I'm surprised anyone noticed the difference !! Alan G3NYK

BBC Traffic Report East Anglia paralysed by mystery traffic jam. 73, Alwyn G8DOH _____________________________________________________ Alwyn Seeds, Director SynOptika Ltd., 114 Beaufort

Strictly buyer collects QTHR First person to offer to make a £75 or larger donation to Medecins sans Frontieres (MSF) and then proves to me they've done it

I guess it might be interesting to attend this free webinar: >>>> quote 5G is now – but what’s tomorrow? Sub-terahertz and terahertz (THz) waves are often seen as the enabler of wireless

Andy, I think you are correct regarding GB3VHF. The Danish beacon-cluster OZ7IGY come a good second . www.oz7igy.dk/ David G4ASR

Andy, Sorry, that was my mistake. I mixed up ISCAT (which is unfortunately being deleted... it’s still being used for microwave aircraft scatter) with JT4 (which is alive and well). In the last

JT4 is still in the latest (a couple of days ago) 2.4.0 RC3 version. It had better remain, as it's in quite widespread use on microwave beacons, being one of teh few modes capable of coping with

A few comments: - not all of the new WSJT modes use gaussian shaped keying... when I asked, K1JT replied that the modes with tone counts greater than 4 did not benefit from gaussian shaped keying

If you think of the spurii as FM sidebands, then on multiplication by 2, for example, the modulation index (assuming it's very small) has doubled, thus a 6dB increase in level, and so

Hi all , Yes my experiments show a 20 log N increase of spurs. 73 Dom

No, it doesn't work like that. Visualise the multiplier as a hard limiter or zero crossing detector: That -30dB 90MHz component adds to the 100MHz signal and periodically shifts the point at which

"When the RF is passed through a frequency multiplier these spurii increase in relative amplitude as the square of the multiplication factor" I found this "interesting" as I would have thought that

Alwyn I have not got hard numbers to hand, but I can compare it with the 23cm beacon, where the beacon is approximately 95dB above noise in 2.5kHz bandwidth and results in a rise

Dear John and Andy, Getting DDS spurs low enough for beacon use must be quite a challenge. At work, all of our DDS based signal generators, including the pricey ones, have quite a few spurs at the -80

Plenty of food for thought Andy, thank you very much. I'm thinking that upgrading existing beacons to retain low phase noise and spurs might be easiest by using a fixed RDDS for frequency

With the introduction of new modes within the WSJT-X suite that use Gaussian shift MFSK, the old technique of switching between several switched tones using either a DDS or Fract-N PLL is no longer

Hi Chris The Chipbank has some 14.5000MHz if that would help. 73, Mike

Slightly off topic and a bit of a long shot but does anyone have a surplus crystal of frequency 14.4975MHz in their surplus stock that they are willing to part with? HC18/U preferred but can accept

Hi, Unmodified they have a gain of about 20dB and NF around 4dB. I replaced all the FETs with MGF4919s on one and CE3512K2-C1 on another. I also converted the 1st stage to single ended. That reduced

Shameless plug and directly link: https://www.microwavers.org/?accessories.htm - and nice UKuG badges still available too Murray G6JYB