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A little bandwidth teaser

G8JBJ John
 

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
M0LDP Dave
 

Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave


On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G8JBJ John
 

Thanks Dave, I'll expand in a bit if no one gets it!

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ


On Tue, 26 Jan 2021 at 13:10, M0LDP Dave <m0ldp@...> wrote:
Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave

On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G3WYN Ken
 

Hello John. I know nothing about FT8 (isn't that the one where you use a computer to let you operate your radio?) but Bob, N4XAT was 599 here on CW direct from his little mag loop so who needs a computer anyway? David, WB1EAD did  call you to no avail. I wonder if you were listening today. 73, Ken

On 26/01/2021 13:19, G8JBJ John wrote:
Thanks Dave, I'll expand in a bit if no one gets it!

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

On Tue, 26 Jan 2021 at 13:10, M0LDP Dave <m0ldp@...> wrote:
Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave

On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G8JBJ John
 

Hi Ken,

Regret no, not today. Just gearing up to run a webinar. Thanks for getting David to call. 

As you indicate - and here's a clue - the same is true of CW, though with a key difference.

John


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ


On Tue, 26 Jan 2021 at 14:27, G3WYN Ken via groups.io <G3WYN=btinternet.com@groups.io> wrote:

Hello John. I know nothing about FT8 (isn't that the one where you use a computer to let you operate your radio?) but Bob, N4XAT was 599 here on CW direct from his little mag loop so who needs a computer anyway? David, WB1EAD did  call you to no avail. I wonder if you were listening today. 73, Ken

On 26/01/2021 13:19, G8JBJ John wrote:
Thanks Dave, I'll expand in a bit if no one gets it!

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

On Tue, 26 Jan 2021 at 13:10, M0LDP Dave <m0ldp@...> wrote:
Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave

On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G4UDU Phil
 

It is down to the signal to noise ratio that is required to maintain a communications link.

With SSB you need 8 - 10 dB as an absolute minimum to resolve meaningful speech - CW can be achieved with 2 - 3 dB

FT8 will work down to - 20dB or lower

Look at the dB difference then calculate the power

So take +10 to -20 that’s 35dB.   So 100W SSB + 30dB  + 100kW


Phil G4UDU




 

On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all0

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ
G4UDU Phil
 

OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ
G8JBJ John
 

Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


 

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919


TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd


ᐧ


On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ
M0XYF Berni
 

FT8 is the greatest thing to happen to amateur radio in the 30-odd years that I was away. IMO it has quite simply divided amateur radio history into pre and post FT8 eras. I don't particularly enjoy operating FT8, rather I see it as a marker for the advent of amateur radio 2.0. It's been the perfect disruptor, a conversation starter. Dare I say it, the saviour of the hobby? It re-engaged me with radio and that's why I love it.

I appreciate and respect all facets of the hobby. People need to stop trying to define what 'real radio' is and accept the diversity of modern day radio. I've owned a radio for 18 months, and I honestly couldn't tell you if the microphone works or not. Never used it. Personally I'm interested in the self-study of digital (and by that I mean data) RF comms, experimenting and researching with my 147MHz NoV and ultimately in developing new protocols and technologies. My Icom is just my computers' 100W RF modem. Mind you, I'm equally happy constructing antennas and building other cool projects as well as getting lost in SDR, DSP and GRC!

Berni M0XYF


On 26/01/2021 17:25, G8JBJ John wrote:
Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
G8JBJ John
 

Thanks Berni,

Nicely argued.

Anyone else have any thoughts?

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ


On Tue, 26 Jan 2021 at 22:57, M0XYF Berni <msars@...> wrote:

FT8 is the greatest thing to happen to amateur radio in the 30-odd years that I was away. IMO it has quite simply divided amateur radio history into pre and post FT8 eras. I don't particularly enjoy operating FT8, rather I see it as a marker for the advent of amateur radio 2.0. It's been the perfect disruptor, a conversation starter. Dare I say it, the saviour of the hobby? It re-engaged me with radio and that's why I love it.

