Re: [Flexradio] PreSonus Firebox Output Voltage Descrepancies
I'm showing 2.5 v p-p on my o'scope. What's going on? Bob, K5KDN -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of root [knesbitt] Sent: Wednesday, April 05, 2006 5:40 PM To: FlexRadio@flex-radio.biz; [EMAIL PROTECTED] Subject: [Flexradio] PreSonus Firebox Output Voltage Descrepancies Folks, who's all measured their audio output voltages on the Firebox using the sound card output voltage test? I just had opportunity to run this test and found my Firebox is only pumping out 2.2 vac rather than the spec'ed 6.39 vac. Been working with [EMAIL PROTECTED] in an attempt to understand whats going on. Apparently others have noted this disparity in card output. Curious to know what other Firebox owners are finding. This is a potentially serious matter given the large disparity between the default value and the recorded level. I'm hesitant to apply this new value to the console settings for fear the level reverts to its higher output. To date however I have found nothing software/mixer-wise which would account for this. Kirb - VE6IV -- ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] PreSonus Firebox Output Voltage Descrepancies
At 03:40 PM 4/5/2006, root [knesbitt] wrote: Folks, who's all measured their audio output voltages on the Firebox using the sound card output voltage test? I just had opportunity to run this test and found my Firebox is only pumping out 2.2 vac rather than the spec'ed 6.39 vac. RMS vs PkPk voltage? Impedance of load? The webpage for the Firebox says 51 ohm output impedance and gives no full scale output voltage. Jim
Re: [Flexradio] PreSonus Firebox Output Voltage Descrepancies
I went back to the drawing board and tried to measure this myself and had trouble. Apparently our hard clipper that we added for the FireBox to prevent overdriving the transmitter is the culprit. Rather than a single tone @ 600Hz at 6.39VAC, you will get something like a square wave (nasty distortion) at 1.97VAC. To see the true full value, you can use the following procedure VERY CAREFULLY: 1. Disconnect the audio cable so that it is nowhere near the SDR-1000. ;) 2. Plug in a value to the V RMS right by the test button that is below 1.5V. 3. Run the test. 4. MAKE SURE to change the value back to the default setting before plugging the cable back into the radio!!! We will address this in the software in future releases. Eric Wachsmann FlexRadio Systems -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] radio.biz] On Behalf Of root [knesbitt] Sent: Wednesday, April 05, 2006 5:40 PM To: FlexRadio@flex-radio.biz; [EMAIL PROTECTED] Subject: [Flexradio] PreSonus Firebox Output Voltage Descrepancies Folks, who's all measured their audio output voltages on the Firebox using the sound card output voltage test? I just had opportunity to run this test and found my Firebox is only pumping out 2.2 vac rather than the spec'ed 6.39 vac. Been working with [EMAIL PROTECTED] in an attempt to understand whats going on. Apparently others have noted this disparity in card output. Curious to know what other Firebox owners are finding. This is a potentially serious matter given the large disparity between the default value and the recorded level. I'm hesitant to apply this new value to the console settings for fear the level reverts to its higher output. To date however I have found nothing software/mixer-wise which would account for this. Kirb - VE6IV -- ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex- radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] PreSonus Firebox Output Voltage Descrepancies
This is just not enough information to parse. 2.2 V under what conditions? what test? what is the input? PowerSDR hard limits the output in the case of the firebox to never go over a killing U2 voltage. Bob Bob Tracy wrote: I'm showing 2.5 v p-p on my o'scope. What's going on? Bob, K5KDN -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of root [knesbitt] Sent: Wednesday, April 05, 2006 5:40 PM To: FlexRadio@flex-radio.biz; [EMAIL PROTECTED] Subject: [Flexradio] PreSonus Firebox Output Voltage Descrepancies Folks, who's all measured their audio output voltages on the Firebox using the sound card output voltage test? I just had opportunity to run this test and found my Firebox is only pumping out 2.2 vac rather than the spec'ed 6.39 vac. Been working with [EMAIL PROTECTED] in an attempt to understand whats going on. Apparently others have noted this disparity in card output. Curious to know what other Firebox owners are finding. This is a potentially serious matter given the large disparity between the default value and the recorded level. I'm hesitant to apply this new value to the console settings for fear the level reverts to its higher output. To date however I have found nothing software/mixer-wise which would account for this. Kirb - VE6IV -- ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com -- AMSAT VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP/AMQRP, QRP ARCI, QCWA, FRC. ARRL SDR Wrk Grp Chairman Laziness is the number one inspiration for ingenuity. Guilty as charged!
