Loading ...
Sorry, an error occurred while loading the content.

Good news, then not so good...

Expand Messages
  • Mike
    The good news is that I got my RXTX6.3 main board kit! I assembled it, and made up the 80/40 receive filter. I had the 80/40 PA/Filter completed earlier.
    Message 1 of 6 , Feb 27, 2009
    • 0 Attachment
      The good news is that I got my RXTX6.3 main board kit!
      I assembled it, and made up the 80/40 receive filter.
      I had the 80/40 PA/Filter completed earlier.

      Having no sound card in the HP computer running Vista, I attached a
      cable to the I/Q outputs of the RXTX, and applied this to the PC's
      front panel LINE IN.

      Initially, I saw only a lot of NOISE on the panoramic display, running
      PowerSDR. (This was well over S-9. It would drop to about S-9 when I
      shorted the antenna terminals out.)

      I attached an antenna, and could see and hear CW stations in the area
      of 3.546 Mhz, as anticipated.

      My current draw was about 90 Ma. I let it run all night, with no
      antenna attached.

      This morning, I saw that the current draw was about 162 ma!
      The current draw made no change, when I removed both of the plug-in
      cards on the RXTX main board. (It was always in RECEIVE mode.)

      Looking at the display in PowerSDR, the noise is gone. (!!) I see a
      meter reading of about S-2, maybe.

      I have inspected the unit, looking for bridges, etc. It "looks"
      clean. (It did run all day on Friday, I will add... It did work, but
      had such a terribly high noise floor, that only the very strongest
      stations were heard.)

      I have given the unit a short look, mainly because my knowledge of
      this unit is so very low. I will list my limited findings:

      I experimented with momentarily applying a HIGH to the PTT-I point,
      through a 470 Ohm resistor, fed by +12 Volts, I see the following changes:
      PTT-I goes from 0 to 9.6 volts
      S12V goes from 0 to 9 volts
      PTT-O goes from 4.25 to 0 volts
      The current rises from 162 to 238 ma

      If I remove the two plug-in cards, the current actually DROPS when I
      apply the logic HIGH with the 470 Ohm resistor, as follows!
      The current goes from 162 to 150 ma.

      The QSA and QSD clocks look as if they are OK. (I see very robust
      signals with my scope.) No change is noted.

      I used to see positive signals on the receive outputs to the sound
      card, now the signal is very subtle. Observing PowerSDR, there is
      POSSIBLY a signal being displayed, but the trace is mostly off the
      lower part of the display.

      My main points:
      1. I had a very HIGH background noise level, with no or shorted antenna
      2. The current draw was about 90 Ma
      4. The radio appeared to work, otherwise, if I ties an antenna to it
      5. Now, I have a very LOW background noise level, but the current is
      612 Ma in receive mode.
      6. The radio MAY be working, but is largely deaf
      7. I have NOT applied transmit I/Q
      8. I had gone to transmit MODE for the first time.this afternoon; This
      was for under 2 seconds, just to observe the current draw, as I had
      described above

      Where do I begin to look, good technicians?

      -Mike-
      K0JTA
    • Bill P.
      Something should be warm if the measurements are correct. Remove the PA module does the currant draw change? Check the PA heat sink and measure the voltage
      Message 2 of 6 , Feb 27, 2009
      • 0 Attachment
        Something should be warm if the measurements are correct. Remove the
        PA module does the currant draw change? Check the PA heat sink and
        measure the voltage drops across R210 & R211, the 2.1 ohm source
        resistors on each FET. Shoud be 55mv drop. Maybe one of the
        resistors shows higher drop therefore the FET associated FET is bad.

        If you want RX only without the PA, the PA pins for the antenna
        passthrough to the RX must be jumpered,,,,, from memory, I think it is
        pins 1 & 5.

        If the SR is still drawing high currant without the PA module, then it
        gets more difficult but suspect a solid state device internally
        shorting to ground if there are no circuit board shorts.

        80/40 are sometimes dead in the evening , listen for WWV on 2.5, 5 or
        10Mhz or put your commercial gear on low power and perform a transmission.

        Sometimes the Software does not start correctly or if USB there can be
        a problem, do a cold boot with all connections in place.