I appreciate and respect all facets of the hobby. People need to stop trying to define what 'real radio' is and accept the diversity of modern day radio. I've owned a radio for 18 months, and I honestly couldn't tell you if the microphone works or not. Never used it. Personally I'm interested in the self-study of digital (and by that I mean data) RF comms, experimenting and researching with my 147MHz NoV and ultimately in developing new protocols and technologies. My Icom is just my computers' 100W RF modem. Mind you, I'm equally happy constructing antennas and building other cool projects as well as getting lost in SDR, DSP and GRC!

Berni M0XYF


On 26/01/2021 17:25, G8JBJ John wrote:
Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
M0LDP Dave <m6iqw@...>
 

I think FT8 is a fantastic tool for measuring propagation and perfecting antennas with the minimum of equipment (given PSK Reporter).

However your teaser made an assumption of 50W for FT8 without which the maths wouldn't have worked so I'm celebrating getting it right now the missing variable has been supplied 🍺✨🍻❤️

On 27 January 2021 09:02:16 GMT, G8JBJ John <john.berry@...> wrote:
Thanks Berni,

Nicely argued.

Anyone else have any thoughts?

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ

On Tue, 26 Jan 2021 at 22:57, M0XYF Berni <msars@...> wrote:

FT8 is the greatest thing to happen to amateur radio in the 30-odd years that I was away. IMO it has quite simply divided amateur radio history into pre and post FT8 eras. I don't particularly enjoy operating FT8, rather I see it as a marker for the advent of amateur radio 2.0. It's been the perfect disruptor, a conversation starter. Dare I say it, the saviour of the hobby? It re-engaged me with radio and that's why I love it.

I appreciate and respect all facets of the hobby. People need to stop trying to define what 'real radio' is and accept the diversity of modern day radio. I've owned a radio for 18 months, and I honestly couldn't tell you if the microphone works or not. Never used it. Personally I'm interested in the self-study of digital (and by that I mean data) RF comms, experimenting and researching with my 147MHz NoV and ultimately in developing new protocols and technologies. My Icom is just my computers' 100W RF modem. Mind you, I'm equally happy constructing antennas and building other cool projects as well as getting lost in SDR, DSP and GRC!

Berni M0XYF


On 26/01/2021 17:25, G8JBJ John wrote:
Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ


www.qrz.com/db/M6IQW

Sent from my Android device with K-9 Mail. Please excuse my brevity.
G8JBJ John
 

Thanks Dave.

More good comment.

Just FYI, given that propagation has loads of variables that make it hugely complex, I like VOACAP at https://www.voacap.com/hf/ for looking at possibilities. Here's today's FT8 prediction given the current smooth sunspot number of 18. You'll notice a sweet spot today to VK at around 11:00hrs UTC with predicted 80% chance. Best band is 15m. 20m would be too low. Would be interesting to use on-air data to correlate with prediction over several months.

John
image.png



 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ


On Wed, 27 Jan 2021 at 10:33, M0LDP Dave <m6iqw@...> wrote:
I think FT8 is a fantastic tool for measuring propagation and perfecting antennas with the minimum of equipment (given PSK Reporter).

However your teaser made an assumption of 50W for FT8 without which the maths wouldn't have worked so I'm celebrating getting it right now the missing variable has been supplied 🍺✨🍻❤️

On 27 January 2021 09:02:16 GMT, G8JBJ John <john.berry@...> wrote:
Thanks Berni,

Nicely argued.

Anyone else have any thoughts?

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ

On Tue, 26 Jan 2021 at 22:57, M0XYF Berni <msars@...> wrote:

FT8 is the greatest thing to happen to amateur radio in the 30-odd years that I was away. IMO it has quite simply divided amateur radio history into pre and post FT8 eras. I don't particularly enjoy operating FT8, rather I see it as a marker for the advent of amateur radio 2.0. It's been the perfect disruptor, a conversation starter. Dare I say it, the saviour of the hobby? It re-engaged me with radio and that's why I love it.

I appreciate and respect all facets of the hobby. People need to stop trying to define what 'real radio' is and accept the diversity of modern day radio. I've owned a radio for 18 months, and I honestly couldn't tell you if the microphone works or not. Never used it. Personally I'm interested in the self-study of digital (and by that I mean data) RF comms, experimenting and researching with my 147MHz NoV and ultimately in developing new protocols and technologies. My Icom is just my computers' 100W RF modem. Mind you, I'm equally happy constructing antennas and building other cool projects as well as getting lost in SDR, DSP and GRC!

