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?)

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.

QCX Test and Ideas.

 I got the receiver checked. 

Sensitivity on 30m looks good. a signal from the generator at -130dBm is clearly audible. at -135dBm, it's barely audible. This looks quite good for the 10MHz band. 

The audio filter sounds good, with a bandwidth of about 400Hz. That works nicely for me.

I have not yet gone through the alignment process, but I should do that before mounting in a casing. It is probably well adjusted by the previous owner, but it does not hurt making a check. 

Now I need to add an AGC circuit (yes, it's necessary to protect my ears), and use a suitable box. I am likely to add an audio amplifier for use with a speaker.

I will need to move the display, the AF gain potentiometer, the rotary encoder, and the connectors.

I may build a power amplifier to get the level up to about 20W, making this a neat 10MHz CW transceiver.

I am likely to try using a dedicated 10MHz antenna, but initially I can use my 30m long wire antenna.

Rally, "Amatoertraef Fyn". QCX PCB.

 In the past week end I went to the annual HAM radio rally, "Amatoertraef Fyn".

There are a few presentations, and a license exam at the event, and of course a flea market.

I was close to get a MCRF SDR, but passed on that.

At some comissioned stand there was a neat little thing:

- An assembled QCX transceiver (CW single band, with the option for transmitting WSPR)

- An assembled filter switch board for 5 filters

- 6 assembled low pass filters for 6,10,15,20,30,40m

Not a bad catch for DKK 200 (about $30)

At the rally no one knew the band that the transceiver was built for. someone said 15m, but looking at the toroid phase transformer that looked like it had too many windings. My guess was 20 or 30m.

Time to look at the stuff:
As I brought it home, I found that the PCB still had some solder flux residue, but otherwise the soldering work looked good. A bit of cleaning with isopropylene alcohol and a toothbrush cleaned that up, and the test begins.

Switching on the transceiver starts up on 30m, as shown on the LCD display. A quick TX test shows about 2W output (a bit low for the 5W spec, but as there is no cooling of the PA transistors this should work nicely I will leave it at that. The TX test was easy, as there is a spring/microswitch on the PCB, so I could just key the TX.

The TX frequency was shown as 50Hz off on my TRX tester, so I went into the adjustment menu and fot the synthesizer reference oscillator frequency adjusted. The TX is now within +/- 10Hz of the nominal frequency. 

This will work perfectly for CW work. For WSPR work the reference oscillator should probably be replaced with a TCXO, so it remains stable enough to 1-2 Hz.

The only serious draw back of the original QCX is a lack of AGC function. However, there is an add-on for this, so I should order the kit PCB for that, and for the other two QCX+ kits I have already, and should start building (for 20m and 60m).

New (Old) Radio in the Shack.

 I just picked up a bit of a museum piece in the week end.

On the local ham radio site someone sold a Heathkit HW-9. Yes an oldie. 

This one had a WARC band expansion, so yes, 8 bands available. 

Running abpout 3W on 10m up to 4-5W on 80m it is a capable QRP radio.

The set does need a bit of maintenance. Switches are a bit unstable, although the volume potmeter sounds OK. A fresh alignment will also be a good idea, as the (analog, of course) frequency dial is a bit off.

For now I set up the HW-9 as a receiver (without connecting a key), with the audio output connected to a computer speaker. Using the radio for transmitting will come later, after the fresh alignment.

The only real drawback for me is that the tuning is a bit fiddly, I have got used to modern rigs with a nice slow tuning, but this one will do nicely.

Sensitivity is sufficient on all bands, as the noise clearly increases when the antenna is connected, even on 10m. Selectivity is sufficient for my use. Wide is about 1kHz at 6dB and narrow is about 250Hz. The narrow filter is audio based.

CW Filter for FT817.

 Going through some of my stuff I found something very interesting in a box with crystal filters and ceramic filters: Two 455kHz Collins mechanical filters, bandwidth 500Hz for CW, for the FT817.

One is now mounted in one of my 817s, and is working fine. That one is likely to be used as back-end for the QO-100 receiver system. I think I will use another one for my uplink system. As that is TX only I will run that one without the filter.

I do have a third one with a defective PA. I will likely use that one as a base for transverters, for both home and portable. so I can run 4m and microwaves on that one. I will need to bypass the PA module and make some control circuitry for that one. The second CW filter will likely go into that one.