        Bill k6acj




        --- In softrock40@yahoogroups.com, "Mike" <mike@...> wrote:
        >
        > The good news is that I got my RXTX6.3 main board kit!
        > I assembled it, and made up the 80/40 receive filter.
        > I had the 80/40 PA/Filter completed earlier.
        >
        > Having no sound card in the HP computer running Vista, I attached a
        > cable to the I/Q outputs of the RXTX, and applied this to the PC's
        > front panel LINE IN.
        >
        > Initially, I saw only a lot of NOISE on the panoramic display, running
        > PowerSDR. (This was well over S-9. It would drop to about S-9 when I
        > shorted the antenna terminals out.)
        >
        > I attached an antenna, and could see and hear CW stations in the area
        > of 3.546 Mhz, as anticipated.
        >
        > My current draw was about 90 Ma. I let it run all night, with no
        > antenna attached.
        >
        > This morning, I saw that the current draw was about 162 ma!
        > The current draw made no change, when I removed both of the plug-in
        > cards on the RXTX main board. (It was always in RECEIVE mode.)
        >
        > Looking at the display in PowerSDR, the noise is gone. (!!) I see a
        > meter reading of about S-2, maybe.
        >
        > I have inspected the unit, looking for bridges, etc. It "looks"
        > clean. (It did run all day on Friday, I will add... It did work, but
        > had such a terribly high noise floor, that only the very strongest
        > stations were heard.)
        >
        > I have given the unit a short look, mainly because my knowledge of
        > this unit is so very low. I will list my limited findings:
        >
        > I experimented with momentarily applying a HIGH to the PTT-I point,
        > through a 470 Ohm resistor, fed by +12 Volts, I see the following
        changes:
        > PTT-I goes from 0 to 9.6 volts
        > S12V goes from 0 to 9 volts
        > PTT-O goes from 4.25 to 0 volts
        > The current rises from 162 to 238 ma
        >
        > If I remove the two plug-in cards, the current actually DROPS when I
        > apply the logic HIGH with the 470 Ohm resistor, as follows!
        > The current goes from 162 to 150 ma.
        >
        > The QSA and QSD clocks look as if they are OK. (I see very robust
        > signals with my scope.) No change is noted.
        >
        > I used to see positive signals on the receive outputs to the sound
        > card, now the signal is very subtle. Observing PowerSDR, there is
        > POSSIBLY a signal being displayed, but the trace is mostly off the
        > lower part of the display.
        >
        > My main points:
        > 1. I had a very HIGH background noise level, with no or shorted antenna
        > 2. The current draw was about 90 Ma
        > 4. The radio appeared to work, otherwise, if I ties an antenna to it
        > 5. Now, I have a very LOW background noise level, but the current is
        > 612 Ma in receive mode.
        > 6. The radio MAY be working, but is largely deaf
        > 7. I have NOT applied transmit I/Q
        > 8. I had gone to transmit MODE for the first time.this afternoon; This
        > was for under 2 seconds, just to observe the current draw, as I had
        > described above
        >
        > Where do I begin to look, good technicians?
        >
        > -Mike-
        > K0JTA
        >
      • g8voip
        Hi Mike, I would look at the S12V line, 9V sounds too low as there should only be the drop across D1 (0.6V) and Q2. Looks like something dragging it down? Have
        Message 3 of 6 , Feb 28, 2009
        • 0 Attachment
          Hi Mike,

          I would look at the S12V line, 9V sounds too low as there should only
          be the drop across D1 (0.6V) and Q2. Looks like something dragging it
          down?

          Have you measured the 12V input when you did that test in case your
          supply is being pulled down as well and distorting all the readings.