Berni M0XYF


On 26/01/2021 17:25, G8JBJ John wrote:
Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ


www.qrz.com/db/M6IQW

Sent from my Android device with K-9 Mail. Please excuse my brevity.
G8JBJ John
 

Ken, just looking at the prediction to NJ today for CW, this shows 80% chance. I simulated the lower efficiency of the antennas by dropping the power to 10W. Best time is 14:00 UTC on 20m. 15m might work but the window is short.

John

image.png




ᐧ


On Tue, 26 Jan 2021 at 14:27, G3WYN Ken via groups.io <G3WYN=btinternet.com@groups.io> wrote:

Hello John. I know nothing about FT8 (isn't that the one where you use a computer to let you operate your radio?) but Bob, N4XAT was 599 here on CW direct from his little mag loop so who needs a computer anyway? David, WB1EAD did  call you to no avail. I wonder if you were listening today. 73, Ken

On 26/01/2021 13:19, G8JBJ John wrote:
Thanks Dave, I'll expand in a bit if no one gets it!

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

On Tue, 26 Jan 2021 at 13:10, M0LDP Dave <m0ldp@...> wrote:
Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave

On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G3WYN Ken
 

John, Thanks, Bob was 449 throughout today on CW whilst Barry SM7GDB who was unworkable at 1330 was 59+15 at 14.20  as the net closed. Seem like 20m is the right band for the lunchtime net these days! Ken

On 27/01/2021 12:04, G8JBJ John wrote:
Ken, just looking at the prediction to NJ today for CW, this shows 80% chance. I simulated the lower efficiency of the antennas by dropping the power to 10W. Best time is 14:00 UTC on 20m. 15m might work but the window is short.

John

image.png

ᐧ

On Tue, 26 Jan 2021 at 14:27, G3WYN Ken via groups.io <G3WYN=btinternet.com@groups.io> wrote:

Hello John. I know nothing about FT8 (isn't that the one where you use a computer to let you operate your radio?) but Bob, N4XAT was 599 here on CW direct from his little mag loop so who needs a computer anyway? David, WB1EAD did  call you to no avail. I wonder if you were listening today. 73, Ken

On 26/01/2021 13:19, G8JBJ John wrote:
Thanks Dave, I'll expand in a bit if no one gets it!

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

On Tue, 26 Jan 2021 at 13:10, M0LDP Dave <m0ldp@...> wrote:
Sounds an interesting problem but I don't understand the question. "Comms the same"? What do you mean?

73 de Dave

On 26 January 2021 13:02:31 GMT, G8JBJ John <john.berry@...> wrote:
Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
ᐧ

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
G4UDU Phil
 

FT8 - Well we all have our preferred modes …………




But for those of you that have taken a liking to using FT8 and are pleased with the results you get with respect to distance of contacts with limited power and and antennas

You need to give "JS8 Call" a try - this is a keyboard QSO mode using the FT8 transmission algorithms, so you get the same distance but with the ability to send text to the other station and not just a simple automated report.

You need to read the instructions because there are different speeds of transmission all of which are totally compatible with each other but some work better depending on signal conditions - at its fastest it works something equivalent to around 40 words per minute CW so probably a lot faster than you can type !




And best of all it will run on anything that is  



  • Desktop Linux (64-bit x86_64, deb)
  • Desktop Linux (32-bit i386, deb)
  • Raspbian Stretch (armv7, deb)
  • Windows 10 (win32_64)
    • Windows 10 is the only officially supported Windows build at this time, but the application has been confirmed to work all the way back to Windows XP.
  • Mac OSX 10.11+ (x86_64)




Give it a try and report back here


73 Phil G4UDU
N4XAT Roberto
 

Thanks Phil for the JS8 information.  I will download it and give it a try.

DE N4XAT/Bob
M0LDP Dave <m6iqw@...>
 

Thanks Phil, sounds interesting!


