Hi,
another new one on Tropical band reached > Greenland, OX3XR.
Peter, OX3XR had unfortunatelly broken the LF antennas so we had to postpone the sked for month or so. Due to very cold weather Peter was not able to come to his country QTH so it was impossible to repair all of them. We tried to make QSO from his fixed QTH but due to noisy band we did not managed QSO.
I was worried if I will hear the sigs comming from Peter so I turned my rx antenna to OX direction to be ready for our sked. After month or so I got an email that Peter repaired his antennas and he will go to the country QTH for the weekend. Unfortunatelly the weather turned again and Peter decided to not go there. So one week after Peter successfully arrived to the country QTH. After cleaning away tons of snow around the cabin and making the fire he turned ON the radio. I heard his calling CQ and although band was rather noisy we managed very nice QSO 2-way CW on 5261kHz.
Thanks to Peter, OX3XR and his willingness to spend time with repairing antennas in the hard cold weather etc. I was able to work my DXCC #16 on the Tropical band !!!
Thank You Peter and CUL on the band quite often.
73 - Petr, OK1RP
Monday, March 7, 2011
Wednesday, February 16, 2011
Sunset-watchers on 5MHz by Peter, G3PLX
Hi,
I notice several groups of 5MHz operators working each other around sunset, waiting for the skip to fade. Stations close to each other fade out first followed by those further apart. The more northerly paths will fade-out earlier that the southerly paths. It's fascinating to experience this, especially if you haven't studied it closely before. It's also quite surprising how quickly signals on a particular path can vanish.
However, I note that some people keep a close eye on the local sunset times and have grey-line maps available, and seem to be expecting that there is something 'magic' about the precise time at which the sun sets. This is all wrong.
The propagation mode in use on 5MHz around the UK at sunset is almost certainly via the F layer, which is at a height of approximately 300km. For a particular path, the relevant part of the F-layer is that which is above the midpoint of the path. If sunset has ANY significance at all in this matter, then it's going to be sunset at this point on the F-layer, not sunset on the ground.
If the sun is just setting on the ground, it will still be shining at a height of 300km, and a few quick calculations shows that the terminator (the grey-line) will be some 1800km displaced from the ground-level terminator. F-layer sunset will be more than an hour later than it is on the ground. If we were really concerned about precise sunset times, we should calculate it for the height of the ionosphere, not at sea level.
However, this isn't the whole story. At ground level we are familiar with the fact that it gets dark suddenly as the sun drops below the horizon and this visual phenomenon would still apply at the height of the F-layer. However the ionisation level doesn't drop suddenly when sunlight vanishes. Free electrons hang around for hours at this height and there's a slow decay in the critical frequency, not a sudden drop. Study of the FXi figures on the Chilton or Fairford ionosonde websites will confirm this. Indeed the critical frequency starts to drop several hours BEFORE sunset. This is simply because of the shallower angle - a given amount of solar radiation is spread over a larger area of the ionosphere as the sun moves further away from the zenith.
All of which brings me to the point of this posting. It's true to say that the sun sets later in summer and it's also true to say that 5MHz stays open later in summer, so it does make sense to run tests like this progressively later as the months go by but there is no significance in the precise timing of ground-level sunset.
73
Peter, G3PLX
I notice several groups of 5MHz operators working each other around sunset, waiting for the skip to fade. Stations close to each other fade out first followed by those further apart. The more northerly paths will fade-out earlier that the southerly paths. It's fascinating to experience this, especially if you haven't studied it closely before. It's also quite surprising how quickly signals on a particular path can vanish.
However, I note that some people keep a close eye on the local sunset times and have grey-line maps available, and seem to be expecting that there is something 'magic' about the precise time at which the sun sets. This is all wrong.
The propagation mode in use on 5MHz around the UK at sunset is almost certainly via the F layer, which is at a height of approximately 300km. For a particular path, the relevant part of the F-layer is that which is above the midpoint of the path. If sunset has ANY significance at all in this matter, then it's going to be sunset at this point on the F-layer, not sunset on the ground.
