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How much current?

It might be better to set up a teams meeting, how far behind are you in time, I am GMT

KR

Andrew

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On 27 Jan 2025, 22:42, at 22:42, "Tommy Wooten via " <kf4rwg=[email protected]> wrote:
>Andrew
>Yes the power supply amps does peak with the modulation.
>I do have a generator.? I have used it when setting tx gain and output
>power for vhf/uhf.
>
>Tommy
>
>
>On Mon, Jan 27, 2025 at 5:31?PM Andrew Lenton via <a=
>[email protected]> wrote:
>
>> Hi Tommy,
>>
>> Is it still drawing 20 amp from the power supply?
>>
>> When you are speak into the mic,? do you have an audio dig generator?
>>
>> KR
>>
>> Andrew
>>
>> ?Get BlueMail for Android ?
>>
>> On 27 Jan 2025, 22:09, at 22:09, "Tommy Wooten via "
><kf4rwg=
>> [email protected]> wrote:
>> >Andrew,
>> >I have done some more measurements as you recommended.? I removed
>the
>> >PA
>> >board and attached a connector to the output of L305 separated from
>the
>> >rx/tx relay and HPF.? I have attached photos of the input and output
>> >voltages set at 10M USB with voice into the microphone.? These
>voltages
>> >are
>> >much less than what you said they should be.? The problem must be up
>> >stream
>> >from the PA FETs.
>> >The oscilloscope was set at 50 millivolt per div in both photos.
>The
>> >voltage was lower at the output of L305.!?? But measured about 6
>watts
>> >on
>> >the external power meter into a dummy load.
>> >
>> >The vhf/uhf works well so the driver is working.
>> >
>> >Thanks for your help.
>> >Tommy
>> >
>> >
>> >
>> >On Sun, Jan 26, 2025 at 10:55?AM Andrew Lenton via <a=
>> >[email protected]> wrote:
>> >
>> >> This is a very hard radio to work on, as you cannot easily get to
>the
>> >PA
>> >> board the way it is mounted and soldered into the pa driver board
>> >>
>> >>
>> >>
>> >> I would remove the PA board, replace L305, for starters while it
>is
>> >out
>> >> you can inspect the components one by one.
>> >>
>> >>
>> >>
>> >> This unit does not lend itself to test and measurements, as all
>you
>> >can do
>> >> is prod the rear.
>> >>
>> >>
>> >>
>> >> All 12V HF PA stages have an impedance in the milli Ohms 0.4 to
>0.6
>> >ohms,
>> >> as it draws 20A, or so, the output transformer has to match 0.6
>Ohms
>> >to a
>> >> 50 Ohm, so it needs to step up the voltage.
>> >>
>> >>
>> >>
>> >> The problem is it would be nice to lift L306 and put your Watt
>meter
>> >in
>> >> there, but you have to rip the PA board out then put it back
>together
>> >to
>> >> make the measurement, so impractical
>> >>
>> >>
>> >>
>> >> To protect the PA the is a coupler to control power and to protect
>> >the PA
>> >> against hi SWR, however, if no power is getting past the coupler
>you
>> >will
>> >> have full power 24/7
>> >>
>> >>
>> >>
>> >> There could be a fault here:
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> But only you can trace, so measure i/p to L305, you will get a
>> >voltage,
>> >> the out put will be higher at 100 Watts 50 Ohm the voltage will be
>> >70.7V
>> >> RMS, so PTP on a scope 200V if you are not getting this on the O/P
>> >then
>> >> move back to the I/P you should get 13.8 V? to 40V PTP. I have one
>of
>> >these
>> >> in bits working before I box it back together I will make some
>> >measurements
>> >> and send back to you. as the PA in not loaded with 50 OHM, the
>> >voltage can
>> >> rise too high
>> >>
>> >> You need to set a voltage on Ref or FOR to knock the power back to
>a
>> >few
>> >> Watts then you can uses CW and safely trace you signal.
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> KR
>> >>
>> >>
>> >>
>> >> Andrew G8UUG
