Last night I tried my experimental Vertical on 300khz with a very high impedance amplifier directly at the feedpoint of the vertical. This is NOT a small whip (usual active antenna) but in my case it's a 10.5m "small whip"...
So lots of signals the amplifier needs to 'eat'...
The reason for the amplifier was mainly because I want to have the vertical really broadband from 100khz to 30Mhz ... on 20m amateur radio a full-size vertical dipole.
As the input impedance of the antenna amplifier is somewhere in 1-10MOhms for diffenrential mode AND common-mode some serious problems needed to solve:
- How to prevent common-mode noise to be amplified and interfere with "real signals".....
I had no direct answer, but just gave it a try.... so obviously there is headroom for improvement fighting the common-mode problem...
Fortunately, I am already working for a solution to get the vertical free of common-mode noise... but that will be for next night...
Ulli, ON5KQ
http://on5kq.ddns.net:8073Online web-receiver in my garden
Here are my logs with just the vertical and the amp at the feedpoint - gain is about 15-18db... (depending on frequency) - so huge signals everywhere...;-)
Count ID ref1 ref2 kHz Baud City Country Lat Lon km Deg
2 745 000 130 308,0 200 Pedra Branca (Horsburgh) Singapore 1,339 104,409 10.689 80
14 269 466 466 310,0 100 Cabo de Santa Marta Grande Lt BBrazil -28,606 -48,824 10.163 224
2 746 197 198 288,0 200 Phu Quoc Vietnam 10,018 104,018 9.909 75
3 626 652 653 310,5 200 Bachu Jiao Lt China 20,004 110,944 9.495 64
2 645 690 691 320,0 200 Nagoya Japan 35,042 136,858 9.485 36
3 614 628 629 295,0 200 Shitang China 28,267 121,617 9.387 51
4 208 228 248 292,0 100 Cooper Lt South Africa -29,937 31,009 9.349 156
38841 652 704 705 302,0 200 Ose Saki Japan 32,622 128,614 9.344 44
2 778 192 193 292,0 100 Kensington, SC United States 33,491 -79,349 6.709 288
9 844 094 095 324,0 200 Hudson Falls, NY United States 43,272 -73,542 5.621 293
55 936 332 333 319,0 200 Point Escuminac, NB Canada 47,075 -64,8 4.817 293
891 940 338 339 315,0 200 Cape Race, NL Canada 46,661 -53,075 4.058 287
4538 944 342 343 310,0 200 Cape Norman, NL Canada 51,509 -55,831 4.016 295
1158 342 484 485 308,0 200 Horta Azores 38,533 -28,617 2.814 254
2 413 626 627 289,0 100 Skagata Lt Iceland 66,121 -20,109 2.184 332
19 414 628 629 289,5 100 Raufarhofn Iceland 66,45 -15,957 2.080 336
61 540 900 901 300,0 100 Kavarna Bulgaria 43,417 28,367 2.057 102
1577 405 605 001 314,5 100 Marjaniemi Finland 65,033 24,567 2.042 29
2 513 793 823 286,5 200 Skomvaer Lt, Rost Norway 67,419 11,883 1.950 11
94 005 005 005 311,0 100 Shepelevskiy 2 Russia [Eu] 59,983 29,15 1.944 47
5 408 608 001 290,5 100 Kokkola Finland 63,833 23,167 1.903 31
13640 406 606 001 287,0 100 Klamila Finland 60,5 27,433 1.880 44
1833 531 841 001 295,5 100 Narva Estonia 59,467 28,04 1.865 48
9182 407 607 001 292,5 100 Haarajoki Finland 60,517 25,167 1.771 42
1753 462 724 001 289,0 100 Jarnas Sweden 63,486 19,655 1.753 28
21 355 510 001 303,5 100 Rota Spain 36,633 -6,383 1.712 210
2550 400 600 001 293,5 100 Porkkala Pilot Station Finland 59,981 24,403 1.705 43
3535 401 601 001 287,5 100 Mantyluoto Finland 61,599 21,475 1.675 35
12234 404 604 001 301,5 100 Turku Finland 60,442 22,224 1.630 40
