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1
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от R7NT 21 Апрель 2019, 21:12:27 »
Apr 20-21  Best QRB/reports WSPR15 / WSPR2 / OP32 / OPds :
2019-04-21 06:20     WH2XXP     0.137507     -29     0     DM33nn     5     EB8ARZ/2     IL18uk     8859     63 (1)
2019-04-21 06:20     WH2XND     0.137527     -27     0     DM33xt     20     EB8ARZ/2     IL18uk     8778     63 (4)
2019-04-21 12:40     JH1OFX     0.137583     -26     0     PM95ql     0.5     KL7L     BP51ip     5628     36 (1)
2019-04-21 11:36     JA1NQI     0.137485     -26     0     QM05dv     0.1     KL7L     BP51ip     5542     36 (10)
2019-04-21 10:08     WH2XXP     0.137507     -11     0     DM33nn     5     KL7L     BP51ip     4047     332 (78)
2019-04-21 07:08     WH2XND     0.137527     -8     0     DM33xt     20     KL7L     BP51ip     4059     331 (92)
2019-04-21 04:04     WH2XXP     0.137507     -25     0     DM33nn     5     VE3HOA     FN15xg     3385     56 (7)
2019-04-21 05:52     WH2XXP     0.137507     -23     0     DM33nn     5     WA3U     FM29co     3354     68 (69)
2019-04-21 04:52     WH2XXP     0.137506     -29     0     DM33nn     5     N2HQI     FN13sa     3318     61 (2)
2019-04-21 02:56     WH2XXP     0.137504     -25     0     DM33nn     5     N3FL     FM19ua     3312     69 (28)
2019-04-21 03:48     WH2XND     0.137527     -20     0     DM33xt     20     VE3HOA     FN15xg     3306     57 (33)
2019-04-21 09:20     WH2XXP     0.137511     -17     0     DM33nn     5     K3MF     FM19sr     3297     67 (90)
2019-04-21 03:40     WH2XND     0.137527     -16     0     DM33xt     20     WA3U     FM29co     3272     68 (109)
2019-04-21 07:24     WH2XND     0.137527     -23     0     DM33xt     20     N2HQI     FN13sa     3237     61 (26)
2019-04-21 07:20     WH2XXP     0.137507     -17     0     DM33nn     5     KD2OM     FN12gx     3236     61 (123)
2019-04-21 03:04     WH2XND     0.137524     -19     0     DM33xt     20     N3FL     FM19ua     3230     69 (60)
2019-04-21 07:08     WH2XXP     0.137507     -33     0     DM33nn     5     WA2ZKD     FN13ed     3225     60 (1)
2019-04-21 07:52     WH2XND     0.137527     -29     0     DM33xt     20     WA2ZKD     FN13ed     3145     61 (14)
2019-04-21 03:24     WH2XND     0.137530     -9     0     DM33xt     20     K3MF     FM19sr     3215     68 (104)
2019-04-21 07:20     WH2XND     0.137527     -15     0     DM33xt     20     KD2OM     FN12gx     3156     61 (139)
2019-04-21 08:32     WH2XXP     0.137508     -16     0     DM33nn     5     NO3M     EN91wr     3002     63 (54)
2019-04-21 04:24     WH2XXP     0.137507     -20     0     DM33nn     5     WA3TTS     EN90xn     2996     65 (114)
2019-04-21 10:24     WH2XND     0.137528     -10     0     DM33xt     20     NO3M     EN91wr     2921     63 (60)
2019-04-21 03:20     WH2XND     0.137527     -14     0     DM33xt     20     WA3TTS     EN90xn     2915     66 (127)
2019-04-21 03:12     WH2XXP     0.137507     -23     0     DM33nn     5     N8TL     EN81db     2696     63 (5)
2019-04-21 07:20     WH2XXP     0.137507     -19     0     DM33nn     5     WV5L     EM74sc     2617     81 (71)
2019-04-21 03:28     WH2XND     0.137527     -25     0     DM33xt     20     N8TL     EN81db     2615     64 (5)
2019-04-21 06:56     WH2XND     0.137527     -17     0     DM33xt     20     WV5L     EM74sc     2536     81 (100)
2019-04-21 10:28     WH2XXP     0.137507     -21     0     DM33nn     5     W4ATV     EM64or     2397     80 (86)
2019-04-21 10:36     WH2XXP     0.137508     -9     0     DM33nn     5     WA9CGZ     EN61ch     2366     61 (106)
2019-04-21 10:44     WH2XXP     0.137507     -16     0     DM33nn     5     N8OOU     EM68es     2331     68 (99)
2019-04-21 03:52     WH2XND     0.137527     -18     0     DM33xt     20     W4ATV     EM64or     2316     80 (116)
2019-04-21 01:34     R7NT     0.137540     -27     0     KN97lf     200     DL1GCD/1     JN48ar     2291     286 (3)
2019-04-21 09:52     WH2XND     0.137528     -4     0     DM33xt     20     WA9CGZ     EN61ch     2285     62 (144)
2019-04-21 06:08     WH2XXP     0.137507     -20     0     DM33nn     5     VE6JYKIWI     DO33os     2247     0 (55)
2019-04-21 07:20     WH2XND     0.137527     -13     0     DM33xt     20     N8OOU     EM68es     2249     69 (138)

