If you have a radio with adjustable CW mode like most SDRs, and the
RA1792, its easier to use CW mode. Tune to the centre frequency of
interest, set the filter appropriately and the BFO to the decoders
preferred tone.
For last nights listening, my SDR-IQ was set to CW mode, audio lower
freq 400Hz, upper freq 1600Hz, BFO 1000Hz
(You can set arbitrary upper/lower linits on the SSB filter as well on
Spectravue), but guess who initially fell foul of seeing 503kHz
specified and assumed it meant the same as the JT65A freq the other
night. So, on seeing the tones not where they 'should' have been and
re-reading the email post...
Must get round to writing a WSPR PIC routine for the AD9852 DDS
similar to my existing JT65 beacons.
Andy G4JNT
www.g4jnt.com
2009/1/3 Graham <[email protected]>:
> Tx bandwidth and out of band signals ,
>
> Well after picking up the toys from around the cot and tidying up the baby
> finally fell asleep ,silence finally ensued, a little familiarisation with
> the way the radio works may help, just because the rx dial displays a
> frequency out side the allocated band, doesn't actually mean the signal is
> out side the band .. its all to do with filter shape factor and the
> placement of the filter .... bit like dougle asking farther ted, are all the
> cows in the field the same size as his little plastic toy one... no dougle,
> this ones in your hand and those are far away , right ted came the quick
> reply .from a still confused dougle .
>
>
> --------------------------------------------------
> From: "mal hamilton" <[email protected]>
> Sent: Friday, January 02, 2009 7:54 PM
> To: <[email protected]>
> Subject: LF: Re: Low power olivia beacon 503 khz cent freq
>
>>
>> OM
>> Your transmission is outside the band limit, spreading to 504.6 khz.
>> I can see why OFCOM are concerned about stricter control concerning data
>> mode bandwidth.
>> g3kev
>>
>> ----- Original Message ----- From: "Graham" <[email protected]>
>> To: <[email protected]>
>> Sent: Friday, January 02, 2009 6:30 PM
>> Subject: LF: Low power olivia beacon 503 khz cent freq
>>
>>
>>> Olivia 1 khz x 32 tone
>>>
>>> centre frequency 503 khz
>>>
>>> tx mode usb
>>>
>>> power 30 watts tune signal
>>>
>>> Will send for next few hours
>>>
>>> Reports welcome
>>>
>>>
>>> Graham
>>>
>>>
>>>
>>>
>>
>>
>>
>> --------------------------------------------------------------------------------
>>
>>
>>
>> No virus found in this incoming message.
>> Checked by AVG - http://www.avg.com
>> Version: 8.0.176 / Virus Database: 270.10.2/1871 - Release Date: 1/1/2009
>> 5:01 PM
>>
>>
>>
>
>
>
>>
>> No virus found in this incoming message.
>> Checked by AVG - http://www.avg.com
>> Version: 8.0.176 / Virus Database: 270.10.2/1871 - Release Date: 1/1/2009
>> 17:01
>>
>
>
>
|