22084 340 480 481 311,5 200 Cabo Carvoeiro Lt Portugal 39,365 -9,411 1.573 223
6242 530 840 840 307,0 100 Ristna Lt Estonia 58,945 22,058 1.533 45
559 464 728 728 307,5 100 Kapellskar Lt Sweden 59,719 19,087 1.442 38
3676 454 715 716 287,5 100 Torshavn Faroes 62,023 -6,841 1.425 339
18111 468 734 734 298,0 100 Nynashamn Sweden 58,946 17,958 1.338 39
2865 465 730 001 297,5 100 Hoburg Sweden 56,928 18,156 1.222 48
30 361 522 001 294,5 100 Cala Figuera Balearics 39,465 2,528 1.220 182
75 363 526 001 286,0 100 Castellon Spain 39,967 0,017 1.188 193
3672 470 738 001 288,5 100 Otterbaecken Sweden 58,867 14,1 1.171 33
7925 482 743 744 301,0 100 Rozewie Poland 54,84 18,337 1.135 59
17682 445 685 695 291,5 100 Sumburgh Shetland Isles 59,869 -1,276 1.086 347
9323 444 684 694 295,5 100 Butt of Lewis Lt Scotland 58,526 -6,27 1.083 330
43193 500 780 810 310,5 200 Faerder Lt Norway 59,034 10,533 1.067 23
12611 460 720 001 292,0 100 Holmsjoe Sweden 56,433 15,65 1.062 46
15738 469 736 001 296,5 100 Goteborg Sweden 57,617 11,967 985 32
68 351 502 001 289,0 100 Cabo Mayor Spain 43,4 -4,417 968 219
15 366 532 532 313,5 100 Cabo San Sebastian Spain 41,883 3,2 950 180
9886 451 700 701 289,5 100 Hammerodde Lt, Bornholm Denmark 55,31 14,779 950 51
6811 453 710 711 296,0 100 Skagen West Lt Denmark 57,761 10,605 949 28
4773 435 670 671 288,5 100 Tory Island Lt Ireland 55,267 -8,25 932 310
8650 503 783 813 304,0 200 Lista Lt Norway 58,116 6,572 883 13
11361 446 686 696 297,0 100 Girdle Ness Lt Scotland 57,142 -2,056 820 338
18063 001 850 851 295,0 100 Obristvi Czech Republic 50,301 14,484 805 87
11930 491 761 721 308,0 100 Gross Mohrdorf Germany 54,367 12,917 795 53
15150 443 693 001 285,5 100 Stirling [Earls Hill] Scotland 56,067 -4,067 787 325
14 336 466 466 310,0 100 Cap Ferret France 44,567 -1,25 730 208
16046 496 766 766 313,5 100 Mauken Germany 51,717 12,817 692 74
11091 495 765 765 314,5 100 Bad Abbach Germany 48,933 12,033 662 101
570 452 705 706 290,0 100 Blavandshuk Lt Denmark 55,564 8,085 660 28
12445 442 682 692 297,5 100 Point Lynas Lt Wales 53,427 -4,292 607 306
15136 441 681 691 306,0 100 Lizard Lt England 49,966 -5,202 594 268
3801 332 462 462 308,5 100 Pont de Buis France 48,3 -4,083 573 248
328 334 464 464 307,0 100 Les Sables Olonne France 46,517 -1,8 566 222
29125 492 762 001 298,5 100 Helgoland Germany 54,183 7,883 528 36
17759 493 763 001 303,5 100 Zeven Germany 53,283 9,25 527 51
17619 449 689 699 309,5 100 Nash Point Lt Wales 51,401 -3,552 480 286
18758 447 687 697 290,5 100 Flamborough Head Lt England 54,126 -0,091 465 333
10469 494 764 001 293,5 100 Iffezheim Germany 48,833 8,117 401 114
18865 439 691 001 291,0 100 Wormleighton England 52,208 -1,374 370 304
37356 428 655 656 294,0 200 Vlieland Lt Netherlands 53,3 5,067 346 22
8148 330 460 001 299,0 100 Heuville France 49,7 -1,267 323 257
15567 490 760 001 302,5 100 Koblenz Germany 50,367 7,583 316 90
16534 440 680 690 307,5 100 St Catherines Point Lt England 50,581 -1,306 313 275
38803 425 650 651 312,5 200 Hoek van Holland Netherlands 51,992 4,123 187 22
38841 426 652 653 302,0 200 Gilze Rijen Netherlands 51,617 4,933 183 43
18900 448 688 698 299,5 100 North Foreland England 51,38 1,457 157 313
Topic: DGPS Logs from Belgium - nighttime 10/11th of Februar (Read 655 times)