2019-04-21 00:45     R7NT     0.137602     -27     0     KN97lf     200     DK7FC/15     JN49ik     2234     288 (6)
2019-04-21 06:20     WH2XND     0.137527     -15     0     DM33xt     20     VE6JYKIWI     DO33os     2220     359 (83)
2019-04-21 00:45     R7NT     0.137602     -25     0     KN97lf     200     SM2DJK     KP03au     2180     335 (5)
2019-04-20 19:40     R7NT     0.137540     -28     0     KN97lf     200     SM2DJK     KP03au     2180     335 (1)
01:33    136 R7NT de SM2DJK Op32 2178 km -32 dB F:1% in Umea 1541,0 Hz with 200w + E.sLoop (6)
2019-04-20 19:33 R7NT    2060km 137541.000Hz   8mHz -28.7dBOp  97% 21.9dB DF6NM (10)
20:10    136 UT7GH de SM2DJK Op32 Deep Search 2059 km -45 dB in Umea 1507,0 Hz (1)
2019-04-20 20:36     R7NT     0.137540     -21     0     KN97lf     200     DL0AO/2     JN59vk     2012     287 (14)
2019-04-21 02:33 R7NT    2012km 137540.999Hz   4mHz -27.8dBOp 100% 20.7dB DL0AO (12)
2019-04-21 09:00     K3MF     0.137402     -19     0     FM19sr     1     SWLK5     EM13     1959     256 (23)
2019-04-20 20:38     R7NT     0.137540     -27     0     KN97lf     200     SV8CS     KM07jr     1819     241 (4)
02:33    136 R7NT de SV8CS-1 Op32 1818 km -30 dB F:20% in Zante  Isl. 2nd QTH 1540,8 Hz with 200w + E.sLoop (10)
2019-04-21 01:45     R7NT     0.137602     -32     0     KN97lf     200     SV8RV     KM07ks     1811     241 (6)
2019-04-21 01:45     R7NT     0.137602     -32     0     KN97lf     200     SV8RV-1     KM07ks     1811     241 (6)
2019-04-21 02:33 R7NT    1811km 137540.856Hz   5mHz -39.1dBOp  96% 20.3dB SV8RV (9)
02:33    136 R7NT de SV8RV Op32 1809 km -34 dB F:3% in Zakynthos(Zante) isl. GREECE 1540,8 Hz with 200w + E.sLoop (8 )
2019-04-21 01:38     R7NT     0.137539     -19     0     KN97lf     200     OE3EMC     JN78jo     1800     284 (6)
2019-04-21 01:34     OE3EMC     0.137421     -19     1     JN78jo     0.02     SM2DJK     KP03au     1725     9 (38)
2019-04-20 09:58     VK5FQ     0.137534     -17     0     PF95gc     1     VK4RBC     QG62lw     1624     62 (3)
2019-04-20 19:12 UT7GH   1622km 137506.965Hz   5mHz -36.5dBOp  98% 20.4dB DF6NM (3)
2019-04-20 09:46     VK4YB     0.137597     -19     0     QG62ku     5     VK5FQ     PF95gc     1612     234 (4)
2019-04-21 01:38     DC0DX     0.137428     -16     0     JO31lk     0.1     SM2DJK     KP03au     1578     24 (17)

