Canadian 472kHz transverter

Allen VY1KX has kindly sent me a photo of the 472kHz transverter he has built. I built my original on copper clad board to ensure a good ground plane. I recommend this as it makes grounding easy. Allen's transverter is in the photo. 

See https://sites.google.com/site/g3xbmqrp3/mflf/472khz_tvtr

472kHz WSPR last evening

Continued monitoring overnight has not been that productive on previous occasions , so I went QRT in the late evening having spotted 4 unique stations. As usual, using the FT817ND and the earth-electrode "antenna" in the ground.

472kHz WSPR RX

At 1844z, I QSYed to 472kHz (630m) WSPR RX. Once again, I am using the FT817ND and the earth-electrode "antenna" in the ground.

UPDATE 2211z:  G0MRF has been a huge signal this evening. Furthermost is LA8AV (1012km).

UPDATE 2300z:  QRT

472kHz (630m) WSPR RX overnight

 Yesterday evening and overnight I was on 472kHz WSPR RX with the earth-electrode "antenna" in the ground. 9 stations were spotted with the furthermost being EA4GHB (1300km).

630m (472kHz) WSPR RX

This evening I am on 630m WSPR RX from about 2045z.  So far this evening, 3 stations spotted with furthermost LA8AV (1012km). Still using the earth-electrode "antenna" in the ground.

472kHz WSPR RX

At about 1930z, I turned on 472kHz WSPR RX using the earth-electrode "antenna" in the ground. So far, no spots. It is now 1952z. 

I notice the noise floor on 472kHz with the PC charger on was S8, whereas with the charger off it is S2. As WSPR bandwidth is only about 6Hz, I wonder what difference this makes? I am no theory man, so I do not know the answer.

UPDATE 2210z:  5 different stations spotted this evening with the furthermost LA8AV (1012km). I shall shortly be turning off the gear.

472kHz WSPR overnight

By accident, I left my 472kHz (630m) WSPR RX on overnight. It was a waste of time as no further stations were spotted that I had not already spotted in the previous evening. As before, using the earth-electrode "antenna" in the ground. 

In future nights I must remember to turn this off overnight or try RX on another band.

472kHz (630m) RX

At about 2000z, I QSYed to 472kHz RX. At first I tried FSW4W, but so far only WSPR has been received. Just F5WK (364km) spotted. Using the earth-electrode "antenna" in the ground.

UPDATE 2122z:  4 stations spotted on WSPR with the furthermost being F5WK in IN99.

472kHz (630m) WSPR RX

It is now 2030z. A few minutes ago I went on to 472kHz WSPR RX. So far G0MRF (139km) and DL1HWK (816km) copied.

UPDATE 2215z: 5 stations spotted this evening with the furthermost being IZ3QQG (1155km). Still using the earth-electrode "antenna" in the ground.

472kHz tonight

Hopefully, my transverter works. I shall try later.

Whatever happens, I intend to be on 472kHz (630m) this evening. If the transverter works I shall go on TX. Otherwise RX only. 

In both cases, I shall be using the earth-electrode "antenna" in the ground, that gave good results on 160m FT8.

UPDATE 2044z:  I tried my transverter again and still no sign of any 472kHz output, so I decided to go on 472kHz WSPR RX only. Just LA8AV (1012km) spotted so far. If I was fitter I might be able to fault find. With my health as it is, I think this is beyond me sadly.

UPDATE 2130z:  6 unique stations spotted on 472kHz WSPR RX with the earth-electrode "antenna" in the ground. Furthermost is SM6NOC (1056km).

No 472kHz TX this season

For the first time in many years, I have not been on 472kHz WSPR TX this year. 

Although the real reason is laziness, I blame it on not replacing the wire used on my earth-electrode "antenna" in the ground. 

Although my transverter puts out about 12W into 50 ohms, my measured ERP is about 5-10mW only. Despite this, I was copied up in Norway most nights last season on WSPR.

Others who have built the transverter have had transatlantic WSPR spots on 472kHz (630m). This is one of the most simple ways of getting on 472kHz TX. My "antenna" might not be the greatest, but it does work and the neighbours, and XYL,  don't even know it is there! 

I have also used the earth-electrode "antenna" on 160m, 80m and 60m with success. It should also work on 2200m TX although I have not tried this.

