LF: MF WSPR, 472 vs 501.

["Dave G3WCB." <ganymede444@btopenworld.com>]

Hello Rik.

 

I can still monitor 501 kHz if you want to perform some comparative testing some time. I'm using the same Tee antenna at 5m, with a 20m top as before. I've just added a small loading coil in series with the original 501 kHz loading coil to tune down to 472 kHz.

 

73, Dave G3WCB IO91RM

-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Rik Strobbe
Sent: 06 October 2013 09:57
To: rsgb_lf_group@blacksheep.org
Subject: RE: LF: MF WSPR, crazy

Hello Jim,

 

over the past weeks I completed my new rig, that can be used to transmit on 501 and 472 kHz (we still have the 501-504 kHz segment available in Belgium).

In theory the radiation resistance of a short vertical antenna increases with the square of the frequency, so going from 501 kHz to 472 kHz will make Rrad drop by 11% (= 0.5dB).

Further I noticed that the loss resistance increased from 71 Ohm (on 501 kHz) to 76 Ohm (on 472 kHz) = +7% (=-0.3dB).

So overall the efficiency will drop by about 0.8 dB (or I will need 20% more power to get the same ERP).

 

73, Rik  ON7YD - OR7T

 

PS: QRM level (energy saving lamps, switched PSU's etc...)  is most of the time lower on 472 kHz compared to 501 kHz

---

Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens James Cowburn [james.cowburn@virgin.net]
Verzonden: zondag 6 oktober 2013 9:12
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: RE: LF: MF WSPR, crazy

Hi All, while I’m not renowned for having the most efficient or qro MF station, I have noticed that 472 is not as good for range, for me at least,  as 500 was.  I used to be able to be spotted by Finbar, John PG, Lubos etc but these days, XIZ represents real dx!!

 

Even after rejigging antenna etc its still not brilliant. 

 

Cheers all

 

Jim G7NKS

 

---

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Graham
Sent: 06 October 2013 01:13
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: MF WSPR, crazy

 

 

 

This  was  -21

 

090325 0050   9 -21  1.5   0.503938  G0NBD IO83 13

 

 

Hello Graham,

 

You still had 10 DBs to spare for a decode!!! Try 2 milliwatts...

 

Looks like 155,700 miles per watt...

 

Good on ya... PSE QSL VIA E-MAIL... ( hi hi )

 

 

Dave @ WD2XSH/17

 

 

From: Graham

Sent: Sunday, October 06, 2013 1:08 AM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: MF WSPR, crazy

 

Im sure the  band  was  in better  shape  in those  days  ?

 

G,)

 

2009-03-25 00:56	G0NBD	0.503938	-23	0	IO83lk	+13	0.020	AA1A	FN42pb	5012	3114
2009-03-25 00:56	G0NBD	0.503937	-23	0	IO83lk	+13	0.020	DJ6YD	JO42bg	760	472

 

 

From: Stefan Schäfer

Sent: Friday, October 04, 2013 11:53 PM

To: rsgb_lf_group@blacksheep.org

Subject: LF: MF WSPR, crazy

 

Actually no need to inform about it, because everyone seems to be QRV now :-)
Anyway, the hell is going on on MF WSPR!

Got decodes by 71 stations in the last 2 weeks and 47 in the last 24 hours. Need to post that here, i'm impressed.

Tnx to all.

73, GL, Stefan/DK7FC

71 spots:

Timestamp	Call	MHz	SNR	Drift	Grid	Pwr	Reporter	RGrid	km	az
2013-10-03 00:00	DK7FC	0.475685	-28	0	JN49ik	1	RX3DHR	KO94ks	2125	62
2013-10-04 22:42	DK7FC	0.475686	-15	0	JN49ik	1	OH6JKN	KP22xk	1789	30
2013-10-02 18:24	DK7FC	0.475686	-26	0	JN49ik	1	LB9YE	JP54pu	1721	4
2013-10-04 01:12	DK7FC	0.475687	-26	0	JN49ik	1	SV8RV	KM07ks	1621	139
2013-10-04 03:30	DK7FC	0.475688	-27	0	JN49ik	1	EA1FBU	IN52qg	1556	246
2013-10-02 04:00	DK7FC	0.475687	-2	0	JN49ik	1	ES5AM	KO38gr	1547	41
2013-10-02 03:18	DK7FC	0.475686	-16	0	JN49ik	1	EA5DOM	IM98wn	1398	213
2013-10-04 02:36	DK7FC	0.475688	-6	0	JN49ik	1	SM0FGT	JO89xg	1244	25
2013-10-04 02:00	DK7FC	0.475685	-6	0	JN49ik	1	IZ7PDX	JN80ps	1174	142
2013-10-02 03:06	DK7FC	0.475687	-13	0	JN49ik	1	IZ7SLZ	JN80nu	1159	142
2013-09-29 00:00	DK7FC	0.475688	-27	0	JN49ik	1	EA2HB	IN93ah	1063	234
2013-10-04 21:48	DK7FC	0.503891	-18	0	JN49ik	1	G4VQP	IO70je	1001	280
2013-10-04 22:36	DK7FC	0.475685	-10	0	JN49ik	1	G3XKR	IO70ux	940	285
2013-10-02 20:48	DK7FC	0.475685	-10	0	JN49ik	1	G0MJI	IO83ni	913	303
2013-10-02 03:18	DK7FC	0.475685	-28	0	JN49ik	1	SQ2BXI	JO94gj	870	47
2013-10-04 02:24	DK7FC	0.475670	+2	0	JN49ik	1	M0EMM	IO82sq	859	299
2013-10-04 13:30	DK7FC	0.475685	-28	0	JN49ik	1	G0HNW	IO93cn	858	306
2013-10-02 03:18	DK7FC	0.475685	-2	0	JN49ik	1	G8HUH	IO81mg	851	288
2013-10-03 00:42	DK7FC	0.475687	-4	0	JN49ik	1	G8HUH/2	IO81mg	851	288
2013-10-02 22:12	DK7FC	0.475685	-6	0	JN49ik	1	M0PPP	IO93gm	837	307
2013-10-04 22:30	DK7FC	0.475685	-23	0	JN49ik	1	M0PAF	IO93gm	837	307
2013-10-03 04:18	DK7FC	0.475685	-14	0	JN49ik	1	G0KTN	IO81ti	813	289
2013-10-04 01:12	DK7FC	0.475688	-13	0	JN49ik	1	M0ITF	IO81wv	810	294
2013-10-02 03:12	DK7FC	0.475685	-6	0	JN49ik	1	G8JNJ/A	IO90hx	737	287
2013-10-03 16:06	DK7FC	0.475683	-25	0	JN49ik	1	G3NZP	IO91	726	292
2013-10-04 22:48	DK7FC	0.475685	-8	0	JN49ik	1	G3XIZ	IO92ub	697	298
2013-10-04 21:54	DK7FC	0.475685	-6	0	JN49ik	1	G3WCB	IO91rm	694	293
2013-10-02 19:36	DK7FC	0.475685	-7	0	JN49ik	1	G4CAO-2	IO91si	683	292
2013-10-03 00:00	DK7FC	0.475685	-13	0	JN49ik	1	G4CAO	IO91si	683	292
2013-10-02 04:12	DK7FC	0.475688	+8	0	JN49ik	1	G4KPX	JO02dj	675	302
2013-10-04 19:24	DK7FC	0.475685	-14	0	JN49ik	1	I5MXX	JN53ju	641	165
2013-10-02 18:00	DK7FC	0.475675	-24	0	JN49ik	1	I5EFO	JN53hu	638	166
2013-10-04 22:36	DK7FC	0.475685	-7	0	JN49ik	1	G6AVK	JO01ho	620	296
2013-09-29 00:18	DK7FC	0.475665	-11	0	JN49ik	1	G3TYB	JO01ii	605	294
2013-10-04 01:12	DK7FC	0.475685	-6	0	JN49ik	1	M0ELS	JO01	593	295
2013-10-04 17:12	DK7FC	0.475684	-13	0	JN49ik	1	F59706	JN07th	574	248