On 27 January 2021 19:25:31 GMT, G4UDU Phil <pgodbold@...> wrote:
FT8 - Well we all have our preferred modes …………




But for those of you that have taken a liking to using FT8 and are pleased with the results you get with respect to distance of contacts with limited power and and antennas

You need to give "JS8 Call" a try - this is a keyboard QSO mode using the FT8 transmission algorithms, so you get the same distance but with the ability to send text to the other station and not just a simple automated report.

You need to read the instructions because there are different speeds of transmission all of which are totally compatible with each other but some work better depending on signal conditions - at its fastest it works something equivalent to around 40 words per minute CW so probably a lot faster than you can type !




And best of all it will run on anything that is  



  • Desktop Linux (64-bit x86_64, deb)
  • Desktop Linux (32-bit i386, deb)
  • Raspbian Stretch (armv7, deb)
  • Windows 10 (win32_64)
    • Windows 10 is the only officially supported Windows build at this time, but the application has been confirmed to work all the way back to Windows XP.
  • Mac OSX 10.11+ (x86_64)




Give it a try and report back here


73 Phil G4UDU





www.qrz.com/db/M6IQW

Sent from my Android device with K-9 Mail. Please excuse my brevity.
G3WYN Ken
 

Nice thread John and all noted about the advantages that narrow band modes have over "ordinary" signals. Amateur radio to me is about making friends over the air and this has allowed me to, following an intitial over the air contact to have face to face meetings with other amateurs in many countries and make long term friendships lasting for many years. Sean EI7CV, Gerry, EI9DZ and Bob, N4XAT are examples of such casual meetings as are the MSARS daily and weekend nets which continue to provide further friends both at home and overseas.

Of course I used to collect cards and awards to decorate the shack but to me these are no substitute for continually talking to my friends over the air and learning more about their lives and hobbies. I remember when SSB was replacing AM more that 50  years ago and the fuss we all made about what was after all just another mode.This is where we are now with Digital, FT8 and JS8 alongside SSB and CW but Bernie is right in what he says, it's just another mode and there is room for us all on the HF spectrum. So.. go and enjoy whatever suits you, it's all Amateur Radio and we can all learn as we go.

Remember though that improving your antennas is always the most cost effective way to a better signal at the other end!

Take care, es 73, Ken G3WYN.

26/01/2021 17:25, G8JBJ John wrote:

Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
G8JBJ John
 

Thanks Ken,

I think the overall conclusion is that there's something in amateur radio for everyone, wherever you live, whatever your technical skills, however much time you have. The hobby is broad and getting broader. 

The main thing is for everyone to do something. Contribute somehow enthusiastically.

73s.

John GM8JBJ


 

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ


ᐧ


On Thu, 28 Jan 2021 at 11:34, G3WYN Ken via groups.io <G3WYN=btinternet.com@groups.io> wrote:

Nice thread John and all noted about the advantages that narrow band modes have over "ordinary" signals. Amateur radio to me is about making friends over the air and this has allowed me to, following an intitial over the air contact to have face to face meetings with other amateurs in many countries and make long term friendships lasting for many years. Sean EI7CV, Gerry, EI9DZ and Bob, N4XAT are examples of such casual meetings as are the MSARS daily and weekend nets which continue to provide further friends both at home and overseas.

Of course I used to collect cards and awards to decorate the shack but to me these are no substitute for continually talking to my friends over the air and learning more about their lives and hobbies. I remember when SSB was replacing AM more that 50  years ago and the fuss we all made about what was after all just another mode.This is where we are now with Digital, FT8 and JS8 alongside SSB and CW but Bernie is right in what he says, it's just another mode and there is room for us all on the HF spectrum. So.. go and enjoy whatever suits you, it's all Amateur Radio and we can all learn as we go.

Remember though that improving your antennas is always the most cost effective way to a better signal at the other end!

Take care, es 73, Ken G3WYN.

26/01/2021 17:25, G8JBJ John wrote:

Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
M0XYF Berni
 

I think we can all agree with that.

Carpe diem!

If we can't do something to advance the hobby given the current wave of renewed and heightened interest, then we can't really bemoan its demise if we don't. MSARS has always had an excellent record on training for example, so I think as a club we are well positioned, even if right now it's only to remain positive about the future.

