See my comments in-line below. -Tim ---- Integrated Technical Services www.itsco.com
"Si fractum non sit, id reficere" -Unknown Roman consultant -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Fleetwood Sent: Friday, December 29, 2006 6:24 AM To: [email protected] Subject: [Flexradio] Delta 44 BBox I have a 1 watt SDR 1000 purchased six months ago. I feed it into the driver and PA of an otherwise defunct Heath SB401. Question 1: I had trouble with the Rx randomly not coming back after tx. Attaching grounding leads to the Delta 44 breakout box seems to have cured this problem. [Tim Ellison>] Grounding and ground loops have been a problem with the D44 breakout box I had a peep inside the box and am a bit puzzled that the barrels of the jack sockets do not seem to be grounded, but connected to the sleeve contact via a resistor and capacitor - can someone explain to me what is going on here please? [Tim Ellison>] It is a way of "cheating". The D44 inputs are unbalanced at the card, so they use this arrangement to allow people to connect balanced TRS connectors to the sound card. My leads use mono plugs so what does the sleeve do? I see reference to a Delta 44 breakout box eliminator kit by Eric AA4SW, but can't seem to find any more info on this. [Tim Ellison>] Tony KB9YIG is offering the Delta-44 interface kit. Five hundred kits will be provided in this kit run. The kit will come with all the parts for a module including the two-pin headers and jumpers for the external cable grounding options. Additionally an extra 1206 ferrite filter and an extra 1206 capacitor will be provided in each kit for loss of one of the parts during kit building. Orders can now be placed, with Tony directly at: [EMAIL PROTECTED] I also wonder if the box can be modified to further improve RF immunity? [Tim Ellison>] Probably, but the breakout box eliminator is the way to go. Question 2: On the Delta 44 control panel, hardware, what does "Codec sample rate" do - the quick start guide has it on 48,000 but I find it flips away from this setting to 22,050 when I save the settings. [Tim Ellison>] This is the sampling rate. Unless you have the rate "locked" the D44 card will auto sense sampling rates and change to match the application. It isn't anything you need to worry about Question 3: Finally, I get excellent reports on my transmit audio, but I am a bit disappointed with the receiver, it seems little better than my ancient Kenwood TS820S at copying weak ssb signals on 20m. I wonder if it is working correctly and what things might be worth checking? The PC is an AMD Athlon XP 2400+ 2.0GHz with 1 GB ram. [Tim Ellison>] Can you describe how and what you have used to calibrate your SDR-1000? Also, check the output signal levels of the D44 are -10 dBV. Refer to the D44 QSG http://kb.flex-radio.com/article.aspx?id=10047&cNode=0O0B7Q 73 Mike, VK1AMF / G3XEF Mike Fleetwood Canberra, Australia. Worldwide email address is: [EMAIL PROTECTED] _______________________________________________ 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