If the sun is just setting on the ground, it will still be shining at a height of 300km, and a few quick calculations shows that the terminator (the grey-line) will be some 1800km displaced from the ground-level terminator. F-layer sunset will be more than an hour later than it is on the ground. If we were really concerned about precise sunset times, we should calculate it for the height of the ionosphere, not at sea level.
However, this isn't the whole story. At ground level we are familiar with the fact that it gets dark suddenly as the sun drops below the horizon and this visual phenomenon would still apply at the height of the F-layer. However the ionisation level doesn't drop suddenly when sunlight vanishes. Free electrons hang around for hours at this height and there's a slow decay in the critical frequency, not a sudden drop. Study of the FXi figures on the Chilton or Fairford ionosonde websites will confirm this. Indeed the critical frequency starts to drop several hours BEFORE sunset. This is simply because of the shallower angle - a given amount of solar radiation is spread over a larger area of the ionosphere as the sun moves further away from the zenith.
All of which brings me to the point of this posting. It's true to say that the sun sets later in summer and it's also true to say that 5MHz stays open later in summer, so it does make sense to run tests like this progressively later as the months go by but there is no significance in the precise timing of ground-level sunset.
73
Peter, G3PLX
Friday, February 11, 2011
Texas on tropical band - US State #8
Hi all,
Unbelieving conditions - excellent score tonite.
I worked Frank, K9HMB with 58 peaking 59+ over here. His signal was so strong that I did not believed it's not hijacked callsign! Frank was for me US State #7 from Illinois. Then after I was called by Les, K4DY from NC with his nice 57! Also very strong and clear signal and we managed very nice QSO.
After I set another trial with Charles, K5SUL from TX. After almost 30mins of trials and several QSYs from QRMed channels to another one we managed correct QSO with 449 report for me and 34 report for him. Very hard job on both sides.
Interesting conditions tonite. After several calls Charles sigs fall down and I was not confident as Charles reported the same with my signal on his side in TX. We tried it again and 5mins after his sigs jumped out from the noise for very short period. Luckily at that time I hrd crystal's clean report for me. After his sigs went down under noise. As Charles reported in his email after he has to wait for the same situation in TX. My sigs were down and nil cpy. But 5-6mins after my sigs came up and Charles cpied his report correctly! In min or two my sigs again fall down to noise. It sounds like sine wave oscillating of the propagation between Czech and Texas been there with 5mins periods.
It was real challenge and big excitement for us both I gues as we tried to make QSO for more than 5 weeks nite by nite!!! Few times we almost finished it successfully but one of us did not received correct report so QSO failed... We tried SS in Texas then also SS in Czech...nil. Then - several weeks after we managed finally QSO... tonite! I gave to Charles his new one #57 and for me it was new and rare US State for WAS60. Also it is new distance record which is breaking QSO with San, K5YY from AR to my QTH I guess. (Sri San, I have to check who is winner on the web calculator...)
Really excited after hard job and I would like to thanks to Charles, K5SUL for his patience and effort to spend so much time to make just one QSO!
73 - Petr, OK1RP
Unbelieving conditions - excellent score tonite.
I worked Frank, K9HMB with 58 peaking 59+ over here. His signal was so strong that I did not believed it's not hijacked callsign! Frank was for me US State #7 from Illinois. Then after I was called by Les, K4DY from NC with his nice 57! Also very strong and clear signal and we managed very nice QSO.
After I set another trial with Charles, K5SUL from TX. After almost 30mins of trials and several QSYs from QRMed channels to another one we managed correct QSO with 449 report for me and 34 report for him. Very hard job on both sides.
Interesting conditions tonite. After several calls Charles sigs fall down and I was not confident as Charles reported the same with my signal on his side in TX. We tried it again and 5mins after his sigs jumped out from the noise for very short period. Luckily at that time I hrd crystal's clean report for me. After his sigs went down under noise. As Charles reported in his email after he has to wait for the same situation in TX. My sigs were down and nil cpy. But 5-6mins after my sigs came up and Charles cpied his report correctly! In min or two my sigs again fall down to noise. It sounds like sine wave oscillating of the propagation between Czech and Texas been there with 5mins periods.
