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## LF: Re: Drooping signal

 To: [email protected] LF: Re: Drooping signal "g3ldo" <[email protected]> Sat, 22 Feb 2003 21:44:13 -0000 <[email protected]> [email protected] <[email protected]>
 ```Hi John ``````Here's the visual evidence. ``````John Andrews sent (direct) a capture of my signal on the morning of the 22nd when a fragment was received by KL1X. I feel this droopy signal needs general explanation so I have replied via the reflector. John Thanks very much for the Jpeg. It turned out to be a much more useful capture than just a record of frequency instability. While I was transmitting I was monitoring my transmission on Argo and noticed the frequency drifting low. I think you know that I have my transmitter in a shed at the bottom of the garden, together with the DDS driver. At this time of the year the temperature can drop to as low a -8C. The DDS frequency is sensitive to temperature but if the shed stays cold it is unaffected by the transmitter being on or my presence. When the temperature in the transmitter shack is around 0C then heat from the transmitter can raise the temperature by about 1 to 2 deg C. The DDS is moved 0.1Hz per change of 1 deg C. When I noticed the frequency downward drift I went down and opened the door of the transmitter shed - hence the reversal of frequency drift. Now while this is hardly good engineering practice the signal characteristic enabled me to compare it with the signal received by KL1X and confirm it was a D he received at the lowest part of the dip of the frequency drift. The plan is to eventually have the DDS unit, plus a divide by 10 circuit and driver, in the house shack by the side of the receiver. This will give me 0.1Hz resolution and more stability - and less 'characteristic'. Regards, Peter, G3LDO e-mail <[email protected]> Web ```
 Current Thread LF: Re: Drooping signal, g3ldo <= LF: Re: Re: Drooping signal, John Andrews LF: Re: Drooping signal, g3ldo LF: 137.773kHz Feb 25/26th., Steve Dove LF: Re: 137.773kHz Feb 25/26th., John Andrews LF: 137.773kHz Feb 25/26th in CT, Jay Rusgrove LF: Re: 137.773kHz Feb 25/26th in CT, John Andrews LF: 137.773kHz Feb 25/26th., Steve Dove