1. WSJTX | Main
  2. Topics

Locked School me please

Bob
 

Naïve as I am, but when operating  in the HF bands there are two notable differences between FT4 and FT8. 1) FT8 has a handful of dB theoretical lower noise floor advantage over FT4, and 2) FT4 has an order of magnitude time advantage in being able to complete a 'QSO' in a fraction of the FT8 QSO time (I'm a 'Wham, bam, thank you Ma'am, kinda guy).

Here I am on 20M tonight, short skip is in. No thunderstorms for 800 miles. No neighbors using their 20 year old LCD TVs. No QRN. I have a dipole slung between lawn chairs. On FT8 I can decode as many as 40 stations (most disgustingly loud). On FT4, maybe 2 and occasionally three.

How/where does the 'herding instinct' factor into the preference for FT8 over FT8? There's some basic technical/philosophical/social concept that totally escapes me. I'm a virgin. School me please. Thanks, Bob.
Jim - N4ST
 

I dunno, other than FT8 has been around much longer than FT4.

Some folks just got FT4 working correctly with their log books, and electronic QSL services in the past couple of months.

 

_________

73,

Jim – N4ST

 

From: main@WSJTX.groups.io <main@WSJTX.groups.io> On Behalf Of Bob
Sent: Monday, July 13, 2020 23:37
To: main@WSJTX.groups.io
Subject: [WSJTX] School me please

 

Naïve as I am, but when operating  in the HF bands there are two notable differences between FT4 and FT8. 1) FT8 has a handful of dB theoretical lower noise floor advantage over FT4, and 2) FT4 has an order of magnitude time advantage in being able to complete a 'QSO' in a fraction of the FT8 QSO time (I'm a 'Wham, bam, thank you Ma'am, kinda guy).

Here I am on 20M tonight, short skip is in. No thunderstorms for 800 miles. No neighbors using their 20 year old LCD TVs. No QRN. I have a dipole slung between lawn chairs. On FT8 I can decode as many as 40 stations (most disgustingly loud). On FT4, maybe 2 and occasionally three.

How/where does the 'herding instinct' factor into the preference for FT8 over FT8? There's some basic technical/philosophical/social concept that totally escapes me. I'm a virgin. School me please. Thanks, Bob.

Phernell Walker <phernell@...>
 

Hi Bob,

You are 100% correct in everything.

Also, you explained the question and assumptions in basic terms, which I love.

Another factor we must consider it the clock difference DT (difference in time). This setting is critical because the other station may not hear you or vice Serra if the DT if too great. You could be transmitting and receiving during the same time interval due to the difference between their clock and yours. I use a Mac and use the internet to keep the exact universal time.

PS: I am an FT8 and FT4 addicted only HF!!!
With a Magnetic Loop I’ve logged 70 countries. Love it!!!

Hope this helps,
Phernell Walker (KC5MPS)
Portland, Oregon

Sent from the Future using
my iPhone

On Jul 13, 2020, at 8:37 PM, Bob <k4cy@...> wrote:

Naïve as I am, but when operating in the HF bands there are two notable differences between FT4 and FT8. 1) FT8 has a handful of dB theoretical lower noise floor advantage over FT4, and 2) FT4 has an order of magnitude time advantage in being able to complete a 'QSO' in a fraction of the FT8 QSO time (I'm a 'Wham, bam, thank you Ma'am, kinda guy).

Here I am on 20M tonight, short skip is in. No thunderstorms for 800 miles. No neighbors using their 20 year old LCD TVs. No QRN. I have a dipole slung between lawn chairs. On FT8 I can decode as many as 40 stations (most disgustingly loud). On FT4, maybe 2 and occasionally three.

How/where does the 'herding instinct' factor into the preference for FT8 over FT8? There's some basic technical/philosophical/social concept that totally escapes me. I'm a virgin. School me please. Thanks, Bob.
Steve marsh (M0NMA)
 

Bob 

Thanks from me for a very clear exposition of the question you wanted answering - it happens increasingly rarely now, particularly if you frequent Facebook groups.

For me, the best analogy is to compare FT4/8 to a fishing competition. If you want to catch the most fish, do you fish in the small pond with a few tiddlers in it, or the Great Lake teeming with fish?

once the ‘catch rate’ of FT4 starts to approach that of FT8 you will see a pick up in activity. At the moment I try to make a game of it by having a QSO with everyone I can see on FT4. I would never try that on FT8 unless it was one of the quieter band. 
Kevin McQuiggin (VE7ZD/KN7Q)
 

FT4 actually outperforms FT8 under high latitude disturbed ionospheric conditions, because of its wider bandwidth and larger tone spacing compared to FT8.

There is a very interesting article in the latest QEX that goes into both modes in detail.

Kevin

On Jul 13, 2020, at 20:37, Bob <k4cy@...> wrote:

Naïve as I am, but when operating in the HF bands there are two notable differences between FT4 and FT8. 1) FT8 has a handful of dB theoretical lower noise floor advantage over FT4, and 2) FT4 has an order of magnitude time advantage in being able to complete a 'QSO' in a fraction of the FT8 QSO time (I'm a 'Wham, bam, thank you Ma'am, kinda guy).

Here I am on 20M tonight, short skip is in. No thunderstorms for 800 miles. No neighbors using their 20 year old LCD TVs. No QRN. I have a dipole slung between lawn chairs. On FT8 I can decode as many as 40 stations (most disgustingly loud). On FT4, maybe 2 and occasionally three.

How/where does the 'herding instinct' factor into the preference for FT8 over FT8? There's some basic technical/philosophical/social concept that totally escapes me. I'm a virgin. School me please. Thanks, Bob.
Kenneth Blackwell
 

I have found that my contact rate is improved when fishing among a moderate density of fishers. I almost avoid 20 m on FT8 due to the density of participants. On Field Day most of my contacts were made on 15 m. Then on another occasion about 2 wks ago, I found moderated activity with FT4 on 20 and had the highest contact rate that I've ever had.

PS: I have 142 countries on mostly FT8..fishing up and down the bands from 6m to 160m. Yes, I know that there are some out there with many more. I just play at it when I feel like it. I love DX but have worked many, many stations in the USA. I spend time looking at personal information in QRZ and locating them on Google Maps. No automation for me.

Go Have Fun....work all the bands....that you can.

1 - 6 of 6