It was real challenge and big excitement for us both I gues as we tried to make QSO for more than 5 weeks nite by nite!!! Few times we almost finished it successfully but one of us did not received correct report so QSO failed... We tried SS in Texas then also SS in Czech...nil. Then - several weeks after we managed finally QSO... tonite! I gave to Charles his new one #57 and for me it was new and rare US State for WAS60. Also it is new distance record which is breaking QSO with San, K5YY from AR to my QTH I guess. (Sri San, I have to check who is winner on the web calculator...)
Really excited after hard job and I would like to thanks to Charles, K5SUL for his patience and effort to spend so much time to make just one QSO!
73 - Petr, OK1RP
TF - DXCC #15 on 60m
Hello,
I am happy to say DXCC #15 is reached.
On 5/2/11 I worked Tor, TF3GW on 5260kHz using CW. If You are wondered what is unique on the TF on Tropical band then be awared that it is on CW... Lot of stations from TF is active on the 60m band but no CW ops unfortunatelly. Even the cross mode QSO was the problem so I really long time looked for some op who will be so nice to make QSO over there on CW.
Tor, TF3GW has setup on country QTH so it was no easy for him to go there because of lot of snow everywhere... finally he was able to come to country QTH and arrange the setup on 60m. The conditions were nice and we made QSO including some short chat.
Thank You very much Tor for Your willingness and very nice QSO. It gave me new one #15 on 60m!
73 - Petr, OK1RP
I am happy to say DXCC #15 is reached.
On 5/2/11 I worked Tor, TF3GW on 5260kHz using CW. If You are wondered what is unique on the TF on Tropical band then be awared that it is on CW... Lot of stations from TF is active on the 60m band but no CW ops unfortunatelly. Even the cross mode QSO was the problem so I really long time looked for some op who will be so nice to make QSO over there on CW.
Tor, TF3GW has setup on country QTH so it was no easy for him to go there because of lot of snow everywhere... finally he was able to come to country QTH and arrange the setup on 60m. The conditions were nice and we made QSO including some short chat.
Thank You very much Tor for Your willingness and very nice QSO. It gave me new one #15 on 60m!
73 - Petr, OK1RP
Monday, January 24, 2011
Solar flux/Sunspot index vs. QSOs logged
Hello,
as I got some emails regarding the relationship between the Solar flux, Sunspots, A-index and QSOs on LB there I am posting quick analyze from last few weeks...
as I got some emails regarding the relationship between the Solar flux, Sunspots, A-index and QSOs on LB there I am posting quick analyze from last few weeks...
All green line markers in the chart represents more than 2 QSOs on 60m band and 160m band outside EU in my log. In most cases I worked 5-6 QSOs on the low bands using 100W and my small antennas (base coil loaded half sloper for 160m w/apex 11m and inverted Z dipole w/apex 9m).
All of the good nites corresponding to a bit higher A-index and low Solar flux/Sunspot numbers in the chart.
Any comments from LB DXers are highly welcomed.
73 - Petr, OK1RP
Terrific propagation on 60m this weekend (w03)
Hello,
so I have to say unfortunatelly that after several trials during last 4 days I still did not worked Texas on Tropical band...
We arranged several skeds with Charles, K5SUL but without success. I realized that the Solar flux and Sunspot numbers were very high compare to last week so I did not expected anything special.
What was interesting this weekend on the 60m band was so directional conditions. After my calling on 5261/FA channel QSX upper channel for USA on Sat nite I got the call from Garry, K4AVC with very nice signal comes from NC. I was delighted to work him and I was a bit confident to make some another one from USA.
I spent 2 hrs on band but I did not worked anybody (few skeds failed) and even I did not received anybody on band. Also on ch5 there was no traffic.
Does anybody met this directional conditions on Tropical band also during high levels of Solar flux and Sunspot indexes?
73 - Petr, OK1RP
so I have to say unfortunatelly that after several trials during last 4 days I still did not worked Texas on Tropical band...
