Hi Take,
On 7/3/2018 8:03 PM, Tsutsumi Takehiko JA5AEA wrote:
Joe, Just “listened and watched the show“???
I saw a critical message last night on a Japanese SNS that KH1/KH7Z FT8
OP should pay their respect to K1JT repeated calls and must promptly
return RR73.
Never fear, I have worked KH1/KH7Z on 20 and 30m already. I hope still
to catch them on 40m. :-)
This is just my back-of-the envelope calculation, but the link-budget
improvement can be 15dB, not 7dB at Nslots=5
Additional gain comes from:
1. Adopt QRA64 or QRA128 utilizing 3kHz wide fox TX bandwidth : +4dB gain
2. 65% packed message length base on Bill’s suggestion : +4dB gain
Then, the figure becomes -14 + 7 + 4 + 4 = +1.
Of course I encourage you to design and implement a protocol that will
achieve this sensitivity improvement!
However: I do not accept either of the +4 dB numbers you have given.
Steve has already pointed out part of the problem. You give no details
of where you think you can gain another +4 dB from changes in "packed
message length". I do not think that's achievable, either, while still
conveying everything (1 Fox callsign, 5 Hound calls with RR73, another 5
Hounds with a report) in a single message.
-- 73, Joe, K1JT
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
wsjt-devel mailing list
wsjt-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/wsjt-devel