2019-04-20 20:10 UT7GH   1574km 137506.960Hz   2mHz -33.2dBOp  84% 18.3dB DL0AO (4)
2019-04-21 02:20     OE3EMC     0.137421     -24     1     JN78jo     0.02     SM3LNM     JP82qg     1528     5 (13)
2019-04-21 11:20     WH2XXP     0.137507     +2     0     DM33nn     5     SWLK5     EM13     1466     86 (128)

2019-04-21 01:45     R7NT     0.137602     -26     0     KN97lf     200     SP5XSB     KO02ld     1401     300 (6)
01:33    136 R7NT de SP5XSB Op32 1400 km -29 dB F:5% in Raszyn nr Warsaw (6)
19:12    136 UT7GH de SV8CS-1 Op32 1390 km -36 dB F:1% in Zante  Isl. 2nd QTH 1506,9 Hz with 1w + LW (2)
2019-04-21 11:16     WH2XND     0.137527     +5     0     DM33xt     20     SWLK5     EM13     1388     87 (132)
2019-04-20 14:50     VK3DQL     0.137473     -28     -1     QF22ik     50     VK4YB     QG62ku     1388     36 (2)
2019-04-20 19:00     VK4RBC     0.137452     -19     1     QG62lw     1     VK3DQL     QF22     1384     211 (29)

2019-04-20 20:10 UT7GH   1379km 137506.822Hz   3mHz -44.2dBOp 100% 15.9dB SV8RV (3)
2019-04-20 09:38     VK4YB     0.137597     -27     0     QG62ku     5     VK3DB     QF31dt     1373     205 (3)
2019-04-20 09:30     VK4YB     0.137602     -7     -1     QG62ku     5     VK3DQL     QF22     1371     211 (38)
2019-04-20 09:46     VK4YB     0.137597     -27     0     QG62ku     5     VK3LM     QF31fs     1370     204 (5)
2019-04-21 02:28     OE3EMC     0.137421     -29     1     JN78jo     0.02     G0LUJ     IO83ls     1364     302 (2)
2019-04-21 02:38     DC0DX     0.137428     -16     0     JO31lk     0.1     SM3LNM     JP82qg     1357     23 (16)
2019-04-21 08:42     WA9CGZ     0.137422     -28     0     EN61ch     0.5     SWLK5     EM13     1193     226 (13)
2019-04-20 10:02     VK5FQ     0.137539     -30     0     PF95gc     1     EJTSWL     QE37pd     1163     142 (1)

2019-04-21 00:33 R7NT    1152km 137541.040Hz   2mHz -36.5dBOp  87% 18.5dB EW6X (6)
18:33    136 R7NT de EW6X Op32 -37 dB F:43% in KO45kl (1151 km) Polotsk + miniwhip 137541.1 Hz (6)
2019-04-21 02:40     WH2XND     0.137527     -7     0     DM33xt     20     WB7ABP     CM88ok     1093     301 (24)
2019-04-21 06:48     WH2XND     0.137526     -2     0     DM33xt     20     KPH     CM88mc     1091     299 (214)
2019-04-21 11:08     WH2XND     0.137527     -9     0     DM33xt     20     KJ6MKI     CM88oi     1089     301 (167)
2019-04-21 07:00     WH2XND     0.137527     -16     0     DM33xt     20     W6SFH     CM88pl     1088     302 (126)
2019-04-21 11:32     WH2XND     0.137527     -24     0     DM33xt     20     WW6D     CM88pk     1086     301 (19)
2019-04-20 23:54     DC0DX     0.137427     -26     0     JO31lk     0.1     IZ6BYY     JN62wv     1083     149 (3)
2019-04-21 08:52     K3MF     0.137402     -22     0     FM19sr     1     W4ATV     EM64or     1069     242 (34)
2019-04-20 23:56     WH2XXP     0.137507     -18     0     DM33nn     5     KK6EEW     CM88on     1050     305 (18)

