All,
The 70 cm Receiver spur problem has been solved. Click here http://www.juanr.com/pages/hobbies/ham_radio/Eagle/CAN-Do_Noise_Troubleshoo ting.htm for details.
73,
Juan
WA6HTP
Hi Juan,
This is fantastic!
Please try one more experiment. Pass the module current through the current measuring circuit on the CAN-Do! while bypassing the switch transistor (you could just short across the switch transistor) and see if the problem reappears.
If you end up having to use the user pins, you will need to add current measuring circuitry to your module. While this is no big deal, its one more thing you might not have to do.
Chuck
Juan Rivera wrote:
All,
The 70 cm Receiver spur problem has been solved. Click here http://www.juanr.com/pages/hobbies/ham_radio/Eagle/CAN-Do_Noise_Troubleshooting.htm for details.
73,
Juan
WA6HTP
Via the Eagle mailing list courtesy of AMSAT-NA [email protected] http://amsat.org/mailman/listinfo/eagle
Folks
The 70 cm Receiver spur problem has been solved. Click here
http://www.juanr.com/pages/hobbies/ham_radio/Eagle/CAN-Do_Noise_Troubleshoo ting.htm
for details.
This is very interesting. FWIW in the original SDX PSU design I had in San Francisco last year is an SMPS using the LM2672 device. These can be fitted with an AC coupled SYNC signal to override the internal default SMPS frequency. I selected 375kHz for my unit (6MHz divided by 16) to ensure its harmonics were outside the 10.7MHz IF passband. If the external SYNC fails the internal SMPS oscillator takes over.
Cheers, Howard
participants (3)
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Chuck Green -
Howard Long -
Juan Rivera