range.

It looks like the generator can show harmonic output well over the 10GHz range. Interesting.

So I decided that I should be able to check filters and amplifiers up to the 6GHz range, and purchased the corresponding NanoVNA, got it calibrated with the calibration set that came with the VNA. 

I have created a few presets, and saved them into the VNA:

350 - 550MHz

2 - 3 GHz and 

5 - 6GHz. 

There is space fro a few more, so I will likely add a range for the 3.4GHz band, the 1296MHz band and maybe one other.

The initial test today showed pretty realistic results, so I consider it a success.

Now I can do a bit of experimentation again. There is a plethora of small and big projects for all frequencies, from 472kHz up to 10GHz, at least. The experimentation may be slow, but it's possible.

Small Transceivers and Low Power.

I now have a rather good collection of small, low power transceivers (and receivers)

Some are low cost Chinese builds, some are small kits assembled by me over time.

Some years ago I purchased some "single frequency" (crystal controlled) transceivers (from Ukraine) tuned to the old frequencies used for the JT65 mode. When FT8 took over, the use of JT65 ceased, because the over all efficiency of FT8 is much better, especially because the transmit sequence is 4 times faster, compensating for the lower sensitivity. and the frequency was moved 2kHz up. 

Usually the crystal frequencies can be tuned down fairly easily, tuning upwards is more limited, so I don't know if I can tune the local oscillator (yes, those are superhet transceivers). If I can, I will try that and use them for FT8.

This would make for a very nice, low power (1W) single frequency transceiver on the 40, 20 or 15m bands. Yes I have those three.

Then there are some simple single frequency kits, (Pixie, Rockmite, and others).

I do have some crystals for the 40, 30 and 20m bands for reception of FT8 and WSPR/QRSS frequencies, and I might use those for monitoring those frequencies.

All this is part of an ongoing (open) challenge of making QSOs on as many bands as possible with my own equipment, and expand this with using home built equipment, too.

Until now I have made QSOs with my own erquipment on all available (in Denmark) bands from 160m to 13cm The equipment can do 6cm and 3cm, too, but no contacts done yet.

Contacts with home made equipment has been done on 80, 40, 30 and 20m on HF, and 2m on VHF.

When I use the expression "home made" I include modified equipment intended for non amateur use, and partly home made equipment, like using a home made 2m transverter with my HF transceiver.

Somewhere I have a Pluto SDR "transceiver" that can be used for all bands from 70MHz to 6GHz, albeit with extremely low power, so that one is a candidate for home made equipment on 70, 144, 432, 1296, 2400, 3400 and 5760MHz, with added front ends for the different bands.

I wish I had more time to do all those experiments. (Don't we all?)

1296 Tropo.

 I am reorganising my station, so the activity level is not so high.

Yesterday, however, 1296MHz was open up to a few hundred km.

I didn't make QSOs, but with my omnidirectional vertical monoband antenna I could hear 9 beacons during the day and evening:

OZ7IGY (of course, it's local at 26km, and always audible) - Everyting else is over about 200km

SR1KOL at about 270km

OZ1UHF at 222km

DB0XY at 438km

SK6MHJ at 229km

SK6UHG at 261km

SK1UHG at 416km

LB2SHF at 369km

LA3SHF at 372km

I am pretty sure I would have heard more beacons with a horizontal antenna, but this tells me that propagation was very good.

Yes, a horizontal antenna system is in the planning, probably for spring next year.

NAC on 1296MHz.

Yesterday I was up at the local hill with the '905 to operate a bit in the Nordic Activity Contest.

This time I brought a bit more equipment, apart from the 23cm yagi antenna:

- a tiny 3 band FM handheld, the Standard C710

- a 2400MHz long yagi.

Among a few contacts with SSB on the '905 and the 12 element yagi, with the local OZ4HZ, after the 1296MHz QSO we tested the 2400MHz band.

On 2400.500 we worked a nice QSO on FM with S9 signals noth ways. Now, with the correct polarization and operating from the hilltop, that was a massive improvement from the first test.

The test with the handheld radio was actually quite a lot of fun.

The radio operates a maximum of about 300mW on 1296, and some of the strations in the Copenhagen area had excellent signals. This radio comes with a tiny 10cm long "rubber duck" antenna, so I was a bit in doubt about the range. The first QSO was with OZ1GIN, working with an indoor antenna 2 small yagis, and reported S9 signals from the radio at about 25km. Yes, he was running horizontal polarization, so it was simple to turn the hand(held) for that.

A bit later I tried with OZ4HZ, and again wee had S9 exchanges, and a less local station, SM7FMX, just over 40km away)  came in for another handheld QSO with good signals.

All worked well, and then I noticed that the radio was in low power mode, so all those FM QSOs were actually worked with a mere 100mW. Now, that is fun portable work on 1296MHz.

I will probably try going light-weight portable on the hill with the handheld and a somewhat larger antenna, so everything can be carried in the rucksack.

New Toy: Handheld "Micro" QRP Transceiver.

 Today I received a small (even for my hands) handheld transceiver. 

The price from Ali Express was not too high, about €130.

This rig is based on the uSDX transceiver, but built into a handheld type casing with a rechargeable 1100mAh Lithium battery. 

I consider this Chines radio as a bit of a toy, so if it won't work for my purpose, it's worth the price for experimentation.

No manual included, so I pushed the power button to see what happened. Lo! and behold ...  The thing switched on and showed 14.074 (yes, the FT8 frequency on 20m), ans sound in the speaker. At least it appears to be working. 

Now, how to switch off this thing???

The power-on switch now acted as a PTT switch, so no good. long push (PTT), double push ... nope!

Internet to the rescue (almost) I found that the volume control set to level "0" should switch it off. Not quite ... I needed to push the wheel, and then turn it off.

Okay, at least I would not deplete the battery capacity.

The TRX essentially does what the uSDX does, so I am interested in how it will work with digital modes, like FT8.

This little radio can receive from 500kHz (?) to 30MHz, and is capable og transmitting on all the HF amateur bands. However, the filters are adapted for the 10-15-20-40m bands, and if I want to use it on other (especially lower) bands, I will need external filters. So the first tests will be on those bands.

I need more testing. I have seen a test by OM0ET on YouTube, and that's why I wanted to try it out, as a fun experiment.

OM0ET also has a video describing some modifications that would make the transceiver more useful, so after an on-the-air test, I might try those mods.