2019-04-20 23:33 R7NT    1045km 137540.994Hz   3mHz -31.6dBOp 100% 21.8dB YO/4X1RF (14)
2019-04-21 02:44     WH2XXP     0.137507     -13     0     DM33nn     5     WB7ABP     CM88ok     1043     304 (21)
2019-04-21 06:48     WH2XXP     0.137506     -7     0     DM33nn     5     KPH     CM88mc     1039     302 (247)
2019-04-21 06:48     WH2XXP     0.137507     -17     0     DM33nn     5     KJ6MKI     CM88oi     1039     304 (127)
2019-04-20 09:18     VK5FQ     0.137539     -26     0     PF95gc     1     VK5AZL/2     QF49eb     1017     67 (3)

2019-04-20 19:12 UT7GH   1016km 137507.001Hz   3mHz -34.3dBOp  88% 19.6dB EW6X (1)
19:12    136 UT7GH de EW6X Op32 -36 dB F:3% in KO45kl (1016 km) Polotsk + miniwhip 137507.0 Hz (2)
2019-04-21 05:40     R7NT     0.137540     -28     0     KN97lf     200     RN3AUS     KO85fn     943     350 (1)
2019-04-21 05:33 R7NT     943km 137541.007Hz  10mHz -36.6dBOp  92% 21.6dB RN3AUS (7)
06:33    136 R7NT de RN3AUS Op32 -33 dB F:43% in KO85fn (942 km) nr Moscow + MiniWhip 137540.0 Hz (4)
2019-04-20 19:12 UT7GH    566km 137506.957Hz   5mHz -38.6dBOp 100% 18.7dB YO/4X1RF (4)

2019-04-21 05:45     R7NT     0.137602     -16     0     KN97lf     200     UT7GH     KN66hq     484     265 (1)
2019-04-21 05:34     R7NT     0.137540     -18     0     KN97lf     200     UT7GH     KN66hq     484     265 (3)
05:33    136 R7NT de UT7GH Op32 484 km -20 dB F:13% in Kherson 1541.0 Hz with 200w + E.sLoop (2)
12:55    136 JH1OFX de JA5FP Op32 72 km +0 dB F:3%_End in Yotsukaido, Chiba 1497.3 Hz with 20w + 17mH Vertical + 40m Long Top
12:55    136 JH1OFX de 7L1RLL Op32 18 km +7 dB F:1%_End in Kanagawa, JP 1498.0 Hz with 20w + 17mH Vertical + 40m Long Top Loa
WSPR15: TX-1 RX-5
WSPR2 >1000km : TX-13 RX-40
OP32 : TX-3  RX-9 OPds RX-6
(n) - общее кол-во спотов от корреспондента - показан самый лучший - при одинаковых уровнях, выбран самый первый по времени
2
A quartz piezoelectric crystal converts electrical energy to mechanical energy and vice versa.

It won't convert electrical energy into an electromagnetic wave by itself.

Magnetostrictive material such as Terfenol-D will convert mechanical vibrations into a fluctuating magnetic field.

This can generate an electromagnetic wave directly using the homopolar effect.

A piezoelectric transducer can be used to mechanically drive magnetostrictive material to produce an EM wave.

Efficiency is several orders of magnitude greater than a wire antenna enabling practical portable VLF transmitters.

73 de VA3VVV
3
Am 19.04.2019 um 17:28 schrieb Clemens Paul:

    РазвернутьРазвернуть

Hi Clemens and group,

here is the promised extension of my tests, for better comparability merged with the first results (my post on the reflector from 20190418):

Having no VLF quartz yet, I made some preliminary tests with a randomly available HC-6-U quartz, QRG 2434 kHz, wavelength 123 m.

