Re: LF: 475 kc Exiter

[M0FMT <m0fmt@yahoo.co.uk>]

Ok Graham

 

I will try to talk to Eddie, my beacon is HB PIC built. I need to know the type of on off keying mark / space. I will take a look at it on the scope to see how the code is applied and see if I can emulate it in code form.

 

Ok about power I will start at the current power level using my Lap top and will let you know via this medium on BS and Yahoo when its up and running plus as close as I can get the carrier frequency. I can get onto the Opera channel using a DSS and xtal mixer but power much lower. The xtal mixer is a valve rig using 6.50-6.00=.5+/- VXO PA 6CL6 tube video bottle which I may try for a laugh (ancient and modern.....:-).

 

73 es GL Pete M0FMT IO91UX

From: Graham <g8fzk@g8fzk.fsnet.co.uk>
To: rsgb_lf_group@blacksheep.org
Sent: Thursday, 31 May 2012, 19:25
Subject: Re: LF: 475 kc Exiter

Ok Pete,

 

Well  if your  set up on a  different  frequency  , if you  have a  date/ time   for a  transmission, stations can  re tune  , all  we  need  to  know  is the  carrier  frequency, then  can  work out the  correct  dial  frequency  for  RX  ......   would  give  you  a  idea  as to  your  coverage  ....  thats  if you  can on/off  key  the  carrier , or  is the  beacon pic  contolled, which  case , may be  the  code  change  would be the  most  simple  option ?

 

Should  not  need  much  over  10 watts  ?   you  should  find  1 watt enough  with  that  size of  Ae

 

Not  used the  PIC  code  facility  in the  software  , but  it  will  encode  your  call-sign   for  Tx  , I think  Eddie  uses it  for  his qrpp  beacon, should  be  able to  give  you  pointer  if  need  be  , Andy also uses  it  for  his LF/MF beacon

 

73 -G..

From: M0FMT

Sent: Thursday, May 31, 2012 7:13 PM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: 475 kc Exiter

 

Hi Graham

 

I will digest your mail and thanks for so much info. I have a beacon that runs on 500kc/s it is not in the Opera band. It is currently at about 10Watts O/P to an inverted "L" up about 35ft x 128ft lng, running QRSS and 12WPM. Clearly seen on the Birmingham Grabber when on. Initially my plan is to run Opera base upon your information. The operating times will be dependent upon Internet usage here and reports. I will also QSY to the Opera frequency in due course. Now you have confirmed it is not a linear mode I will commit my lap top for a period of time to Opera operation and increase power to 40Watts +/-. If I can get a HEX code for a PIC then it will be on Opera more often.

 

I will let you know the progress.

 

Once again thanks for the info to date.

73 es GL Pete M0FMT IO91UX

From: Graham <g8fzk@g8fzk.fsnet.co.uk>
To: rsgb_lf_group@blacksheep.org
Sent: Thursday, 31 May 2012, 17:20
Subject: Re: LF: 475 kc Exiter

R  Pete !

 

I think the  answer is  42  !

 

There is a  user group  >  http://groups.yahoo.com/group/O_P_E_R_A_/,    Open to  all  to  view , with  pdf in the  files section  outline  the  data  coding of the  mode. 

 

There is a  good  user guide/ intro   at   http://www.obriensweb.com/operaguide.html

 

Keying  is   designed  round  the  characteristics  of a  CW  transmitter ,

 

There  are  TWO conventional  and ONE    Pic   methods of  controlling a transmitter  ,

 

A)    By  using the  COM-Port   CW  keying  , by way of   transistor  switch  , to  key  the  Tx  as  per  normal CW

 

B)    By  audio  drive  from the  sound-card , to  SSB  exciter , producing  on/off  single  frequency carrier.

 

C)    The  windows  software  has a  PIC code  generator , that  may  be used to  control  a  PIC based  'Beacon system'

 

 

There  is  no  PIC provision  for the  decoding  of the  signals

 

Transmission  is  by  way of   ON-OFF keying  of a  single  carrier  frequency ..clever On/Off keying Magic !

 

Decode is possible  with  up-to  50% data  loss  , the loss  can  be  randomly  along the  TX time  line , the  S/N   reading  is  calibrated  against the   Sim-Path software  and shows  6 dB  less than  wspr  or  fldigi   ,  i.e   -20 s/n  Opera decode  , would be  -26 dB  using  wspr  , however , the  S/N is  the  average  along the  time  line  and not the  peak  value

 

At the moment  , there  is  no  'dedicated'  data  server  , however the  PSK-Reporting  system  is able to  down load  data  as a  log-file. ( still looking  for  some one to have a  go at  making one )

 

There is  no  need  for  internet linking  or  time  locking to  operate  the  system  ,  the  internet provider's  the  distribution  of the  decode data  and  TX beacon's  are  also  distributed  via the  internet to  alert of  activity.   

