Hi Johan and all LF-ers...
It's working fine. I calibrated my DDS with the reference frequency
of DCF39 on 138.830 and it looks good. On Albertos (I2PHD) spectrogram is my
frequency exact on 135.922 kHz. Just received an E-mail from CT1DRP, he
detected a short sequence unfortunately not readable easily but on the
frequency. So, thanks all for the help. I'll continue in my test. Best
regards...
73 de Rich OM2TW
-----Original Message-----
From: Johan Bodin [mailto:[email protected]]
Sent: Thursday, December 20, 2001 5:28 PM
To: [email protected]
Subject: LF: Re: DDS calibration...
Rich,
It's possible to save this calibration in EEPROM ?
Anybody knows how to do it ?
Yes, I wrote the firmware...
1.
If the CAL switch is held down at power-on, the default calibration value
(corresponding to 25.0000... MHz clock) is loaded into EEPROM and the
display will show "CAL=Default" for a few seconds.
2.
If the CAL switch is pressed temporarily during operation, the software
enters calibration mode and the calibration constant can be changed
with the VFO knob. Just press the CAL switch again to store the new
calibration in EEPROM and resume normal operation.
If you see "CAL=Default" on the display every time you start the DDS,
there is a problem with the CAL switch. The CAL switch should be a
normally open momentary pushbutton that connects PIC pin 11 (RB5)
to ground via a 470-820 ohm resistor.
73 de Johan SM6LKM
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