Orion splash?

[Ray Lalleu]

ORION SPLASH ?

* From Freebird, East Belgium, Sunday 7 Jan 2007 :

6280 0808 25332 Orion with a lot of calls and messages, partly 22332 through RTTY, at 0815 55544 with splatter up to 6313, John read out text message concerning his splatter, but continued *


* Reply from Orion on Monday 8 :

Hello Freebird,
thanks for the logs, much appreciated. Indeed i got a mesae about being wide and continoued. But was looking for any problems here. All settings where correct so I could not find it. *


* From Freebird, East Belgium, Sunday 14 Jan 2007 :

6265 0846 55444 Orion, Hello John, normally I enjoy your programs very much, but not with +-35khz again killing stations beside just like last weekend, over modulated, close down at 0946, thank you. I enjoy it very much to hear you next Sunday without splatter. *


* Reply from Orion on Monday 15 :

Hello Freebird,
Thanks for the logs. After lost weekend Of course I did some tests. Last Sunday was on air with some mesure stuff, and didn't see anything wrong.
Of course I'm sorry it's not my plan to splatter.
Overmodulation was not visible on the scoop. onec again, I'm sorry *


Almost no other one complains about an Orion splash. Maybe the sound is a bit on the bright side, and next frequencies are hard to listen to. But look carefully the following lines :


* From Goran, S.Sweden, Sunday 14 Jan 2007 :

The 13th and 14th I had the pleasure to visit the QTH of Malmoe Shortwaveclub, in Saxtorp, where they have some nice antennas. I used an 700 meter long in direction Central Americas/North South America.
It was some years since I had the oppurtunity to do this kind of DX, otherwise just an dipole.
After this DX-camp I must say that a good working dipole for the 48 m band is almost as good as a long antenna for the 48 m band,
[...]
6265 07.57 Orion Radio, always bright and early, with a killer signal today. Unfortunatly it was quite heavy splatter here. Could start to hear his signal on 6274. SINPO 55555. Could be a local station! *


* Orion replies :

Hello Goran,
Thanks for the logs much appreciated, well perhaps I was close to you?
Still don't know what's wrong no other told me I was that wide and didn't change anything! *


* Then Goran adds :

Well Orion, your signal was very impressive and I think maybe the very long antenna had something to do with your signal beeing wide, I haven't heard that before at my regular QTH. Could it be that way, any ideas anyone? *

* END OF QUOTES *

I think I have the idea... Goran with the 700m long antenna was receiving a very very strong signal from Orion. Freebird doesn't need a long antenna to get a very very strong signal from Orion : his place is in the "best" lobe from Orion.

The problem is some form of overloading the receiver, also check the antenna contacts, just to be sure, but I suggest trying antenna attenuation. I think there is not only overloading, but also reciprocal mixing (from a less than ideal local oscillator using PLL), so I suggest also trying other receivers, maybe a more recent one, but I think it's cheaper first to check with an older one, a fully analog receiver (that has a cleaner local oscillator).

Maybe this makes you mind... So:
1) Think, the very very strong signal is just outside the main passband filter, and the AGC is fully open, looking for weak signals.
2) Maybe you think of broadcasters with hundreds of kilowatts : but those broadcasters are not wasting their kilowatts on short range paths, most of the power is sent at lower site angles just to reach longer distances. They are not warming the ionosphere just above the antenna (as do the typical -low- pirate transmitting antenna).

So what else can be done?