    TX: Sythesizer Schomandl MG100M, 300 Hz ... 100 MHz, smallest step 0.1 Hz, Ri = 50 Ohms, P = 10 dBm, output tied to first leg of quartz, alternatively direct to the antenna wire
    RX: Perseus SDR with an active rod antenna on my garage, fed by a solar system, no external wire connections, air-line distance 100 m to my shack
    Antena wire: 2 m or 4 m, laid out in the shack, tied to second leg of quartz, alternatively direct to the TX output
    alternatively antenna wire only resonated by two roller plus one fixed inductors in series, fed directly from the TX output

Results with 2 m antenna wire:

    with quartz resonator: fres = 2,433,908.8 Hz, RX level at resonance = - 63,1 dBm, - 3dB-bandwidth = 48.3 Hz resulting in Q = 50391
    without quartz resonator: RX level = - 85,4 dBm resulting in a gain of 22.3 dB with quartz
    comparision: my 13 m T-Marconi with top load 4 x 33 m, tuned to 2434 kHz and fed by the synthesizer with 10 dBm results in a RX level of - 32.1 dBm ;-)
    with inductive tuning at 2,434,000 Hz: RX level = - 60.1 dBm resulting in a gain of 3dB compared with quartz. -3 dB-bandwidth = 249 kHz resulting in a loaded Q = 9.8

Results with 4 m antenna wire:

    with Quartz resonator: fres = 2,433,773.6 Hz, RX level at resonance = - 59 dBm. - 3 dB-bandwidth = 49.4 Hz resulting in Q = 49376
    without quartz resonator: RX level = - 75.4 dBm resulting in a gain of 16.4 dB with quartz
    with indctive tuning at 2,234,000 Hz: RX level = - 57.3 dBm resulting in a gain of 1.7 dB compared with quarz. - 3 dB-Bandwidth = 390 kHz resulting in a loaded Q = 6.2

With all tests there was no additional resistive matching at the TX output. The tests at resonance showed the usual unbalance between lower and upper - 3 dB-points. With L-tuning the upper is further away from the resonance frequency than the lower. With quartz-tuning this effect is contrawise and of course absolutely much lesser accented. At a first glance L-tuning offers advantages due to its comparable huge bandwidth and the higher fieldstength at the RX site but this could shrink if you really go down to VLF frequencies, very short antennas and short distances. According to the author´s claims the quarz resonated system is usable for short range communication only and there the Q of L-tuned antennas will also grow to high values as well as the losses in the tuning circuit.

As soon as my ordered XTALs will arrive I´ll make further tests in the 4 kHz-range. If the results happen to differ very much from the preceding tests at 2.4 MHz I´ll report about it.

73 es Happy Easter,

Tom, DK1IS
4
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от ut7gh 21 Апрель 2019, 10:10:14 »
Красиво выглядит R7NT !  ;)
5
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от rw3adb 20 Апрель 2019, 23:01:27 »
Продолжают активничать японцы:
JA1CGM QRSS120 137.7783
JH1OFX DFCW60 137.776
JH1OFX OP32 137.498

принимать то у нас могут тока Саша, Юра, Сергей...
но 120я - внушает. можно попытать. тем более у всех прием почти круглосуточный.
6
On Thursday, April 18, 2019 07:31:13 PM DK1IS wrote:

 

SNIP

 

> Anyway, the idea is fascinating. Having no VLF crystals up to now, I

> made some preliminary tests with a randomly available HC-6-U quartz, QRG

> 2434 kHz, wavelength 123 m. And yes, it works!

>

> * TX: Sythesizer Schomandl MG100M, 300 Hz ... 100 MHz, smallest step

> 0.1 Hz, Ri = 50 Ohms, P = 10 dBm, output tied to first leg of

> quartz, alternatively direct to the antenna wire

> * RX: Perseus SDR with an active rod antenna on my garage, fed by a

> solar system, no external wire connections, air-line distance 100 m

> to my shack

> * Antena wire: 2 m or 4 m, laid out in the shack, tied to second leg

> of quartz, alternatively direct to the TX output

>

> Results with 2 m antenna wire:

>

> * with quartz resonator: fres = 2,433,908.8 Hz, RX level at resonance

> = - 63,1 dBm, - 3dB-bandwidth = 48.3 Hz resulting in Q = 50391

> * without quartz resonator: RX level = - 85,4 dBm resulting in a gain

> of 22.3 dB with quartz

> * comparision: my 13 m T-Marconi with top load 4 x 33 m, tuned to 2434

> kHz and fed by the synthesizer with 10 dBm results in a RX level of

> - 32.1 dBm ;-)

 

 