Mounting the filters is easy, it's a simple plug and play. I like to get those small transceivers running, as they draw much less power than the "big radios", like the IC7600 and others.

Second Test on 23cm FM.

At yesterday's test it turned out that the antenna at the other end was not well connected. He got that tested and fixed today

Today's test was with a small improvement from my side, too.

I mounted the X5000 antenna on top of a 4m long mast, with 5m of cable, so today's test was still an outdoor expedition in the garden. On my end of the cable I again used the ancient Standard C710 transceiver. I was just holding the mast/antenna for this experiment, so the antenna moved a bit during the test.

The output power of the C710 is just 300mW on 23cm (1W on 2m/70cm). Distance is about 6km.

This time I heard the signal immediately, at best with a signal of about S5 with his 10W. When I replied I got a report with some fading (according to the antenna position), up to S3. Not bad with just 200-250mW at the antenna.

I hereby consider this a successful test.

I intend to make some more tests with the equipment portable. Find a relatively his spot, and repeat the experiment with just the built-in antenna of the transceiver. Line of sight should not be too difficult, even with 300mW. A test with a small external antenna out there should provide some QSOs

In any case I have made the first 23cm QSO as OZ9QV in more than 30 years.

Now comes the building of the home station and antenna. I do have something to work with.

The IC910 will likely be the main station with a horizontal antenna. The TM741 does FM only, and could be used with the vertical. I have an old transverter that should be tested, and possibly be used for portable work. Yes, I have collected a bit of stuff over the time.

As I have long cables, I expect to use receive preamplifiers as a first improvement, then later some power amplification near the antennas. I have no plans for making big antennas for day-to-day work and a bit of DX, but I stick to the saying that a small antenna is a lot better than no antenna at all.

Small Solar Power Update and More.

 The output from the solar panels has been very low the last several weeks, actually most of November.

I can hardly power my IC703 all day with the current solar input, even if it has improved a bit with the new MPPT charge controller. Some more solar panels should be mounted, but working outside in near freezing temperatures is no fun, so it may have to wait until spring, or if we get some mild and dry days. 

For just monitoring of the low HF bands 20,30,40,60,80m I should use the small Chinese built HB-1B CW transceiver when not at the radio desk, as it uses less power than the 703. The spectrum display of the 703, after all, is only useful when I am there looking at it ;).

With the current very high price for electricity I am looking more at reducing power consumption for the shack. The stand-by/monitoring system has been reduced at the moment until I can get some really low power gear built and/or put to use. Yes, there are options.

Then there is the heating. 

Recently I got an air-to-air heat pump mounted, and now it is finally connected to mains power in the correct way. Yes, I had the electrician here, and at the same time I got an outdoor connector made for charging my new "toy car" (yes, fully electric, running on batteries).

It does look like the mains power consumption is lower than last year, in spite of the fact that I used gas heating last year, and electricity to power the heat pump this year. It will be interesting to see how things will work when I get more solar power up and running. I am aware that going off grid is not possible with the garden I have available, especially in December/January, but any reduction of mains power usage is welcome.

CQWW CW on Solar Power, and My Challenge.

 The past week end I was very active on the radio front.

While I do not plan to send in a log, I made about 150 QSOs, giving many stations points for the CQ WW CW contest. All this happened with just 5W output, and the vast majority was done with my solar power/battery system.

Since the solar power input has been quite low the last few weeks, all the radios were connected to mains power in order to let the battery re-charge. At the same time I did not work too much radio.

After a few QSOs in the contest I decided to make this a mainly solar powered event for me. The IC-705 was reconnected to the solar power system and I worked all through the week end, with some battery energy to spare.

My QSO count with 5W this year is now 460. This means that the challenge of working 365 QSOs this year with just 5W (and no weak signal digital modes) has been met.

Now I extend the challenge to 365 QSOs this year with solar power (as well as 5W). This will be an estimate, as I did not count exactly when I started using solar this year. My preliminary estimate will be that I may have met that challenge, too, but I will work some QSO for the rest of the year. I expect to be fairly sure to meet the challenge this year.

Now what will be my personal challenge for next year? I see a few possibilities.

- maybe with an expansion of my solar power it may be possible to run the main part of the station on solar, with the exception of high power amplifiers. We shall see

- maybe I should make my first QSOs on the microwave bands (everything above 1GHz)

- I *should* finish some more kit building

- maybe I should build a more fully home brew TR/RX just for one band, and work some QSOs with it

- maybe run a challenge with even lower power, allowing for the use of weak signal digital modes

5W/365/2022 Challenge, And a Surprise.