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> -----Original Message-----
>> >> From: [email protected] <[email protected]> On Behalf Of Andrew
>Lenton
>> >> Sent: 26 January 2025 10:00
>> >> To: [email protected]
>> >> Subject: Re: [ic7000] IC7000 no HF Transmit
>> >>
>> >>
>> >>
>> >> This is a very hard radio to work on, as you can not easily get to
>> >the PA
>> >> board the way it is soldered into the pa driver.
>> >>
>> >>
>> >>
>> >> I would remove the PA board, replace L305, for starters while it
>is
>> >out
>> >> you can inspect the components one by one.
>> >>
>> >>
>> >>
>> >> This unit does not lend itself to test and measurements, as all
>you
>> >can do
>> >> is prod the rear.
>> >>
>> >>
>> >>
>> >> All HF PA stages have an impedance in the mOhms .1 .2 ohms as
>> >thet6drsw
>> >> 20A, the out put transformer has to match .1 of an ohm to 50, so
>it
>> >needs
>> >> to step up the voltage.
>> >>
>> >>
>> >>
>> >> KR
>> >>
>> >>
>> >>
>> >> Andrew
>> >>
>> >>
>> >>
>> >> I have a wiring unit, I can make some measurements for you
>> >>
>> >>
>> >>
>> >> ?Get BlueMail for Android ?
>> >>
>> >>
>> >>
>> >> On 26 Jan 2025, 01:32, at 01:32, "Tommy Wooten via " <
>> >> kf4rwg=[email protected]> wrote:
>> >>
>> >> >Bob, Thanks for the encouragement
>> >>
>> >> >
>> >>
>> >> >I have considered all of the suggestions for troubleshooting the
>> >>
>> >> >problem I have with the IC7000.? I have tried to trace the HF RF
>> >path
>> >>
>> >> >with an oscilloscope from where the signal comes through the
>cable
>> >from
>> >>
>> >> >the main board to the PA board.? I have traced the signal and
>> >inspect
>> >>
>> >> >all components through to the output at ant1.? The signal seems
>to
>> >>
>> >> >loose its punch where the PA FETs combine into the L305
>transformer.
>> >>
>> >> >The bias setting of the PA FETs seem to be correct.? After the
>> >signal
>> >>
>> >> >reaches the rx/rx relay it passes through the selected HPF where
>it
>> >>
>> >> >reaches ant1.? The resulting signal is only a few milliwatts.? I
>> >have
>> >>
>> >> >tried to keep the setting in SSB and I see modulation when
>speaking
>> >>
>> >> >into the microphone.
>> >>
>> >> >I know it is difficult to troubleshoot the issue remotely but I
>> >>
>> >> >appreciate any and all ideas.
>> >>
>> >> >Thanks
>> >>
>> >> >Tommy. KF4RWG
>> >>
>> >> >
>> >>
>> >> >
>> >>
>> >> >
>> >>
>> >> >On Sat, Jan 25, 2025 at 6:31?PM Bob via <W4JFABob=
>> >>
>> >> >[email protected]> wrote:
>> >>
>> >> >
>> >>
>> >> >> Well this is #30 then. That's OK because when the rest of us
>have
>> >>
>> >> >this
>> >>
>> >> >> problem we'll appreciate every one of these replies.
>> >>
>> >> >> Keep on writin' you guys.
>> >>
>> >> >> Bob W4JFA
>> >>
>> >> >>
>> >>
>> >> >> On Thu, Jan 23, 2025 at 4:40?PM Geoff via <vk3zgw=
>> >>
>> >> >> [email protected]> wrote:
>> >>
>> >> >>
>> >>
>> >> >>> Forgive me if this has been mentioned before but as this is
>the
>> >29th
>> >>
>> >> >>> reply I haven't gone back and read everything.
>> >>
>> >> >>>
>> >>
>> >> >>> I always go first to where the effect of a fault is obvious
>> >without
>> >>
>> >> >any
>> >>
>> >> >>> ambiguity, in this case the rf output ie Ant 1 connector,
>working
>> >>
>> >> >back to
>> >>
>> >> >>> eliminate ALL the stages involved, including in this case the
>> >SO32
>> >>
>> >> >jack.
>> >>
>> >> >>>
>> >>
>> >> >>> Good luck.
>> >>
>> >> >>>
>> >>
>> >> >>> Geoff
>> >>
>> >> >>> VK3ZGW
>> >>
>> >> >>>
>> >>
>> >> >>>
>> >>
>> >> >>
>> >>
>> >> >>
>> >>
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>> >>
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>> >>
>> >> >
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