Mark, Depending on the age of your SDR-1000, it may or may not have L14 installed on the PA board across the connections going to the RF output connector. This was originally a static drain but has since been removed.
I had a problem similar to yours that was caused by L14 being zapped and left a carbon path between the pads. You might check this out. 73, Bob, K5KDN -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Mark Amos Sent: Tuesday, July 04, 2006 11:54 AM To: 'FlexRadio' Subject: [Flexradio] Transmit power calibration problems Help! I'm having a strange problem with my SDR1000 and output power. When I click 'tune' in PowerSDR (1.6.2 - I no longer have any other versions installed to test with...) the output of the SDR1000 (as declared by the internal power meter and an external power meter with dummy load) is over 100 watts - regardless of the tuning power setting. Same with transmit power (no matter what I set the power output setting, it's still over 100 watts.) I tried power calibration and it never seems to finish (power never gets down to 60 watts as the gain setting keeps rising the power seems to bounce back and forth somewhere between 70 and 80 watts.) When I do the audio output power test and measure RMS output power with two different multimeters (an FET frontend analog meter and an Extech digital meter) I only see about 2 volts (as opposed to the 6.39 volts that PowerSDR seems to think I should see from the FireBox.) I get just over 2 volts with the analog meter and show 1.98 volts with the digital meter. I thought maybe it was a cable-seating problem, so I swapped cables and wiped them with Deoxit, but no difference.) Re-installed PreSonus drivers (1.20 to 1.21) no difference. I was using a USB adapter so I swapped back to parallel port adapter - no difference. I verified the dummy load impedence (50ohms) with a palstar bridge. I was having some problems with an antenna tuner prior to this issue and I'm thinking that maybe I cooked the power metering circuit in the SDR(?) or something like that. I thought I'd check with the list before going back to the D44 for additional testing. I'm reluctant to swap out the FireBox (because I don't have a spare $300 to test it.) Any other ideas/suggestions? Mark _______________________________________________ FlexRadio mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com _______________________________________________ FlexRadio mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
