IPK London is a personal site, any software downloaded from here can be used but at your own risk. I accept no responsibility for any misfortune you may have.

HF Propagation.

Think of the Ionosphere as the original Wifi, No Cables, No Computers, No repeaters just good old plain nature. With the right propagation for the time of day and the time of year HF signals bounce off of the Ionosphere and back down to Earth again sometimes many thousands of miles away. So on some bands it is possible to make contact with the likes of Australia and the U.S easily. However propagation has to be good and for that we need to know about Sunspots and SFI (Solar Flux Index). Good Propagation predictor sites are Voacap and Predtest

How Long is this Solar minimum going to last?.

At the moment we are on a sunspot low and that is not good for propagation, so much so that it has the potential to close bands off completely. Today it is only 7.8,and the Solar Flux is Max 70 which isn’t far off of the lowest figure you can get of 65-66, they reckon the actual Solar Minimum will be 2018-2019. So hopefully it will be early 2018 where things will start to pick up again, I doubt it but you never know. Great site for checking Sunspot and SFI activity is

Tropospheric Ducting.

This one most amateurs use even if they don’t know it, (Well the VHF/UHF bands users) is Tropospheric Ducting, Yes because it uses the Troposphere not the Ionosphere. I once stood on The White Cliffs of Dover with my little Baofeng UV5R 5Watt radio (you know, that one that a lot of amateurs think of as useless piece of junk) and I was talking to a Dutch amateur on the PI2NOS repeater he was in Amsterdam 178 miles away as the crow flies and absolutely 5.9 either way (if it had a gauge). Now 178 miles with a cheapie Chinese 5Watt radio to me has to have been aided by propagation in some way shape or form. The conditions were perfect for Tropo, there was even a low(Ish) fog across the English Channel. Great sites for VHF/UHF Propagation are DX Info and aprs.mountainlake

Dover White Cliffs, great place when there’s Tropospheric Ducting


Looking for Tropo for VHF? Then best you check out this site Click Here

The Propagation Prediction websites featured here all give exactly that, predictions, I wouldn’t take it all as gospel, but they can give a good indication of what will be the best band to operate on for Dxing. Whilst I know a bit about Propagation my baby is Tropospheric Ducting.

Radio’s like Icom 7300 and 7610, and Yaesu FTDX 9000 and 3000 operate on high power and as they’re HF are designed with long distance in mind. However Radio's like my trusty Yaesu FTM 100 and certainly my Baofeng UV5r are designed for extremely local stuff, mind you the Yaesu is armed with C4FM capabilities. But whether you use a repeater or Openspot for distant contact nothing beats good old fashioned Tropo.

Is it possible to get 147 miles or more on a 50w mobile 2M 70\cm radio? Yes and considerably further. Is it possible to get 100 miles using a 5W Baofeng UV5r? Well yes actually, using Tropospheric Ducting (Tried and Completed three times now)

Tropospheric Propagation

Ionosphere Propagation

This is just a pic, for Current VHF conditions site Click Here

Helpful Radio Manuals

IcomIC 7300

Icom IC 7100

Icom IC7610

Icom ID 5100

Icom Base and Mobile

Icom Handheld

Icom ID 31AE Plus

Icom ID 51AE

Icom ID 4100AE


TS 590SG

Yaesu Radio’s





Icom IC 9100

Still more to be added as I get the chance to do so.

Wot No Sunspots?

I’m afraid it’s that eleven year lull once again, At present VHF/UHF seem to be getting the occasional lift, but with HF it’s few and far between 0 SSN with a SFI of just 69 as I type this, not the best conditions and certainly not the most disastrous either.

On a Field Day? Try these.

D74 E

Firmware and Other Downloads

For Kenwood Products, click Here

For Icom Products Click Here

For Yaesu, Go to their website and Click on Products

I think people know by now that I like the digital modes of the hobby too and have always wondered what what the clearer of the three MAIN modes.

What is best?  Dstar? C4FM (Fusion)? Or DMR?

Today my Yaesu FTM100DE (C4FM Radio) sounded like I have never heard it before. I was listening on CQ-UK  to Hams who decided to switch from the standard digital voice (DV) to voice wide (VW) I thought DV was clear but when I heard VW I couldn’t believe my ears, what a great sound coming out of the speaker.

That’s because VW (Voice Wide) uses the complete 12.5KHz bandwidth as it is not transmitting any callsign or GPS data and boy can you hear the difference, especially on the Yaesu FTM100DE.

The first Digital radio I got was a Retevis RT3 (TYT MD 380 Copy) and as I wasn’t licenced at the time (got it four weeks before I passed my foundation Licence) I had never heard any dedicated Amateur Radio let alone DMR, so I was pretty new to the whole thing after using scanners for around 46 years. I thought my Retevis was the Bees Knees in sound then along came my Yaesu FTM100DE and that sounded awesome just on DV alone. After that came Dstar which I find to be the busiest of them all but also the thinnest sound of them all. (sorry Dstar) In saying that my Dstar radio is awesome too (Kenwood THD74) it is a great radio and you can entirely see why it is the price that it is. But let’s be fair the reason for this is comparison in sound not in radio choice. C4FM is undoubtedly the most richer complete sound of the three, DMR comes in second as it’s not the same as C4FM but a much more complete sound than Dstar that takes the third place. Don’t think I’m putting any of them down as I love them all. To be able to chat across the world is Fantastic and long may it continue