Berni M0XYF


On 29/01/2021 11:35, G8JBJ John wrote:
Thanks Ken,

I think the overall conclusion is that there's something in amateur radio for everyone, wherever you live, whatever your technical skills, however much time you have. The hobby is broad and getting broader. 

The main thing is for everyone to do something. Contribute somehow enthusiastically.

73s.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ

On Thu, 28 Jan 2021 at 11:34, G3WYN Ken via groups.io <G3WYN=btinternet.com@groups.io> wrote:

Nice thread John and all noted about the advantages that narrow band modes have over "ordinary" signals. Amateur radio to me is about making friends over the air and this has allowed me to, following an intitial over the air contact to have face to face meetings with other amateurs in many countries and make long term friendships lasting for many years. Sean EI7CV, Gerry, EI9DZ and Bob, N4XAT are examples of such casual meetings as are the MSARS daily and weekend nets which continue to provide further friends both at home and overseas.

Of course I used to collect cards and awards to decorate the shack but to me these are no substitute for continually talking to my friends over the air and learning more about their lives and hobbies. I remember when SSB was replacing AM more that 50  years ago and the fuss we all made about what was after all just another mode.This is where we are now with Digital, FT8 and JS8 alongside SSB and CW but Bernie is right in what he says, it's just another mode and there is room for us all on the HF spectrum. So.. go and enjoy whatever suits you, it's all Amateur Radio and we can all learn as we go.

Remember though that improving your antennas is always the most cost effective way to a better signal at the other end!

Take care, es 73, Ken G3WYN.

26/01/2021 17:25, G8JBJ John wrote:

Spot on Phil. 

Yes, in effect there's a 30dB advantage in these ultra-narrow-band systems like FT8 and PSK. So 50W of ultra-narrow-band FT8 is equivalent to 50kW of SSB. And we'd all think that running 50kW of SSB was a bit of an overkill. A sledgehammer to crack a nut. We'd get DX even if conditions were rubbish (given 50kW both ends).

Now, here's why I thought it interesting.

I saw a tweet the other day. Someone was saying how pleased they were now that they could routinely work VK and ZL on FT8, even given the early emerging state of the ionosphere (current sunspot number is something like 30). They were rejoicing that worldwide comms would be easy at the top of the cycle. And I thought, 'where's the fun in that'. It would in that case need a rig, a computer and a pretty duff antenna. The challenge would be gone!

So do you agree? Will ultra-narrow-band degrade the challenge for self-learning offered by the hobby? And ultimately will enjoyment disappear, if it all becomes like a 99% reliability chat room exchanging '59 IO84pj'?

Now, alternatively, not everyone can have a big antenna and build or configure their own kit. So the alternative angle is that the hobby has now opened up to a huge number of folk who otherwise would not be able to participate. And in any case there are still adventures like QRP and SHF and LF. And CW - note to self!

So answer to the teaser: as a result of reduced bandwith and clever processing, ultra-narrow-band technologies have around 30dB advantage over phone.

So what does anyone think? Is FT8 great, or a hobby-killer?

Regards,

John GM8JBJ


  

John Berry

Director, TimelessTime Ltd
Mob. 07553 250 919

TimelessTime Ltd
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ
Tel: 01450 372 274
Kingfisher House, Hurstwood Grange, Haywards Heath, West Sussex, RH17 8QX
Tel. 01450 372 274
Twitter: @TimelessTimeLtd

ᐧ

On Tue, 26 Jan 2021 at 15:31, G4UDU Phil <pgodbold@...> wrote:
OOOps.      ignore the typo -  that 35 should have been 30dB


Phil G4UDU





On 26 Jan 2021, at 13:02, G8JBJ John <john.berry@...> wrote:

Hi all,

Here's a teaser for you.

Why is FT8 comms roughly the same as SSB with a power of 50kW to the antenna?

Thoughts? Then I'll tell you why I found the issue interesting.

John GM8JBJ


  

John Berry


Mob. 07553 250 919
Willowburn, Kirkton, Hawick, Scottish Borders, TD9 8QJ

ᐧ
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