 Here is a small update on my personal 5W challenge, attempting to work at least 365 QSOs in 2022 with just 5W, and not using weak signal modes, i.e. CW,SSB,AM,FM only.

The status right now is 239 QSOs. 

Several of the QSOs have been on 29.6MHz FM in the last few weeks, so I am not complaining.

By far the most QSOs have been made with CW, and a few with SSB. All bands from 80m all the way to 6m have been in use.

Tonight I had a surprise. I was checking 30m, and heard a decent signal, about S6, from FY5FY He was not having a pile up, but stations calling most of the time. When I finally tried to call, I made it in just 3 attempts. Not bad for 5W in a low hanging wire in the garden.

Who knows, maybe this autumn I will make more, as I expect the F2 propagation on the HF bands to improve from now on, as we are already in the late summer season.

Taking into account that I have not been particularly active, I should fulfil the challenge this year.

If I do that, I will make up another challenge. Maybe a single band with an optimized antenna.

Since we are on the upward slope of solar cycle 25, I should probably get up a decent antenna for 6m, as I have not had much time in OZ to work on 6m with F2 propagation. Who knows, maybe already this year ?

10 FM QSOs, and the HB-1B CW Transceiver.

10m FM. 

Having a receiver running on 29.600 FM gave results today.

Twice this evening French stations were coming in with S9 signals, so QSOs were attempted calling them with just 5W, as a part of my 5W challenge this year. Both stations came back and I had two real QSOs, as I call them. exchanging more than just reports.

The sporadic E (Es) season is still going on, and 10m has been quite good today. Yes, it is up and down, but there is a reason we name it "sporadic".

HB-1B transceiver.

Also I did some listening with my small Chinese CW transceiver, the HB-1B transceiver for 80,40,30 and 20m. The sensitivity is absolutely sufficient, on 40 and 80 I usually have the attenuator switched in. As the TRX has only about 5W output the sensitivity is not all too critical. 

The variable crystal filter works nicely, but the AGC is not quite as good as I would like - it has a slow attack, but it does give some protection against signals that are very strong. Most of the time it actually works well enough to listen to (not all too strong) signals. I need to be able to extend my CW keyer "distributor", so this radio can be added to my CW system. 

This could be a nice addition to use in my 5W challenge on the 20-30-40-80m bands. I should probably make myself a diplexer, so my 10-15-20-40-80m dipole can be used on the lowest bands (40 and 80m) with the HB-1B, and another transceiver on 10-15-20m simultaneously. Long term I might make some more multiplexing, so the antenna can be used on all 5 bands (plus 4 and 6m) with different transceivers, or receivers .

30m Wire Antenna Update.

 The 30m long piece of wire has found its place for a while.

The feed point is placed 2m high at the end of the out-house under an apple tree. It then goes up through the tree and lead to the second apple tree - the largest in the garden, then down to a smaller tree where the end is attached. Most of the wire is about 5m above ground, not particularly high, but definitely better than 1m above ground. 

The antenna now has a counterpoise added, about 50m of wire, about 2m above ground (and lower).

The system works nicely on 30m, and does not need a tuner when operating from 80 - 6m. On the resonant bands of the dipole, the dipole mostly works better, but on 20m in particular the wire gives signal mostly equal to the dipole. On 30m the dipole is useless, as it is not resonant at all, and the wire works nicely. A TZ station (Mali) was coming in nicely with up to S9 signals, but 5W was (as expected) not sufficient to break the pile -up. I will have to try again when signals are good, and less stations are calling.

The present set-up of antennas and transceivers for the 80 - 4m bands is now as follows.

IC-705:  Wire antenna, workable on all bands 80m - 6m.

IC-7300: Dipole working on 4,6,10,15,20,40,80m

IC-7600: The old R-6000 antenna running 10-12-15-17-20m, and the 6m part of the V-2000 antenna.

IC-7100: A vertical Sirio half wave antenna for 4m, mostly used for the local FM traffic.

HF Dipole Improved.

 My HF  dipole antenna for the IC-705 has been hanging very low for quite a while. Even then my 5W (mostly CW) challenge for the time of the year is on track.