We arranged several skeds with Charles, K5SUL but without success. I realized that the Solar flux and Sunspot numbers were very high compare to last week so I did not expected anything special.
What was interesting this weekend on the 60m band was so directional conditions. After my calling on 5261/FA channel QSX upper channel for USA on Sat nite I got the call from Garry, K4AVC with very nice signal comes from NC. I was delighted to work him and I was a bit confident to make some another one from USA.
I spent 2 hrs on band but I did not worked anybody (few skeds failed) and even I did not received anybody on band. Also on ch5 there was no traffic.
Does anybody met this directional conditions on Tropical band also during high levels of Solar flux and Sunspot indexes?
73 - Petr, OK1RP
Saturday, January 22, 2011
US night on 60m Tropical band...
Hello,
on 19/1/2011 I listened to my communication receiver (see Tropical Band DXing by broadcast listeners article overe here on blog) and I realized that there are many stations from USA readable in between 5-6MHz broadcast band. Well it sounds like good propagation to NA tonite which maybe will alow me to work some stations on 60m ham band also. As my antenna is still not the USA killer I have to watch the conditions carefully.
I am sending an eml to few friends active on 60m and going to turn ON my K3 around 22:45z. Starting CQ on FA channel with QSX to ch2...no chance as there is huge QRM from intruder. OK > QSY to ch3 should help. No it's even worse here so I moved to finally ch5. There is no traffic and I am starting to call CQ again on FA split up to ch5.
After few minutes I am recognizing in the noise Pete, N0FW. After several trials we exchanged reports. Not easy so I guess the conditions are not the best but ok lets go to continue call on frequency.
I am getting some calls but I am not able to copy any complete call. YES...Charles, K5SUL is calling me for sure. Callsigns are completed so now we have to get report. Deep and long periods QSB making it hard. Charles did not received my report and I have nothing too. Grrrr I need the Texas on tropical band. After 30mins we are trying it again. Long minutes I am trying to send my report for him (btw sigs improved a bit). Charles completed report for him correctly. I am very nervous as some RTTY local station make me QRM for few seconds. No, not now please. We are trying to repeat the report for me but I am not able to get it correctly. After 40 minutes I scratched the battle. No correct QSO for now. :(
I hear another weak station on ch5 for me. Several trials... Again QRZ > 4? Well number 4 please again? K? recognized in the noise. I am trying all of my antennas (3pcs) but no way...Again please K4??? My correspondent must be dissapointed that I am so deaf! Grrr...again? No, no, no I am not able to copy my frend. Just K4?? but nothing more.
I call CQ again but dissapointed with preview trial I am thinking about QSY to bed.
Just about 00:55z Bob, W4DR is calling me with good sigs. Nice QSO improved my state of mind. New state for WAS60 > very good. Immediatelly after I am called by another station. Lot of noise on channel and intruder with wide spectrum of carriers making me challenge to get the call. I am asking again to call me please. Well number 4 I got but nothing more. Again...K4??? but still deep QSB and lot of noise. After several trials I am trying to use EQ in my K3. I am not experienced and situation is even worse. EQ goes OFF. Please again...K4?C. Well I got K4C?? using DSP NR and playing with Notch filter. After for some seconds signal going up. Yes I got N4CH. it should be "CH". I am sending quickly report and believing that improved signal will sustain few seconds more. OK > I am getting report and it seems that QSO is done. Ufff. I am tired.
On the ch5 calling some UK station the USA. Well but if someone is calling on ch5 it should be for me as there is split operation untill now...I am thinking and asking on FA channel CW QRZ? Yes Gary, K4AVC is calling me with solid signal. We made beautiful QSO and I am working my another US state to WAS60 > NC. Great!
Upss...I have just 3.5hrs for sleeping before my leaving to QRL (50 miles by car to Prague city) as same as 2 nites before. I am so tired and it seems that I will have problem to not sleeping close to test equipment in the lab...:(
I am turning K3 tcvr OFF and going zzzzing. In the morning my son was boggled at my face after waking up. Maybe my face was more or less zombie, hi.