63.1 dBm - 32.1 dBm = 31.0 dB : the quartz adapted antenna radiated power is 1/1000 respect the T-Marconi, so the efficiency is 0.1%

 

Good DX ;-)

 

Claudio, IK2PII
7
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от R7NT 20 Апрель 2019, 20:54:02 »
multibeacon is ON
h:00 137541 OP32
h:32 137540 WSPR2
h:45 137602 WSPR15
E.sLoop + 200W Output
Продолжают активничать японцы:
JA1CGM QRSS120 137.7783
JH1OFX DFCW60 137.776
JH1OFX OP32 137.498
8
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от Сергей RA1ADF 20 Апрель 2019, 00:55:04 »
Пока не пытался. Но всё что было на грабере за эту зиму  это результат приёма на мой ППП и антенну о которой писал вот тут http://136.su/index.php/topic,339.0.html
9
Прием на длинных волнах / Re: Сегодня в эфире
« Последний ответ от rw3adb 19 Апрель 2019, 17:37:42 »
Радио любителей нет ни кого на диапазоне, так хоть на это полюбоваться  :)

не удалось определить что это?
10
Hi group,

a little bit OT, but the public interest seems to rise ;-)! At April 15, Roman, RW3ADB, pointed out here a similar article leading to a more detailled link:

https://www.nature.com/articles/s41467-019-09680-2.

The paper describes a kind of matching a low source impedance to a very high load impedance by using a piezoelectric resonator. Thus it is possible to feed an extremely short antenna with a very high voltage in resonance without using lossy L-C-circuits, resulting in a relatively "high" antenna current. Of course such a system has a very small bandwidth and is frequency-wise very sensitive to stray capacitances at the high-impedance side. The authors turn this to an advantage with regard to a fast capacitve re-tuning when using it in DAM systems (Direct Antenna Modulation). A second problem is that the crystal has to stand voltages in the 100 kV range which is impossible for commercially available quartz resonators. Therefore the authors use a special lithium niobat crystal at about 35 kHz with 94 mm length which is mounted in a chamber filled with hexafluoroethane gas - not so easy for a normal ham ...

Anyway, the idea is fascinating. Having no VLF crystals up to now, I made some preliminary tests with a randomly available HC-6-U quartz, QRG 2434 kHz, wavelength 123 m. And yes, it works!

    TX: Sythesizer Schomandl MG100M, 300 Hz ... 100 MHz, smallest step 0.1 Hz, Ri = 50 Ohms, P = 10 dBm, output tied to first leg of quartz, alternatively direct to the antenna wire
    RX: Perseus SDR with an active rod antenna on my garage, fed by a solar system, no external wire connections, air-line distance 100 m to my shack
    Antena wire: 2 m or 4 m, laid out in the shack, tied to second leg of quartz, alternatively direct to the TX output

Results with 2 m antenna wire:

    with quartz resonator: fres = 2,433,908.8 Hz, RX level at resonance = - 63,1 dBm, - 3dB-bandwidth = 48.3 Hz resulting in Q = 50391
    without quartz resonator: RX level = - 85,4 dBm resulting in a gain of 22.3 dB with quartz
    comparision: my 13 m T-Marconi with top load 4 x 33 m, tuned to 2434 kHz and fed by the synthesizer with 10 dBm results in a RX level of - 32.1 dBm ;-)

Results with 4 m antenna wire:

    with Quartz resonator: fres = 2,433,773.6 Hz, RX level at resonance = - 59 dBm. - 3 dB-bandwidth = 49.4 Hz resulting in Q = 49376
    without quartz resonator: RX level = - 75.4 dBm resulting in a gain of 16.4 dB with quartz

So it seems the best effects can really be achieved with very short antenna wires. The long range performance is in no way comparable with more fullsized antennas but for special applicatios the features could be interesting. For instance realising some capacitive feedback from the vicinity of the antenna rod could result in a small low power beacon with integrated matching - it even could be used as a presence detector with direkt frequency read out ...

- But yes, Rik, I`ll certainly will keep my Marconi - making QSOs on VLF costs enough efforts even when using a big antenna. But I´ve alredy orderd some VLF crystals on the bay ...

73 es Happy Easter!

Tom, DK1IS
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