Yesterday I made an effort to raise the feed point for the "inverted V"from 3.5m to just over 6m, just at the top of the largest apple tree in my garden. It can be brought higher, but for now it stays there, because some of the wires are somewhat entangled in the branches of the tree, and I have not yet un-tangled them.

The antenna is a Diamond make, 5-band dipole with one branch for 10 and 20m, and the other for 15 - 40 - 80m. It is likely that I can add 30m, maybe even 60m to this antenna, as I have some coils from a previous antenna. But this will be for later.

The result? It may be too early to say, but tests yesterday indicate more band noise on some bands.

First of all, the resonance frequencies are a bit high on the bands, mostly in the SSB parts of the bands, so the antenna is too short. I will have to "cut on" some wire (yes, I know, add a bit of wire, but I couldn't help playing with the words)

10m has not done too much, neither has 15m.

On 20m I have had clearly better signals, and it looks like more stations than before are coming back to my calls.

On 40m the band noise is clearly higher, as are the signals. Same for 80m. Some CQ calls on 80m gave a QSO to SP3CW last night.

This concludes the first stage of my antenna maintenance and improvement work, there is a lot more to do.

Solar Power Update.

 Today I made the latest update to the solar power system for the shack.

The system now consists of a battery capacity total of 120Ah nominal, 4 pcs. 12V / 30Ah batteries.

Additionally, the 50W panel has been replaced with a 100W panel. The intention is adding another 100W panel, so the battery *can* be charged with a peak current of just under 20A. In the summer part of the year this should be sufficient to run some of the monitoring receiver systems 24/7. For the winter season a back up system using mains power in the low light solar periods should probably be added.

A higher current rated solar charge controller is also added. The previous one could only handle 10A charge current, the new one handles 20A, corresponding to 2x 100W solar panels. The system should operate within safe parameters. I do have the second 100W panel, so it is a matter of making a good mounting system.

At the moment this system powers my IC-705 fully, and more should be possible:

1) If the voltage drop from inside to the outdoor QO100 PA at the dish is not too high, the second use would be adding this with a switch in the shack. This is necessary as there is a current draw of somewhere about 100mA from the PA, as it is just using a WiFi ("8W") booster that has a DC/DC converter and is also active in "receive mode". It uses a very fast "HF-VOX" transmit-receive switch, so it is usable with SSB signals. The current power supply for this is using an extra DC/DC converter. This way the PA can be mounted in a smaller box closer to the feed antenna.

2) I located an adapter for cigarette lighter connector, so now it is possible to connect the hand-held 10m transceiver to use as a 24/7 monitor receiver for the FT8 frequency on 10m.

3) A small CW-only transceiver with <= 50W on the 80-40-30-20m can be used for mostly monitoring on one of those bands

4) I have crystals for 7074kHz (40m FT8) and 14074kHz (20m FT8) that could be used in simple receivers for monitoring those bands. Other options for building simple receivers for other bands are available.

5) Some "transistor radios" with SSB function can be used on other frequencies not covered by crystals available to me, and for some broadcast frequencies. This requires some extra voltage regulators as their voltage requirements vary from 2 - 4.5 - 6V, maybe others.

Long term I intend to make a separate solar power supply system for the QO-100 system, and a system for lighting, and maybe later some electrical tools.

In the past week I also found some, not too expensive, solar panels. 1 100W panel and 5 50W panels.

I should now have solar panels for peak power of up to a total of 600W. I intend to find more and looked a bit around. I could find some panels similar to the new ones I got this week in Germany, but as far as I can see, a "local" (I can drive there and pick up) has some 280W panels for 24V systems.

When I get those I will definitely need some high capacity batteries for storage. I have been looking into this, and the best solution - long term - looks like using LiFePO4 type batteries. Longer life time/more cycles possible than with lead-acid (gel) batteries so all-in-all a lower cost system. This does require better charge controllers, but I think it is worth it.

I am aware that it will not be possible to go completely off grid where I live, but I can, at least,  reduce the cost of energy in the longer term. A combination of mains and solar power will be the way to go here.

First Radio Running on Solar Power. And First QSO.

I have now set up my small 50W solar panel with a charge controller and lead-acid batteries with a combined capacity of - officially - 60 Ah, using two "30Ah 12V" gel batteries. A more realistic estimate, for avoiding draining the battery below a safe level, would probably be about 30-40Ah from a fully charged battery. 

In the summer months I would expect this set-up to power for all activities with my IC-705, so that radio has now been connected to the solar small power system. 

