How few parts?

One of the aspects that I enjoyed was seeing how few parts were needed to make QSOs. This is one of the simplest circuits.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-xbm80-2 .

80m FETer transceiver

Years ago I was inspired by a circuit for a 40m transceiver by W2UW who is now a SK. My challenge was to see if I could make an 80m version with even fewer parts. 

This is a complete transceiver using just a single FET and very few components. It is detailed on my website.

FETer transceiver (2008)

This was another of my attempts to get something for nothing! 

It worked remarkably well, but I struggled with netting the RX onto the TX frequency so I was afraid of clobbering someone else. It was an adaption of a circuit for 40m by W2UW but made even simpler. It appeared in SPRAT some years ago. 

Some have duplicated it and achieved some remarkable DX.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-feter-transceiver .

Crickey - 2008! I must be old  HI 😀

Someone else trying my designs

 It is always good to see others trying their hand at my designs. DX Explorer has a video of him breadboarding my 2 transistor 80m transceiver. My designs are always a starting point. Pretty sure you will be able to improve them!

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-xbm80-2 .

What next?

 As I mentioned in an earlier post today, 630m WSPR seems to have "gone off the boil" and I may try something new over the spring and summer. 

I want to try 8m QRPP WSPR using 10mW and ISM rules (open to anyone in the UK without a licence, possibly in your area of the world too?).  This is mainly a daylight challenge.

Is there a new nighttime challenge? A band that remains good at night. Possibly 160m or 80m using the earth-electrode "antenna" in the ground? I could try FT8 on these bands perhaps.

80m QRP FT8 (Tuesday)

My 80m QRP (2.5W) has been on for the last few hours. My "antenna" is the (almost invisible) earth-electrodes in the ground on which the match is very good. I do not know the ERP on 80m.  2 QSOs have been made with one being PE4BAS, Bas, (450km). Results on TX and RX are far exceeding what I expected. My furthermost spot on TX is UN7MAU (3446km) - quite amazing.

UPDATE 2015z:   QSYed to 630m QRP WSPR.

How simple can you go?

This has been on before, but I make no excuses for posting it again. One of the challenges in amateur radio is to see how simple a complete transceiver can be made that really works. This is just one possibility. There must be many others. My main issue was adjusting the RX to be precisely on the TX frequency. Maybe you have some ideas?

XBM80-2 80m ultra-simple rig

This has been on before, I know.

Some years ago, I wanted to see how simple one could make a rig that actually worked. There is no doubt at all that the rig can be made better with more experimentation with values and other things, but I was quite surprised that something this simple worked.

Please do not (ever) be afraid to use my designs as starting points. If you can make something better, great. If it totally fails, just start again! 

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-xbm80-2 .

80m QRP FT8 using the earth-electrode "antenna" in the ground

80m FT8 spots of my QRP using the
earth-electrode "antenna" in the ground

As I managed to match the FT-710 to the earth-electrode "antenna" in the ground, I was on 80m QRP FT8 early last evening and again now. So far, 60 stations have spotted me. It certainly works! 

Later, I may try calling into the CDARC (Cambridge) 80m net.

UPDATE 1000z: I tried to go on the CDARC 80m net, but heard nobody. Noise level was S9, so I QSYed to 10m FT8 instead on the FT-710 at QRP level. Plenty of spots on TX and RX.

80m FT8 tonight?

Just might try 80m FT8 TX this evening after dark when 10m is no good. It means matching the FT-710 to the earth-electrode "antenna" in the ground and setting WSJT-X for use with the FT-710. For the last few days I have been using the QDX.

UPDATE 1606z:  As 10m does not exactly look great, I might swap to 80m FT8 quite soon.

80m FT8 (Tuesday)

As 6m was so poor, I QSYed to 80m FT8 using the earth-electrode "antenna" in the ground. Although I am receiving spots of my signal from right across Europe, it says I am receiving none. This is rubbish as I can see loads of stations locally. Either there is a delay with uploads from me or, more probably, my spots are not getting to PSKreporter. Shortly I shall do reset to see if this cures it.

UPDATE 1922z:  The reset did the trick with lots of spots on RX. On TX 36 unique station spots of me so far.

UPDATE 2119z:  112 stations have spotted my 10W 80m FT8 TX this evening. Now QRT on all bands.

80m FT8 (Monday)

 At 1255z, I moved from 160m FT8 (no spots) to 80m FT8 using the earth-electrode "antenna" in the ground. The FT8 frequency on 80m seems to be 3.573 MHz.

80m FETer transceiver

One of the challenges in amateur radio is how simple can you make a rig that really communicates? Some years ago I designed and built this unit for 80m CW that appeared in GQRP SPRAT. It is one of the simplest transceivers you can make. It really works!

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-feter-transceiver .

How simple can a rig be?

This was a challenge I wanted to have a go at. This is probably one of the simplest transceivers one can make. My inspiration came from a 40m rig by W2UW who is now sadly a silent key. My wish was to make it even simpler. My main issue was netting. The RX worked well. This appeared in GQRP SPRAT, although I cannot remember when.

There is a video on the website.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-feter-transceiver .

How simple can you make a transceiver?

Many years ago, I built the XBM80-2 80m CW transceiver. It never got cased, but shows how simple a transceiver can be! Somewhere recently I was told that it is a good idea to keep DC from hitting the crystal earpiece. If this is the case, it is probably worth adding a DC blocking capacitor between the audio transistor and earpiece. I have no idea if this is an old wive's tale or fact.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-xbm80-2 .

80m FETer transceiver

It seems like yesterday, but this was designed in 2008. Starting from the 40m design by W2UW (SK) I wanted to see how simple a transceiver could be made for 80m. The result was the 1 FET FETer transceiver. My main issue was netting on RX. 

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-feter-transceiver  .

Ultra simple 80m Transceiver

 

Just how simple can you make a transceiver that actually works? This is on my main website. I hope it gives you some ideas.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/80m-xbm80-2

80m FT8 RX (Sunday)

As 10m is closing, I have QSYed down to 80m FT8 RX using the Wellgood active loop on the shack window. It has been on for about 10 minutes and, so far, 28 stations have been spotted. The furthermost is supposed to be in Iran, but I suspect this is a wrong QTH locator.

80m FT8 RX (Sunday)

As 6m is quiet here today, I have QSYed to 80m FT8 RX with the indoor Wellgood active loop. So far,  80 stations spotted. The furthermost is UV3IK (2699km).

UPDATE 1937z:  267 stations spotted.

UPDATE 2130z:  474 stations spotted on 80m FT8 RX (see map).

80m FT8 RX last evening and overnight

Last evening and overnight I was on 80m FT8 RX with the Wellgood active loop on the shack window indoors. 796 stations spotted, but nothing from the Americas.

The Wellgood active loop is working really well. For RX this antenna is perfect: all I have to do is change the WSJT-X band and the RX frequency.