[Flexradio] Flex 3000 Signal meter
I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? Roger G0IUW ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
Mine has the same type of behavior, I can't remember the specifics, but the Smeter never shows 0, even a dummy load. 73 N4BFD http://www.qrz.com/db/N4BFD On Fri, Dec 11, 2009 at 6:48 AM, roger g6...@tiscali.co.uk wrote: I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? Roger G0IUW ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to n4b...@gmail.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
On Fri, Dec 11, 2009 at 3:48 AM, roger g6...@tiscali.co.uk wrote: I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? It is actually correct. It has to do with S9 being 50uV into a 50ohm load and each S-unit below that being a 6dB reduction in signal (voltage cut in half). At some point the noise voltage dominates and that is where the S-meter will sit. That the S-meter drops when you turn on the preamp tells you that the preamp is doing its job as the effective noise floor is reduced. While this may bother you what it is telling you is that your radio is actually a calibrated RF power measuring instrument. S-meter readings actually mean something with the Flex radios. -- 73 de Brian, WB6RQN/J79BPL ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
It also depends on the RX bandwidth.. Shrink the bandwidth to 10 hz and the S-meter will read less. Exactly what it should. 73, Dudley WA5QPZ Brian Lloyd wrote: On Fri, Dec 11, 2009 at 3:48 AM, roger g6...@tiscali.co.uk wrote: I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? It is actually correct. It has to do with S9 being 50uV into a 50ohm load and each S-unit below that being a 6dB reduction in signal (voltage cut in half). At some point the noise voltage dominates and that is where the S-meter will sit. That the S-meter drops when you turn on the preamp tells you that the preamp is doing its job as the effective noise floor is reduced. While this may bother you what it is telling you is that your radio is actually a calibrated RF power measuring instrument. S-meter readings actually mean something with the Flex radios. ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
Brian Lloyd wrote: On Fri, Dec 11, 2009 at 3:48 AM, roger g6...@tiscali.co.uk wrote: I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? It is actually correct. It has to do with S9 being 50uV into a 50ohm load and each S-unit below that being a 6dB reduction in signal (voltage cut in half). At some point the noise voltage dominates and that is where the S-meter will sit. That the S-meter drops when you turn on the preamp tells you that the preamp is doing its job as the effective noise floor is reduced. While this may bother you what it is telling you is that your radio is actually a calibrated RF power measuring instrument. S-meter readings actually mean something with the Flex radios. What Brian says is accurate, however there are a couple of wrinkles regarding the original question. On the FLEX 3000 there is only 1 preamp setting, so I have Pre, Off or Att. There is no pre1 and pre2. Also I don't see why the meter reading would drop when selecting Att. On my F3K, on 75m to a dummy load with 2,7k BW, my S-reading is S3 in the Off setting. With the Preamp on it drops to ~S1. With Att engaged it rises to ~S5. This is just what I would expect. As Brian says, this may be counterintuitive for folks used to the 'old' way of doing things, but it is fundamentally correct. 73 Alf NU8I Scottsdale AZ DM43an ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
You are not using the most current version of PowerSDR. There are in fact two preamp settings (pre1 pre2) along with a preamp ECO change provided by FlexRadio Systems to support the software change for radios manufactured before Sept 2009. -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Alfred Green Sent: Friday, December 11, 2009 3:30 PM To: Brian Lloyd Cc: flexradio@flex-radio.biz; roger Subject: Re: [Flexradio] Flex 3000 Signal meter Brian Lloyd wrote: On Fri, Dec 11, 2009 at 3:48 AM, roger g6...@tiscali.co.uk wrote: I have noticed that with the RX preamps set to OFF, the Signal meter reads a steady S3 with the antenna disconnected. With Pre1, Pre2 or Att selected, the meter reads 0 Is this normal? or have I set something incorrctly or misunderstood something? It is actually correct. It has to do with S9 being 50uV into a 50ohm load and each S-unit below that being a 6dB reduction in signal (voltage cut in half). At some point the noise voltage dominates and that is where the S-meter will sit. That the S-meter drops when you turn on the preamp tells you that the preamp is doing its job as the effective noise floor is reduced. While this may bother you what it is telling you is that your radio is actually a calibrated RF power measuring instrument. S-meter readings actually mean something with the Flex radios. What Brian says is accurate, however there are a couple of wrinkles regarding the original question. On the FLEX 3000 there is only 1 preamp setting, so I have Pre, Off or Att. There is no pre1 and pre2. Also I don't see why the meter reading would drop when selecting Att. On my F3K, on 75m to a dummy load with 2,7k BW, my S-reading is S3 in the Off setting. With the Preamp on it drops to ~S1. With Att engaged it rises to ~S5. This is just what I would expect. As Brian says, this may be counterintuitive for folks used to the 'old' way of doing things, but it is fundamentally correct. 73 Alf NU8I Scottsdale AZ DM43an ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to telli...@itsco.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
Re: [Flexradio] Flex 3000 Signal meter
Tim Ellison wrote: You are not using the most current version of PowerSDR. There are in fact two preamp settings (pre1 pre2) along with a preamp ECO change provided by FlexRadio Systems to support the software change for radios manufactured before Sept 2009. Hey Tim, You are correct, I'm still at 1.18.2 on my F3K machine. I haven't had the upgrade done yet, so I presume that going to 18.3 wouldn't buy me anything anyway. I didn't realize that there was extra functionality being added to the pre-amp, I was under the impression it was just for dynamic range issues. I'll get it done early in the New Year, and I realize it will cost me more but I can't face shipping it, and being without it over the Holidays. Having said all that, there is still the anomaly from the OP where the S-meter dropped when selecting ATT. That's not what I see, nor would expect. 73 Alf NU8I Scottsdale AZ DM43an ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to arch...@mail-archive.com