Now I will have to check how the voltage/capacity holds up.

I expect to have the 705 running for about 16 hours per day. The current drain at stand-by is about 300mA, so about 4.8 Ah is expected to be spent, with the transmit periods I would not expect the consumption to exceed 6Ah per day, except if I would be running a full contest, or the like. This should leave sufficient capacity for adding a few (very) low powered receivers for 24/7 monitoring.

When I have tested the '705 system for a few days, I shall see, if I can add more.

The batteries are meant as a large buffer for the solar panel. With the 50W panel I would expect the average capacity of approximately 16Ah per day, probably more in the longer and sunny days of summer, and less on days with heavy cloud cover, but hardly ever going down to zero per day. 

For the winter season I should probably add a bit of charging via the mains power supply. but it needs to be checked. For now I expect to be able to run my IC-705 solely on solar power for many months.

Further, other systems with small solar panels are in my thoughts, like some lighting for my workshop, with a small panel and some low cost, low power LED lights, mainly for finding my way around at night. This may not be so often, so a large-ish buffer battery with a small 20-30W panel should be sufficient for this.

Later, when I can afford it, I do intend to make a system with larger batteries, this time LiFePO4 type batteries. This will need larger solar panels. 

This may become a life long project. I suspect that I cannot become fully off-grid, but I would expect to be able to run some essenstials, like fridge/freezer and some light on solar. Heating is another matter. That may be beyond the limits of what I want to set up in the garden.

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.

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 ...

10m. A Bit Less Active.

 The last few weeks 10m has been a little less active, but with a few days of high activity.

Solar cycle 25 is going rather well. At the moment the solar flux average is ligher than the official predictions, and has been so since the rise of activity started. There are, of course fluctuations, but at present the flux stays above 90 SFU, with periods of flux above 100, up to a peak of around 130. 

It still seems to be above the forecast, and it will be interesting to see how 10m and the other higher HF bands - and maybe even 6m - will behave as we approach the spring equinox.

The 5W challenge is on track. QSOs have been made on the bands 80-40-20-17-15m, and no more qre needed to fulfil the January goal. I will still try to make some more this month.

Another Personal Challenge. QRP.

This year I will make an attempt to get 365 QSOs in the log, all with just 5W output or less - no matter the band.

The most used transceiver is likely to be the IC-705, but other transceivers, either with a 5W power limit or higher power transceivers set to 5W out may be used. e.g. I intend to get the IC-7300 up and running with a 30m vertical. This antenna will also work on 10-6-4m, so I can get some summer sporadic E, and maybe some other band activity going. 

This requires me to build a new vertical. It will be a ground mounted 30m quarter wave with a good amount of shorter radials on the ground. Other bands in between may also be added with extra (wire elements), e.g. 20, 17 and 15m.

Idea Box: More Simple HF CW Transceiver(s).

 Here is another one for the idea box.

While I am doing stuff for much higher frequencies I am still thinking of this in connection with my "one QSO per band with home made gear" challenge. I was thinking of using a kit (or two) for a simple HF CW transceiver using a direct conversion receiver.

Some examples of those kits are the Pixie, the Rockmite, the Frog Sound and the 49'er. I have a box with some of those kits, and some of them should be quite easy to convert to HF bands up to 18MHz without too much loss of performance.

For higher frequencies I suspect that the receiver sensitivity will be insufficient for efficient work on those bands (21/24/28MHz). Here it is probably a good idea to use two kits, one for TX and one for RX, adding a preamplifier for improved RX sensitivity, and possibly a PA for higher TX power.

Each transceiver would be modified to use a SI5351 synthesizer board. This board should be controller (programmed) by, e.g. an Arduino, so I will have to learn another skill: Micro-controller programming. There are libraries and some programs in existence, but the programming skill will come in handy if I want to extend functions.

A simple 28MHz model could possibly be used as base transceiver for transverters to higher bands. This would not need RX modifications and could possibly be using just a simple TRX kit. I am well aware of the lack of CW activity, especially on the VHF/UHF/SHF bands, but a single QSO, or a few, should be possible.

I do have two other kits for CW transceivers, the QRP Labs' QCX+, with components for 20m and 60m. Still need to be built, but that is a matter of finding time to add those.

Do I have too many kits and projects? Yes, but I will not have any time to be bored, that is certain ...

Another one of the ideas stacking up ;)