472kHz sensitivity with a signal generator

With the preamp in front of the FT817 I can copy down to at least -127dBm, which is the lowest the generator will go without external attenuators. Without the preamp, sensitivity is at least 10dB worse. Of course, in reality, external noise will set the real limit. On my FT817, the IPO in/out made little difference to the sensitivity. I suppose the NF was being set  by the preamp. It is definitely worth having the preamp (with filtering) in circuit.

I am so grateful to the kind anonymous person who sent me this preamp. Thank you again. I have no idea who you are but I am extremely grateful for your great kindness. There really are some very kind people around.

Sunspots and 10m - Thurs Sept 24th 2015

Sunspot number has climbed again. It is now 95 (K=3) but 10m is again expected to remain "poor". It is your guess how 10m will be today! 

As previous days have shown, there is still some Es about around Europe, (I am sure we'd see even more if WSPR activity was greater) and F2 DX is starting to occur and even my 500mW WSPR is being spotted at some distance again (Brazil and Reunion Is.).

472kHz WSPR RX overnight with preamp

Overnight, I used the FT817 on MF RX with a preamp and the (short) earth-electrode antenna in the garden. Subjectively, the sensitivity is better and I am able to copy stations at better strength. I will do a straight comparison of sensitivity, with and without the preamp, using a signal generator later.

These are the unique station spots given to others overnight. Many stations were copied many times of course:

Unique 472kHz WSPR stations copied overnight

472kHz RX with a preamp

I am currently looking on 472kHz with the earth electrode antenna but with a preamp ahead of the FT817. Tomorrow I will check the sensitivity with and without the preamp at 472kHz using a signal generator. Already I have copied a couple of French stations at good strength.  Overnight I'll leave the system running to see what I copy. I am not on TX overnight, just RX.

UPDATE 2136z:  I managed to dislodge the laptop power lead, the battery was very low and the PC shut down, so no WSPR for some while. All now plugged in again and working. Initial results are very encouraging.

472kHz WSPR RX with preamp - to 2150z

Another good day on 10m WSPR

10m WSPR has been good again with both F2 and Es propagation. Best DX is again a spot by FR1GZ (9724km). 4X1RF has been spotting me all afternoon.This could well be F2.

Unique 10m WSPR spots today

Visible Light Communications

There is a nice precis on Wikipedia about this. It is some time since my health has allowed me to do experiments with light. My special interest is NLOS data comms. That is sending data over the horizon using light.

See https://en.wikipedia.org/wiki/Visible_light_communication .

VW chief resigns - NOT amateur radio

The BBC is reporting that the head man at Volkswagon has resigned. He had little choice. The recent cheating with software in US emissions tests is a corporate scandal of the highest order. I think many in the motor trade,especially those at VW, must be worried about prison.

See http://www.bbc.co.uk/news/business-34340997 .

House Martins at Anglesey Abbey - NOT amateur radio

Anglesey Abbey today

Well, there are still house martins around. We saw at least 6 this afternoon at Anglesey Abbey. These may be the stragglers or young ones. They will soon be gone to warmer climes. We also heard long tail tits and saw a buzzard.

The grounds here are very large and there is always something to see at any time of the year. The picture shows pompoms hung in trees made from old dahlia heads. They dig up the dahlia bed Oct 4th. The dahlias have been splendid for a couple of months.

UK National Hamfest

I recently received this reminder:

"25 & 26 SEPTEMBER : NATIONAL HAMFEST
brought to you by the RSGB in association with the Lincoln Short Wave Club. George Stephenson Pavilion, Newark and Nottinghamshire Showground, Lincoln Road, Winthorpe, Newark NG24 2NY (close to junction of A1/A46/A17). Free CP, TS, B&B, CB, C, SIG, Morse proficiency tests on demand, RSGB book stall, RSGB Services & Committees, DF, FM. www.nationalhamfest.org.uk.

A list of rallies can be found at http://rsgb.org/main/news/rallies/"

VW (and others?) scandal - NOT amateur radio

At the last count 11 million VW cars are involved. VW are in trouble big time and it is all their own fault. The executives and many at the top will rightly have to "carry the can" for this mess up. Surely, they had no need to blatantly cheat? Top executives should have known about this - no excuses!

Sorry, but I have absolutely no sympathy for this unethical business behaviour. They deserve to suffer for deliberately deceiving the public and the testers. It would not surprise me if some senior executives get lengthy prison sentences.

I have no sympathy as there is absolutely no place for unethical "carrying ons" like this in the 21st century. VW should have been above this sort of behaviour. They got caught cheating and they must take the full  consequences. This means fines, cancelled bonuses and prison.