472kHz (630m) WSPR

At the moment I have not tried 472kHz (630m) WSPR TX for a while as I need to replace the wire in my earth-electrode "antenna". In past winters I have had lots of fun overnight with low ERP WSPR. I really should try again during January, February and March.

I still have a quiet noise floor on 472kHz WSPR RX. With AM on 160m, 80, and 40m, the noise floor is S8. WSPR being a narrow-band mode seems to do much better.

See https://sites.google.com/site/g3xbmqrp3/mflf/472wspr

472kHz WSPR RX

For about 15 minutes (it is now 1918z) I have been on 472kHz WSPR RX using the FT817ND and the earth-electrode "antenna" in the ground. No spots yet.

UPDATE 1940z: 5 different stations spotted so far this evening. Furthermost was LA8AV (1012km). Next was SM6BGP (994km).

630m WSPR RX

There may be 2 issues with my 472kHz (630m) QRPP setup. 

As mentioned in the last post, I suspect the IRF510 PA device is damaged.  My transverter gives 12W into a 50 ohm load, but the measured ERP is less than 10mW. Despite this, I was able to get to Norway most nights last winter.

There may also be a break in my earth-electrode "antenna". 

As a first step, I am on 472kHz WSPR RX overnight. If this works, it probably means the earth-electrode "antenna" is intact. If this is the case, I may be able get on TX again just by mending the PA device. If this fails, I shall replace both the IRF510 and the wire in the garden.

UPDATE 1830z:  With F and DL already spotted, initial results are encouraging.

UPDATE 2130z:   I think the earth-electrode "antenna" in the ground is fine, judging by results this evening. I shall leave the RX on overnight, although I have spotted far more than I expected.

472kHz WSPR RX overnight

As you may remember, the PA in my transverter has been damaged, so I am on 472kHz RX only. Last night was very disappointing with just LA8AV and F1AFJ spotted here.

Return to 472kHz WSPR TX (less than 10mW ERP)

Using the earth-electrode "antenna" in the ground I have returned to 472kHz WSPR TX.

As the ground is very wet following the storms, it is very likely the ERP is below 10mW and the size of the loop in the ground is smaller than usual. The antenna current measures lower. If the soil conductivity is higher the signal cannot spread out so much as the effective loop area is smaller.

So far, just 4 spots by G0VQH (15km).

UPDATE 1815z: Still just spots from Jenny G0VQH. May later I may get more spots?

UPDATE 1935z:  QRT. Is the earth-electrode "antenna" damaged?

Return to 472kHz WSPR TX (10mW ERP)

After an absence of several weeks, I have returned to 472kHz WSPR TX. My measured ERP is less than 10mW from the earth-electrode "antenna" in the ground.  The output of the transverter is about 12W into 50 ohms, but the "antenna" is pretty inefficient, although better than expected.

Even in daylight I was quite surprised to see 3 unique stations spotting me with best DX spots by G0MRF (139km).

All being well, I hope to stay on overnight.

UPDATE 1206z: So far today, 4 different stations have spotted my 10mW ERP 472kHz WSPR signal.

UPDATE 1835z: 17 stations have spotted my 10mW ERP so far (see table below).

Promising evening on 472kHz WSPR TX (10mW ERP)

Already 12 spots from Norway this evening and spots by 17 different stations!  This is looking very promising.

UPDATE 2235z: 19 stations have spotted my QRPP 472kHz WSPR TX so far this evening. I shall run until well light tomorrow.

Stations spotting me this evening

472kHz WSPR TX overnight

Overnight, I was again on 472kHz WSPR with the 10mW ERP from the earth-electrode  "antenna" in the ground (see post on this "antenna" a few days ago). 18 stations spotted me including 24 by Jan in Norway.

Stations spotting my 10mW ERP 

on 472kHz in the last 24 hours

472kHz WSPR TX (10mW ERP)

A few minutes ago I returned to 472kHz WSPR TX using 10mW ERP from the earth-electrode "antenna" in the ground. So far, 4 stations have spotted me as the table shows.

Stations spotting my 10mW ERP
on 472kHz WSPR to 1655 today

UPDATE 2016z:  Now spotted by 9 stations with best DX PA0LSB (326km).

UPDATE 2233z: 15 stations have spotted me this evening.

Stations spotting me this evening