When I arrived to QRL I found eml from Les, K4DY. "Petr I called You several times but finally You did not copy me." :(( I really need better antenna for rx USA I think.
Totals: 4QSOs from OH, VA and NC (4 init callsigns) using 100W and low apex Inverted Z dipole (see on this blog an article about this crazy antenna)
Nothing special just one another nite on the 60m Tropical band...
73 - Petr, OK1RP
on 19/1/2011 I listened to my communication receiver (see Tropical Band DXing by broadcast listeners article overe here on blog) and I realized that there are many stations from USA readable in between 5-6MHz broadcast band. Well it sounds like good propagation to NA tonite which maybe will alow me to work some stations on 60m ham band also. As my antenna is still not the USA killer I have to watch the conditions carefully.
I am sending an eml to few friends active on 60m and going to turn ON my K3 around 22:45z. Starting CQ on FA channel with QSX to ch2...no chance as there is huge QRM from intruder. OK > QSY to ch3 should help. No it's even worse here so I moved to finally ch5. There is no traffic and I am starting to call CQ again on FA split up to ch5.
After few minutes I am recognizing in the noise Pete, N0FW. After several trials we exchanged reports. Not easy so I guess the conditions are not the best but ok lets go to continue call on frequency.
I am getting some calls but I am not able to copy any complete call. YES...Charles, K5SUL is calling me for sure. Callsigns are completed so now we have to get report. Deep and long periods QSB making it hard. Charles did not received my report and I have nothing too. Grrrr I need the Texas on tropical band. After 30mins we are trying it again. Long minutes I am trying to send my report for him (btw sigs improved a bit). Charles completed report for him correctly. I am very nervous as some RTTY local station make me QRM for few seconds. No, not now please. We are trying to repeat the report for me but I am not able to get it correctly. After 40 minutes I scratched the battle. No correct QSO for now. :(
I hear another weak station on ch5 for me. Several trials... Again QRZ > 4? Well number 4 please again? K? recognized in the noise. I am trying all of my antennas (3pcs) but no way...Again please K4??? My correspondent must be dissapointed that I am so deaf! Grrr...again? No, no, no I am not able to copy my frend. Just K4?? but nothing more.
I call CQ again but dissapointed with preview trial I am thinking about QSY to bed.
Just about 00:55z Bob, W4DR is calling me with good sigs. Nice QSO improved my state of mind. New state for WAS60 > very good. Immediatelly after I am called by another station. Lot of noise on channel and intruder with wide spectrum of carriers making me challenge to get the call. I am asking again to call me please. Well number 4 I got but nothing more. Again...K4??? but still deep QSB and lot of noise. After several trials I am trying to use EQ in my K3. I am not experienced and situation is even worse. EQ goes OFF. Please again...K4?C. Well I got K4C?? using DSP NR and playing with Notch filter. After for some seconds signal going up. Yes I got N4CH. it should be "CH". I am sending quickly report and believing that improved signal will sustain few seconds more. OK > I am getting report and it seems that QSO is done. Ufff. I am tired.
On the ch5 calling some UK station the USA. Well but if someone is calling on ch5 it should be for me as there is split operation untill now...I am thinking and asking on FA channel CW QRZ? Yes Gary, K4AVC is calling me with solid signal. We made beautiful QSO and I am working my another US state to WAS60 > NC. Great!
Upss...I have just 3.5hrs for sleeping before my leaving to QRL (50 miles by car to Prague city) as same as 2 nites before. I am so tired and it seems that I will have problem to not sleeping close to test equipment in the lab...:(
I am turning K3 tcvr OFF and going zzzzing. In the morning my son was boggled at my face after waking up. Maybe my face was more or less zombie, hi.
When I arrived to QRL I found eml from Les, K4DY. "Petr I called You several times but finally You did not copy me." :(( I really need better antenna for rx USA I think.
Totals: 4QSOs from OH, VA and NC (4 init callsigns) using 100W and low apex Inverted Z dipole (see on this blog an article about this crazy antenna)
Nothing special just one another nite on the 60m Tropical band...
73 - Petr, OK1RP
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