[digitalradio] Best line of the day

2008-04-13 Thread Andrew O'Brien
Copied on 40M  PSK today

 I am having a hard time copying even though your signal is 599 , not
decoding every thing.

Andy K3UK



Re: [digitalradio] Best line of the day

2008-04-13 Thread Dave 'Doc' Corio
Right up there with ur 599 599 pse rpt name es qth

73
Dave
KB3MOW


Andrew O'Brien wrote:

 Copied on 40M PSK today

  I am having a hard time copying even though your signal is 599 , not
 decoding every thing.

 Andy K3UK

 
 

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Re: [digitalradio] Best line of the day

2008-04-13 Thread Tim N9PUZ
Any fool can know, the point is to understand. (Albert Einstein)

Tim, N9PUZ


Andrew O'Brien wrote:
 Copied on 40M  PSK today
 
  I am having a hard time copying even though your signal is 599 , not
 decoding every thing.
 
 Andy K3UK



Re: [digitalradio] Best line of the day

2008-04-13 Thread Jose A. Amador

I agree. Static crashes are a powerful QRN source here too.

Guess Olivia would be better, even 8/250 would stand a better chance of 
good copy.

In spite of strong signals, if there is no second chance, it does not 
matter much how clever Varicode is. It is certainly a big step ahead on 
quiet bands, but when QRM dominates, it is simply not enough.

73,

Jose, CO2JA

David Little wrote:

 That's what happens when there are static crashes, like those from the 
 string of cells (or super-cells) moving  across the Eastern US. 
  
 Got FEC??
  
 The station could improve the odds against him by using faster (or no 
 AGC)  for quicker recovery time to lessen the lost data (again, no FEC - 
 no redundancy- no second chances)...
  
 Of course, the ease of using PSK as opposed to a mode with error 
 correction attracts the masses, and is is narrow bandwidth...
  
 The station probably was actually decoding everything, including the 
 static crashes and resulting lost data
  
 David
 KD4NUE
  
 
 -Original Message-
 *From:* digitalradio@yahoogroups.com
 [mailto:[EMAIL PROTECTED] *On Behalf Of *Andrew O'Brien
 *Sent:* Sunday, April 13, 2008 8:17 AM
 *To:* digitalradio@yahoogroups.com
 *Subject:* [digitalradio] Best line of the day
 
 Copied on 40M PSK today
 
  I am having a hard time copying even though your signal is 599 , not
 decoding everything.
 
 Andy K3UK
 



Re: [digitalradio] Best line of the day

2008-04-13 Thread kh6ty
I agree. Static crashes are a powerful QRN source here too.

Guess Olivia would be better, even 8/250 would stand a better chance of 
good copy.

In spite of strong signals, if there is no second chance, it does not 
matter much how clever Varicode is. It is certainly a big step ahead on 
quiet bands, but when QRM dominates, it is simply not enough.

73,

Jose, CO2JA


Hi Jose,

We are using PSK63 to PSK250 on 2 meters for NBEMS with excellent success and 
fast data transfers, as there is essentially no problem with static crashes on 
2 meters. Wether we use PSK63, PSK125, or PSK250 is simply a function of the 
path loss on 2 meters we have to overcome to get a usable S/N, and there is no 
QSB to contend with either (up to about 100 miles).

However, as you note, static crashes are a big problem for PSK31, and a huge 
problem for PSK250, so those testing NBEMS on HF have had to resort to MFSK16 
(already included in the NBEMS software), which is much less disturbed by 
static crashes. However, data transfer is very slow using MFSK16, especially 
after adding ARQ, so we are seriously considering using DominoEx, which is 
faster, easier to tune, within 1.5 dB of the weak signal performance of MFSK16, 
and that we hope is more like MFSK16 in tolerance to static crashes, but we do 
not have enough experience to know if it is or not.

The problem is that DominoEx is not used a lot, so if you, and others reading 
this post, can compare DominoEx11, or DominoEx16, to MFSK16 during times of 
many static crashes and let us know the result, I would greatly appreciate it. 

Multipsk supports both DominoEx, and MFSK16 under Windows, as does fldigi, 
under Linux.

73, Skip KH6TY
NBEMS Development Team