No, the only Tx I have for LF these days is the 700 Watt job. Its
switch mode .
Changing taps may bring it down to 300 watts, but no less.
I'll have a look though the junk-junk box (stuff destined for rallies
/ dismantling etc) - may still have a QRP Tx from years gone by,
probably a 73kHz one that should go at 137
But it would be nice to be copied in the US using the QRO. Something
I'd never thought likely with this antenna ever before.
Andy
www.g4jnt.com
On 10 January 2012 21:21, Graham <[email protected]> wrote:
> Opps
>
> Spent so long on op2 , just realises your OP8
> OP8 -32dB Op31 -38 dB S/N Mean (not peak) 21:07 136 G8IMR de G4WGT Op8 314
> km -18 dB in Coppull, nr Preston
>
> That is +20 dB over the s/n limit .. you should be ok down to 600 >>
> 60 >> .... 6 watts
> Can you reduce to that level ?
>
> G..300
>
>
>
>
> --------------------------------------------------
> From: "Andy Talbot" <[email protected]>
> Sent: Tuesday, January 10, 2012 8:04 PM
> To: <[email protected]>
> Subject: Re: LF: opera 137 beacon going
>
>
>> 600 Watt of Rf to 7m high Tee with Gnd loss about 80 ohms. I reckon
>> about -40dBi gain so call it a few tens of mW
>>
>> Andy
>>
>> On 10 January 2012 19:58, Graham <[email protected]> wrote:
>>>
>>> Reaching Gary with +7 dB in hand , what is the carrier power ?
>>>
>>> Be very interesting to see what the s/n would be from MAL
>>> over similar range and similar path , with all that wire out
>>> should be able to catch Andy's beacon into the +dB scale
>>>
>>> G..
>>> 18:49 136 G8IMR de G4WGT Op8 314 km -19 dB in Coppull, nr Preston
>>>
>>> --------------------------------------------------
>>> From: "Andy Talbot" <[email protected]>
>>> Sent: Tuesday, January 10, 2012 4:06 PM
>>> To: <[email protected]>
>>> Subject: LF: opera 137 beacon going
>>>
>>>> Having had to modify a 137kHz source to be able to generate on-off
>>>> keying, I'm transmitting a signal using 2.048s symbol mode on 137420Hz
>>>> 33% duty cycle (for now)
>>>>
>>>> This is based around my PIC generator for the mode
>>>> Details at http://www.g4jnt.com/PIC_Opera_Source.pdf and
>>>> http://www.g4jnt.com/OperaBeacon.zip
>>>>
>>>> As its an independent source, with no PC in the Tx chain - no IP
>>>> packets will be sent to t'web showing the details
>>>>
>>>> and its definitely gettign out....
>>>>
>>>> 15:46 136 G8IMR de F6CNI Op8 391 km -28 dB in 136 kHz dial nr Paris
>>>>
>>>>
>>>> Andy
>>>> G4JNT
>>>>
>>>
>>
>
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