          73, Bob G8VOI


          --- In softrock40@yahoogroups.com, "Mike" <mike@...> wrote:
          >
          > The good news is that I got my RXTX6.3 main board kit!
          > I assembled it, and made up the 80/40 receive filter.
          > I had the 80/40 PA/Filter completed earlier.
          >
          > Having no sound card in the HP computer running Vista, I attached a
          > cable to the I/Q outputs of the RXTX, and applied this to the PC's
          > front panel LINE IN.
          >
          > Initially, I saw only a lot of NOISE on the panoramic display, running
          > PowerSDR. (This was well over S-9. It would drop to about S-9 when I
          > shorted the antenna terminals out.)
          >
          > I attached an antenna, and could see and hear CW stations in the area
          > of 3.546 Mhz, as anticipated.
          >
          > My current draw was about 90 Ma. I let it run all night, with no
          > antenna attached.
          >
          > This morning, I saw that the current draw was about 162 ma!
          > The current draw made no change, when I removed both of the plug-in
          > cards on the RXTX main board. (It was always in RECEIVE mode.)
          >
          > Looking at the display in PowerSDR, the noise is gone. (!!) I see a
          > meter reading of about S-2, maybe.
          >
          > I have inspected the unit, looking for bridges, etc. It "looks"
          > clean. (It did run all day on Friday, I will add... It did work, but
          > had such a terribly high noise floor, that only the very strongest
          > stations were heard.)
          >
          > I have given the unit a short look, mainly because my knowledge of
          > this unit is so very low. I will list my limited findings:
          >
          > I experimented with momentarily applying a HIGH to the PTT-I point,
          > through a 470 Ohm resistor, fed by +12 Volts, I see the following
          changes:
          > PTT-I goes from 0 to 9.6 volts
          > S12V goes from 0 to 9 volts
          > PTT-O goes from 4.25 to 0 volts
          > The current rises from 162 to 238 ma
          >
          > If I remove the two plug-in cards, the current actually DROPS when I
          > apply the logic HIGH with the 470 Ohm resistor, as follows!
          > The current goes from 162 to 150 ma.
          >
          > The QSA and QSD clocks look as if they are OK. (I see very robust
          > signals with my scope.) No change is noted.
          >
          > I used to see positive signals on the receive outputs to the sound
          > card, now the signal is very subtle. Observing PowerSDR, there is
          > POSSIBLY a signal being displayed, but the trace is mostly off the
          > lower part of the display.
          >
          > My main points:
          > 1. I had a very HIGH background noise level, with no or shorted antenna
          > 2. The current draw was about 90 Ma
          > 4. The radio appeared to work, otherwise, if I ties an antenna to it
          > 5. Now, I have a very LOW background noise level, but the current is
          > 612 Ma in receive mode.
          > 6. The radio MAY be working, but is largely deaf
          > 7. I have NOT applied transmit I/Q
          > 8. I had gone to transmit MODE for the first time.this afternoon; This
          > was for under 2 seconds, just to observe the current draw, as I had
          > described above
          >
          > Where do I begin to look, good technicians?
          >
          > -Mike-
          > K0JTA
          >
        • Mike
          ... Hi, Bob; I had made only a quick test, so my earlier figures were skewed by my initial about 12 volts supply voltage. I set the DC supply to 13.0 Volts.
          Message 4 of 6 , Feb 28, 2009
          • 0 Attachment
            --- In softrock40@yahoogroups.com, "g8voip" <g8voi.reeves59@...> wrote:
            >
            > Hi Mike,
            >
            > I would look at the S12V line, 9V sounds too low as there should only
            > be the drop across D1 (0.6V) and Q2. Looks like something dragging it
            > down?

            Hi, Bob;
            I had made only a quick test, so my earlier figures were skewed by my
            initial "about 12 volts" supply voltage.
            I set the DC supply to 13.0 Volts.
            The S12 goes from 0 Volts in receive to 12.26 Volts in PTT


            >
            > Have you measured the 12V input when you did that test in case your
            > supply is being pulled down as well and distorting all the readings.

            I checked: The Astron supply is not being dragged down.
            The current draw is 161 Ma in receive.
            The current draw drops to about 150 Ma in transmit mode.
            BOTH of the plug-in filter-PA cards are NOT INSTALLED.
            The receive current draw does NOT change if the two cards are installed.
            -Mike- K0JTA
          • Mike
            ... The normal current draw -was- 90 Ma; It is now 160 Ma. (Not too much current...) Remove the ... No added current is being drawn by the PA/Filter. (The 160
            Message 5 of 6 , Feb 28, 2009
            • 0 Attachment
              --- In softrock40@yahoogroups.com, "Bill P." <k6acj@...> wrote:
              >
              > Something should be warm if the measurements are correct.

              The normal current draw -was- 90 Ma; It is now 160 Ma. (Not too much
              current...)

              Remove the
              > PA module does the currant draw change? Check the PA heat sink and
              > measure the voltage drops across R210 & R211, the 2.1 ohm source
              > resistors on each FET. Shoud be 55mv drop. Maybe one of the
              > resistors shows higher drop therefore the FET associated FET is bad.

              No added current is being drawn by the PA/Filter.
              (The 160 Ma current draw remains the same, no matter if the receive
              bandpass filters or if the PA/Filter boards are installed or not.


              >
              > If the SR is still drawing high currant without the PA module, then it
              > gets more difficult but suspect a solid state device internally
              > shorting to ground if there are no circuit board shorts.

              This is what I am afraid of...

              A bit of history:
              - The unit initially drew about 90 Ma in receive.
              - It now draws about 160 Ma in receive.
              - The PA/Filter and the receive bandpass boards are NOT installed.
              - I have never tried to transmit, yet.
              - The normal QSD and QSE signals are still present on the board.
              Using PowerSDR, the NOISE FLOOR was really, REALLY high!
              - The noise floor was well above S-9, even if the antenna inputs were
              shorted together.
              - The unit DID work at first. (For several hours.)
              - When the unit did work, BOTH of the PA/filter boards were installd.
              - The unit did receive, but it took a very BIG (S-9 + 10 to 20 dB) signal!
              - I had a good I/Q output from the RXTX output to the computer, when
              it worked.
              - I no longer have the I/Q output, and PowerSDR is showing a very LOW
              level in the panoramic adapter.


