Recording the contest

Recording contests is a great tool to detect problems and improve operating eficiency
There is a lot of interest in the way an operator can make use of SO2R, particualrly at high rates. In the examples below there are some interesting examples of CT1BOH operating in differente situations.

You should listen to these files with headphones to fully appreciate the radio 1, radio 2 differences.
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EA8ZS SO2R

2 minute file from 12:50 to 12:52z
EA8ZS SO2R. Radio 1 runing on 15 meters, radio 2 looking for mults on 10

12:50:01   begin file
12:50:03  15  OH2KM
12:50:23  15  PA3AAV
12:51:04  10 TO4A
12:51:16  15  OK1AJR
12:51:29  15  DL8HCO
12:51:44  15  US7IM
12:51:59   end of file
In this file you can hear exactly what I was hearing during 2004 CQWW CW. You never listen to EA8ZS signal, because while I am transmiting I always listening to radio 2. During this 2 minute file 6 stations were worked. One multiplier was spotted and worked. Note there is no interference on 10 while I transmit on 15 - perfect situation for efficient SO2R operation.
Of special interest here is it took me a couple of calls to get trough TO4A pile-up. DL8HCO called and was heard. The decision not to work him right away did not proove correct because I could not break TO4A pile-up in my first call. But he called a bit later anyway. This is almost always the case when you are a DX station, but I should have worked one station after PA3AAV while wainting to call TO4A again, even tough there was no pile-up on my end.

EA8ZS High Rate

EA8ZS1 minute file from 03:27z to 03:28z.
EA8ZS SO2R. Radio 1 running on 40 meters, radio 2 looking for mults on 20.

3:26:59  begin of file
3:27:00  40  W6YI
3:27:07  40  N3AM
3:27:15  40  W5GN
3:27:22  40  K8JQ
3:27:33  40  KY7M
3:27:42  40  NR0X
3:27:51  40  KI7Y
3:28:00  end of file
7 stations are worked in this minute at a 420 QSO/Hour rate.
Perfect pile-up, only one or two stations calling at the same time.
You can also listen to radio 2 on 20. I cannot hear very well on 20 due to 40 meter signal interfering on the second radio but still some signals come through. A litle bit before at 03:21Z (and not in this file) HC8N was worked on 20. They were loud and I could listen to them over my own 40 meter interference. 40 meters was the best band from EA8ZS, but because of interference litlle SO2R could be done on 20/15/10 while transmitting on 40. On 80 and 160 terrible noise prevented further SO2R there.
Of special interest EA8ZS signs his call once during this minute. Because of that the elapsed time between K8JQ and KY7M is not around 7 seconds but 11 seconds.

P40E SO2R High Rate

7 minute file from 01:34:28 to 01:41:31
P40E SO2R. Radio 1 on 40 meters, radio 2 looking for mults on 10.

1:34:28  begin of file
1:34:28  40  K4IE
1:34:40  40  W1ZS
1:35:10  10  ZL6QH
1:35:26  40  EA4KA
1:35:37  40  DL2TG
1:35:56  40  WB2FUE
1:36:07  40  VE3NZ
1:36:24  40  K5WAF
1:36:35  40  YT7AA
1:36:34  40  DF6MU
1:37:17  40  F5NGA
1:37:27  40  OZ1CBW
1:37:41  10  LQ7D
1:37:52  40  EA6IB
1:38:03  40  K5IID
1:38:23  40  RD3R
1:38:41  40  NZ5A
1:39:01  40  W1HR
1:39:19  40  RV6LN
1:39:44  40  IK4UNH
1:39:56  40  OH4R
1:40:09  10  HC8N
1:40:18  40  K4FPF
1:40:32  40  S56A
1:40:56  40  VE3EJ
1:41:06  40  DJ5MW
1:41:15  40  K3ONW
1:41:25  40  K1ZZ
1:41:31  40 end of file
28 stations are worked in this 7 minute file at a 240 QSO/hour rate.
3 multipliers (ZL6QH, LQ7D, HC8N) are worked.
If you think SO2R in the middle of a high rate situation is not possible, please do change your mindset now.
In this file you can hear my own interference from 40 into 10 meters but it is not too bad, I can still hear the band OK. When I transmit on 10 there is no interference into 40 tough, as it would be expected.
Of special interest I would like to mention that I did work LQ7D. Argentina is not really a difficult multiplier and I was sure I would be called by another LU later on, but I worked him for two reasons: first there was a medium probability he would not call me in the contest so I decided to call him instead of working another station in the 40 meter pile-up, second it did not affect my 4 a minute rate at all, so we can say I gained a QSO out of this situation - the pile-up will call me this guy probably not, and just in case the LU multiplier was in the bag. Also notice how easy it is to scan the 10 meters band during the night. No narrow filter needed and almost every signal on the band comes from south and from Aruba that means multipliers. The use of  SO2R to scan a crowded band during the day, full of junk (i.e. non multipliers station) is a bit different and a lot more challeging than what you are hearing here tough.

CT1BOH - Josť Carlos Cardoso Nunes - ct1boh@gmail.com