2013-10-04 01:12	DK7FC	0.475686	+6	0	JN49ik	1	IW4DXW	JN64bw	563	151
2013-10-04 10:42	DK7FC	0.475685	-29	0	JN49ik	1	G6GJT	JO01ri	556	295
2013-10-01 02:42	DK7FC	0.475689	-1	0	JN49ik	1	DF2FF	JO44th	546	6
2013-10-03 14:06	DK7FC	0.475690	-18	0	JN49ik	1	F6FLE	JO00tr	525	289
2013-10-01 04:06	DK7FC	0.475684	+5	0	JN49ik	1	DK6XY	JO53jv	516	15
2013-10-02 03:30	DK7FC	0.475690	+1	0	JN49ik	1	DG3LV	JO53gv	512	14
2013-10-02 20:12	DK7FC	0.475698	-20	-1	JN49ik	1	DL7AIE	JO62pt	493	39
2013-10-02 05:36	DK7FC	0.475677	-9	0	JN49ik	1	DF2LS	JO53dr	490	12
2013-10-04 18:24	DK7FC	0.475655	-5	0	JN49ik	1	OK1DWF	JO70qb	484	79
2013-10-04 22:18	DK7FC	0.475685	+2	0	JN49ik	1	PA0A	JO33de	449	339
2013-10-04 22:36	DK7FC	0.475684	-20	0	JN49ik	1	PA0LPN	JO22ux	446	333
2013-10-04 15:54	DK7FC	0.474935	-13	0	JN49ik	1	PA3FNY2	JO22nc	389	321
2013-10-04 17:06	DK7FC	0.474935	-10	0	JN49ik	1	PA3FNY	JO22nc	389	321
2013-10-01 13:00	DK7FC	0.475685	+6	0	JN49ik	1	F6CNI	JN19qb	389	266
2013-10-04 16:54	DK7FC	0.474935	-6	0	JN49ik	1	PA3FNY\2	JO22nc	389	321
2013-10-04 22:36	DK7FC	0.475685	+2	0	JN49ik	1	PA3ABK/2	JO21it	386	315
2013-10-02 03:42	DK7FC	0.475685	-6	0	JN49ik	1	DL-SWL	JO52hp	381	20
2013-10-02 19:36	DK7FC	0.503886	+4	0	JN49ik	1	IN3EFR	JN56pl	381	149
2013-10-04 22:42	DK7FC	0.475686	-4	0	JN49ik	1	IN3FCI	JN56qm	380	148
2013-10-02 04:24	DK7FC	0.475630	-21	0	JN49ik	1	NL8992	JO32fl	373	336
2013-10-04 02:12	DK7FC	0.475685	0	0	JN49ik	1	PI4THT	JO32kf	336	338
2013-10-04 22:30	DK7FC	0.475686	-3	0	JN49ik	1	OR7T	JO20ix	332	303
2013-10-04 17:54	DK7FC	0.475685	0	0	JN49ik	1	DL4RAJ	JN68kj	326	109
2013-10-04 22:30	DK7FC	0.475684	-2	0	JN49ik	1	DF6MK	JN68ik	313	109
2013-10-01 13:48	DK7FC	0.475685	-17	0	JN49ik	1	DC0DX	JO31lk	255	332
2013-10-02 18:42	DK7FC	0.475685	+9	0	JN49ik	1	HB9FGK	JN37	253	211
2013-10-02 17:18	DK7FC	0.475682	-3	0	JN49ik	1	F6ACU	JN38fc	222	229
2013-10-04 21:24	DK7FC	0.475685	-17	0	JN49ik	1	HB9LFT	JN47cl	221	190
2013-10-04 22:18	DK7FC	0.475685	+1	0	JN49ik	1	DL1DBC	JO41bi	217	349
2013-10-04 20:30	DK7FC	0.475712	-4	0	JN49ik	1	DK6NI	JN59ln	163	84
2013-10-04 17:12	DK7FC	0.475685	-14	0	JN49ik	1	DC0VD	JN39qw	111	301
2013-10-01 13:54	DK7FC	0.475685	-11	0	JN49ik	1	DJ7KA	JN48mn	100	166
2013-10-03 22:24	DK7FC	0.475685	+9	0	JN49ik	1	DD7PC	JN49ax	77	322
2013-10-02 19:42	DK7FC	0.475685	+13	0	JN49ik	1	DK2DB	JN48fw	58	198
2013-10-02 03:18	DK7FC	0.475685	+12	0	JN49ik	1	DK6UG	JN49cm	37	285

 

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2014.0.4142 / Virus Database: 3604/6724 - Release Date: 10/04/13