472kHz transverter fault

Years ago, finding a fault would have been easy. Now, even in small steps, it is exhausting and hard. 

I think the issue is that the oscillator has stopped for some reason: I can detect nothing at 3.2MHz on a nearby RX.  I shall look again at the weekend as now I am so so tired! Just a few minutes is so taxing now. 

This may be as simple as a dry joint. I guess the first thing to try is retouching all the solder joints in the oscillator. It is most likely to be this. I had a diode probe, but I have not seen it for years! I guess I should check the DC volts around the oscillator before doing this.

In the end, the aim is to TX again on 630m QRP. Before the fault arose my measured ERP was just under 10mW. This regularly was spotted on WSPR in Norway.

472kHz WSPR QRP TX

 I really should try to find the fault in my 472kHz transverter. 

At first, I thought it was my earth-electrode antenna, so I completely replaced the wire. The output FET was replaced. 

If my brain was less foggy I am sure I could get to the bottom of it and find what is wrong. With 10mW ERP (measured) it was regularly making it to Norway. 

There are a lot of people monitoring, but few on TX.

See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/630m-472khz-transverter .

472kHz WSPR RX

At 1814z, I QSYed from 10m FT8 RX to 630m (472kHz) WSPR RX. So far, nobody spotted. I am using the earth-electrode "antenna" in the ground.

UPDATE 1943z:  Still no spots.

Last evening on 472kHz WSPR RX

The map shows the stations spotted last evening on 472kHz WSPR RX. 

472kHz WSPR RX

Since about 1805z I have been on 472kHz WSPR RX using the earth-electrode "antenna" in the ground. 4 spots so far this evening.

UPDATE 1946z:  Swapped to the Wellgood active loop RX antenna to compare against the earth-electrode "antenna" in the ground.  The active loop is only 1m across and just stuck to the shack window.

UPDATE 2103z: After an hour on the active loop without spots, I have gone back to the earth-electrode "antenna" and immediately spotted G8HUH (250km) and 2 French stations. My conclusion is the ground-electrode "antenna" is somewhat better. By how much is not clear. With the active loop optimised in position and direction I think the difference might be smaller.

UPDATE 2118z:  More spots, suggesting the earth-electrode is several dB better than the active loop in its present configuration.

UPDATE 2218: 7 unique stations spotted this evening. The latest is EI0CF (602km).

UPDATE 2240z:  QRT. 

472kHz (630m) WSPR RX

Since about 1930z, I have been on 472kHz RX using the earth-electrode "antenna" in the ground. So far, 3 unique stations spotted with the furthermost EI0CF (602km). I am just using the earth-electrode straight into the FT817ND with no attempt at matching.

UPDATE 2020z:  6 unique stations spotted with the furthermost SM6NOC (1056km).

472kHz (630m) WSPR TX activity levels lower?

 Maybe people are using different modes or it is still too early in the season, but the impression I have is there are plenty of monitors on WSPR RX, but fewer people on TX. Usually I am on QRP WSPR TX, but am not yet.

472kHz (630m) WSPR RX last evening

Just 2 unique stations spotted on RX last evening, both in Germany. Disappointing. 

UPDATE 0730z: Doh!! It helps if you connect the correct antenna! The above were with the 10m antenna connected by mistake! I shall try again this evening to see how I get on - this time with the correct antenna!

472kHz WSPR RX

This evening I am on the earth-electrode "antenna" in the ground. It is now 0755z and I have been on for about 15 minutes, but nothing yet spotted.

UPDATE 21020z: So far, just DC0DX (467km) spotted several times At the moment he was the same strength (roughly) as on the active loop. Does this mean they are similar in gain?

630m (472kHz) WSPR RX using the indoor active loop

 At the moment, I am on 630m WSPR RX with the Wellgood active loop. So far no spots.

UPDATE 2136z:  Still no spots this evening. I have to turn things off soon too and go QRT.

472kHz WSPR RX

 As last night, I am on 472kHz WSPR RX with the Wellgood active loop with the 1m diameter loop indoors on the shack window. It is now 1857z and, so far, no spots.

UPDATE 2136z:  No spots this evening. Very disappointing. I may QSY.

472kHz WSPR RX with the Wellgood active RX loop

Last evening I was active on 472kHz WSPR RX using the Wellgood active loop RX antenna. This is very similar to the Wellbrook active loop. I swapped my X80 HF vertical for one. 

In all, just 1 station was spotted - DC0DX (467km) - with the 1m diameter wire stuck to the window indoors. Noise levels are low. This is my first outing on 472kHz RX for some while.

I may try again this evening.

See https://www.george-smart.co.uk/projects/wellgood_loop/ .  George designed this as he was trying to mend his Wellbrook loop. 

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.

Winter MF plans

Well, that was a non-happening! 

One of my plans for now was an E-field probe in a tree for 137kHz and 472kHz RX. We had the tree lopped, but the E-field probe is not up. I replaced my earth-electrode "antenna" in the ground, but my 472kHz transverter does not work, so I am restricted to 472kHz RX only.

Maybe next winter, I shall have more luck!

See https://sites.google.com/site/g3xbmqrp3/mflf/winter .

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.