              >
              > 80/40 are sometimes dead in the evening , listen for WWV on 2.5, 5 or
              > 10Mhz or put your commercial gear on low power and perform a
              transmission.

              If I attach an antenna, I hear (and SEE) nothing.
              If I inject a signal from my service monitor, I hear (and see) nothing.


              >
              > Sometimes the Software does not start correctly or if USB there can be
              > a problem, do a cold boot with all connections in place.

              No USB is being used at this time. I have only POWER, ANTENNA and the
              I/Q wires attached to the RXTX.

              Major question: Dare I use a DVM to look for shorts? Or, will this
              do damage to the ICs that are in place?????

              Related question: How do I locate the short or added load? (To
              resolve the issue.)

              Thank you! -Mike- K0JTA
            • Bill P.
              Yes, around 90ma draw on receive is about right. It would be very hard to help at this point, leave the power on and try to find a warm part. After that it
              Message 6 of 6 , Feb 28, 2009
              • 0 Attachment
                Yes, around 90ma draw on receive is about right. It would be very
                hard to help at this point, leave the power on and try to find a warm
                part. After that it takes some real problem solving techniques that
                are hard to cover here.

                I just finished 2 hours of contacts making the board not-cold to
                touch, nothing on the bottom is warm, only the top area around R19 and
                the PTT and serial area are slightly warm. Bill k6acj



                --- In softrock40@yahoogroups.com, "Mike" <mike@...> wrote:
                >
                > --- In softrock40@yahoogroups.com, "Bill P." <k6acj@> wrote:
                > >
                > > Something should be warm if the measurements are correct.
                >
                > The normal current draw -was- 90 Ma; It is now 160 Ma. (Not too much
                > current...)
                >
                > Remove the
                > > PA module does the currant draw change? Check the PA heat sink and
                > > measure the voltage drops across R210 & R211, the 2.1 ohm source
                > > resistors on each FET. Shoud be 55mv drop. Maybe one of the
                > > resistors shows higher drop therefore the FET associated FET is bad.
                >
                > No added current is being drawn by the PA/Filter.
                > (The 160 Ma current draw remains the same, no matter if the receive
                > bandpass filters or if the PA/Filter boards are installed or not.
                >
                >
                > >
                > > If the SR is still drawing high currant without the PA module, then it
                > > gets more difficult but suspect a solid state device internally
                > > shorting to ground if there are no circuit board shorts.
                >
                > This is what I am afraid of...
                >
                > A bit of history:
                > - The unit initially drew about 90 Ma in receive.
                > - It now draws about 160 Ma in receive.
                > - The PA/Filter and the receive bandpass boards are NOT installed.
                > - I have never tried to transmit, yet.
                > - The normal QSD and QSE signals are still present on the board.
                > Using PowerSDR, the NOISE FLOOR was really, REALLY high!
                > - The noise floor was well above S-9, even if the antenna inputs were
                > shorted together.
                > - The unit DID work at first. (For several hours.)
                > - When the unit did work, BOTH of the PA/filter boards were installd.
                > - The unit did receive, but it took a very BIG (S-9 + 10 to 20 dB)
                signal!
                > - I had a good I/Q output from the RXTX output to the computer, when
                > it worked.
                > - I no longer have the I/Q output, and PowerSDR is showing a very LOW
                > level in the panoramic adapter.
                >
                >
                > >
                > > 80/40 are sometimes dead in the evening , listen for WWV on 2.5, 5 or
                > > 10Mhz or put your commercial gear on low power and perform a
                > transmission.
                >
                > If I attach an antenna, I hear (and SEE) nothing.
                > If I inject a signal from my service monitor, I hear (and see) nothing.
                >
                >
                > >
                > > Sometimes the Software does not start correctly or if USB there can be
                > > a problem, do a cold boot with all connections in place.
                >
                > No USB is being used at this time. I have only POWER, ANTENNA and the
                > I/Q wires attached to the RXTX.
                >
                > Major question: Dare I use a DVM to look for shorts? Or, will this
                > do damage to the ICs that are in place?????
                >
                > Related question: How do I locate the short or added load? (To
                > resolve the issue.)
                >
                > Thank you! -Mike- K0JTA
                >
              Your message has been successfully submitted and would be delivered to recipients shortly.