Transmitting :
1) Orion should raise the dipole antenna up to a half wavelength high (yes that is 24 meters high!) so most of the power would be sent to listeners 500 to 2000 km away.
2) Or Orion could use a vertical quarter wavelength antenna (with many radials in the ground) to reach listeners 1000 to 3000 km away (but then the neighbours could also hear Orion in every phone, so this should be used only in the country with no neighbours)
3) Large loops do not need high masts nor earth radials. See chapter 10 in "Low band DXing" from John Devoldere ON4NU (shows models for 80m amateur band, to scale down). A few ones (see figures 10-3, 10-10, 10-11, 10-18, 10-24) do not waste power at high angles, but are vertically polarized (maybe not quite good for RFI in neighbours homes).
4) A 2 wavelenths horizontal loop (a few meters high) should do the best (but that means a square 24m on each side, no close neighbours!)
5) While waiting for a better suited antenna, Orion should use lower power when the sky is open for short distances

Receiving :
6) Listeners should be aware that the first generation of low cost PLL receivers (in the 1980's) was often flawed, with noisy local oscillators. The output of those old PLL oscillators have sidebands, and those sidebands are mixing with strong signals outside of the intended receiving channel.
7) Listeners could try tuned SW loops : sharp tuned peak and maybe still some form of directivity (not too much on 48m for sky waves, but very useful against local RFI).

Hope this helps. Try, because I can't say better.
(Maybe the complainers could add something about their receivers and antennas).

Ray

[Goran]

Hello Ray!

First up, I didn't complain about the ORion splashing, it was just to let him now, to maybe correct the problem if there where any.

Second I use an Kenwood R-5000 receiver and at the time I heard Orion I used an 700 meters longwire in direction south.

I aslo agree that this long antenna may be the problem and the reason why I had such a heavy splash from him.

Regards
Göran

[JoJo]

Hello Guys,

thanks for all the replay, much appreciated! Indeed splatter or being wide is a problem. I read all above of course and did many antenna tests! raising up the inverted V is not posible. As I have many neigbours here. The vertical is an option but works fine on 32 meters and higher.

Indeed it could also at the receiver side and of course conditions, we have some strange conditions the last time. As the signal was big at some receivers that could be the reason.

About the audio setup, Only had some problems with the mixer, sometimes it rais up the volume but this would be eliminated by the lim. comp. I also use a low and high pass filter and cuts all above 6kc.

For sure I will do the sunday morning px in 52 meters, 5725kc It's almost the same as 48 meterband and it's vy quiet here, no other pirates. If the signal is width or if I am splattering this would be no problem.

About the power; In the beginning I used 100watt, and raised up to 750watt for a short time. Later 400watt, now I use 350watt
Because the strange conditions and early time I don't think using 100watt would be fine to reach my frinds in the east of germany and Cze?

after all I don't see this as complaining so it's no problem for me, please keep your ears open and let me know.

One remark form my side, If I got a mesage about being wide or splashing first thing is looking at all above if all is ok, this can only be done with the tx on, So I don't switch of the tx. Mostly I closedown at 0900utc


thanks,

john

[Ray Lalleu]

You've found a solution for some time (while nobody else move to the same range).
I think to an other frequency (so long as you close down early) : 6240 kHz, occupied later by JRRI/BRI. And "splash" around at that time could be acceptable, maybe?

Well, think to the other antennas (not higher than an inverted V) to send most of your power at lower site angles / longer ranges. You would have more numerous happy listeners, close listeners as well a s far away listeners.

Hope everyone happy in this hobby.

[JoJo]

Thanks again for all replay,

Well abou the antenna's; I've tested some like vertical, slopers, loops but I don't have the space here, and the 1/2 wave inverted V ( with balunand currend) works best for me and my neighbours and that's th emot important for me because I have to live with them.

Best would be sitting all alone on a mountain, but we don't have that hi.
Just keep on testing, With all stuff like audio and antenna's.
I guess It is also the point form the strange conditions, because I use this setup for a year now and this is the first time we are talking about splass now. Any way thanks again for all info and enjoy your hobby.

john

[Bycross Radio]

I wondered why I didn't hear you last weekend. I didn't tune down far enough! Is this new freq likly to become a regular one?

[JoJo]

Hello Bycross radio,

Indeed this is the new freq. for some time, but sure will be back on 48 meters.