 

Tx  and  Rx  stations  with  web linking  are  displayed on the psk-map  as  are  decodes of  -NON-   web linked TX  stations

 

The  operating  frequency's  are  defined  as  'Dial  set  USB'  , change of  mode  , also  changes the  TX frequency , so  if using  VFO/DDS  etc ,  the  correct  off  set  must  be  added  to  ensure  the  signal  falls  in the  RX pass band ,

 

When  using the  windows  based  software , the  TX carrier  frequency is placed  in the  lowest  s/n  area  of the   pass  band  , by a   scanning  routine  , active  during reception , this  is  to  prevent  collisions of  TX's  and to  avoid  heterodynes   and  other  carrier  based  band  users.

 

QSO mode  is  able to send 15 chrs using the  same  encoded  data  system and is a live  keyboard  data  mode.

 

Data  recovery  (local) is only  by  cut  and paste  at the  moment.   

 

Op is  the  first  'Plug and Play'   data  / beacon  mode  ,   just unplug the  mores key and  play   away   hihi

 

73 -G..

 

 

 

 

 

From: M0FMT

Sent: Thursday, May 31, 2012 7:05 AM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: 475 kc Exiter

Hi Graham

Is there any proper documentation for this Opera stuff? Like description of the method of Keying and how the logging system works. How do you get qso data off the application other than screen dumps which seems a bit crude. There are software buttons but they don't all work as advertised.

 

Can you tell me where the full documentation is kept?

Can you tell me the Keying principle? I have not put the PC SC output on the scope but there must be an easier way to get at the info. Is it FSK or Phase shift or some clever On/Off keying or Magic?

Is there a web data base or is the screen info just a one shot?

Do I need an Internet connection during Beacon or QSO ing? With my issues concerning Good Old BT and their 19th century technology, rusty copper and wet string, in the far flung out posts of North Hertfordshire that can't be done, so does that preclude full use of this system.

Or is it all a secret and one has to dig into the application? Info in README is sparse.

Has there been any projects to put this application of PIC processor for say TX Beacon mode? Or RX for that matter?

 

There are more questions but any help would be of interest. Now that I have managed to probably defeat BTs best efforts to keep me off 500kc/s I would like to explore this mode a bit more. Thanks.

73 es GL Pete M0FMT IO91UX

From: Graham <g8fzk@g8fzk.fsnet.co.uk>
To: rsgb_lf_group@blacksheep.org
Sent: Thursday, 31 May 2012, 0:02
Subject: Re: LF: 475 kc Exiter

TX500 is not supporting WSPR or Opera

Opera is a single frequency  on/off    CW key replacement  mode , if it  can
send  CW or  QRSS  , then  it can  send  Opera  via the  com-port keying
facility, as many of the  MF/LF  stations  are  so  doing.

WSPR on the  other  hand is  FSK based and requires , either  audio>Rf
translation  or  DDS  excitation , each has its  own uses , the design
requirement /  concept  of  Opera  was  a  'Data mode'  ' To be  sent via a
normal CW Tx'

G..



--------------------------------------------------
From: "Clemens  Paul" <cpaul@gmx.net>
Sent: Wednesday, May 30, 2012 11:15 PM
To: <rsgb_lf_group@blacksheep.org>
Subject: Re: LF: 475 kc Exiter

> Uwe,
>
> here an Email from Juma from 2/2012 1regarding further developments:
>
>>Hello Clemens,
>>Thanks for your interest in JUMA TX500.
>>TX500 is not supporting WSPR or Opera. We will consider new transmit modes
>>in the future.
>
> 73
> Clemens
> DL4RAJ
>
> ----- Original Message -----
> From: "Warren Ziegler" <wd2xgj@gmail.com>
> To: <rsgb_lf_group@blacksheep.org>
> Sent: Wednesday, May 30, 2012 7:45 PM
> Subject: Re: LF: 475 kc Exiter
>
>
> Uwe,
>
>  The Juma 500 is a FB little transmitter, lots of built-in features
> (synthesizer, keyer, swr bridge, receive preselector, receive
> converter) in a very small package. It is capable of more than 60W
> out, I have run it with 15vdc (which is in-spec) and with a 30 ohm or
> so antenna impedance you can get 100W out all day and all night with
> no complaints.
>
> 73 Warren K2ORS
>
>
> On Sun, May 27, 2012 at 3:39 AM, Uwe Wensauer <uwe.wensauer@gmx.de> wrote:
>> What do You think about the JUMA TX500 TransmitterI
>>
>> In my eyes a small Rig with 60 Watt and built in Converter.
>>
>> By the way, have a look at the filters in use – easy to built an
>> duplicate
>>
>> Uwe, dk1kq
>
>
>
> --
> 73 Warren K2ORS
> WD2XGJ
> WD2XSH/23
> WE2XEB/2
> WE2XGR/1
>
>
>
> -----
> E-Mail ist virenfrei.
> Von AVG überprüft - www.avg.de
> Version: 2012.0.2178 / Virendatenbank: 2425/5033 - Ausgabedatum:
> 30.05.2012
>
>
>