http://elecraft.85.s1.nabble.com/Re-KB1VBF-Re-K2-Hi-Current-still-tp7303283p7343298.html
I didn't seem to get much of anything on J7 pin 10. (is this the same as P1
> Brian,
>
> The KDSP2 is not likely the cause of the problem.
>
> Your 3.53 volts on D9 is within the range of sanity for 12 to9 15 watts
> output.
> The fact that the K2 display indicates P 1.0 says that voltage is not
> making it back to the MCU - or that the MCU has a damaged input at pin 2.
>
> The voltage at the cathode of D9 should be carried through R66 (check
> both ends), and from there go to the connector J7 pin 10. From that
> point, it will go to Control Board P2 pin 12, and then to CB P4 pin 10 -
> then on to CB R12 and finally to CB U6 pin 2.
>
> Check all those places for good soldering, and then check to see if the
> DC voltage during a TUNE at the RF Board D9 cathode equals the DC
> voltage at Control Board U6 pin 2. If it does, then CB U6 has a damaged
> input pin. If the voltages between D9 cathode and CB U6 pin 2 are
> substantially different, then there is a bad connection somewhere in the
> path between those two points.
>
> It is not unusual for a bad solder connection to take some time to cause
> problems - it will conduct just fine due to the mechanical connection
> until oxidation creates additional resistance in the path and thus a
> failure.
>
> If solder connection oxidation is not the problem, then the MCU IC could
> have been damaged by static during assembly. Such damage may not be
> immediate, but will drastically reduce the life of integrated circuits.
>
> 73,
> Don W3FPR
>
> On 2/20/2012 9:40 PM,
[hidden email] wrote:
>>
>> Gary and Don:
>>
>> No KAT2 installed: (I am building it but have not finished it yet)
>>
>> There is about 3.53 volts on D9 when TUNE is pressed, 0 volts
>> otherwise. I set the power level to 15 watts but, as I said before,
>> roughly 20 watts comes out no matter what I set the power to, and the
>> HI CUR warning is always there with "P 1.0" power indicated.
>>
>> Do I check the MCU next? Is that on the Control Board? Could the
>> KDSP2 board be causing a problem?
>>
>> Thanks again guys!
>>
>> Brian KB1VBF
>>
>> ------------------------------------------------------------------------
>>
>> *From: *"Gary Surrency" <
[hidden email]>
>> *To: *"b denley" <
[hidden email]>
>> *Sent: *Monday, February 20, 2012 3:05:13 PM
>> *Subject: *KB1VBF Re: [Elecraft] [K2] Hi Current...still
>>
>> Don't connect a KAT2, KAT100, or KPA100 until the power control
>> problem is fixed, since any of those can have damage that affects the
>> power control.
>>
>> Damage to D9 on the RF board or to the VRFDET input pin 2 of the
>> 18C452 MCU can cause a loss of power control too. If OK, there should
>> be up to about 4VDC at the cathode of D9 when transmitting at full
>> power (14-15 watts).
>>
>>
>> --
>> 73, Gary AB7MY
>>
>> =========
>>
[hidden email]
>> Elecraft Technical Support
>>
>>
>> On 2/20/2012 11:58 AM,
[hidden email] wrote:
>>
>> Thanks Gary. The rig does put out power as it turns out (plenty
>> in fact) but is not controlling that power. High power comes out
>> at any power setting with the associated Hi Cur warning. See Don
>> Wilhelm's latest advice below.
>>
>> Brian KB1VBF
>>
>> ------------------------------------------------------------------------
>>
>> *From: *"Gary Surrency" <
[hidden email]>
>> *To: *
[hidden email]
>> *Cc: *"Don Wilhelm" <
[hidden email]>, "b denley"
>> <
[hidden email]>, "Wayne Burdick" <
[hidden email]>,
>> "
[hidden email] Wilhelm" <
[hidden email]>
>> *Sent: *Monday, February 20, 2012 1:20:22 PM
>> *Subject: *KB1VBF Re: [Elecraft] [K2] Hi Current...still
>>
>> Try all bands.
>>
>> Make sure no relays have a soldering iron burn.
>>
>> Check the t-r switch has no reversed diodes or Q2 is reversed. The
>> pictorial in the back of the manual shows which way these parts go.
>>
>> An open RFC6 will cause self oscillation. This part is under Q6 on
>> the bottom of the RF board.
>>
>> Check all parts are correct in the Q5-Q8 area.
>>
>> Check D9's cathode has about 4VDC at 14-15w if the rig will
>> produce that power level.
>>
>> Check the BNC connector does not have a broken ground pin. I have
>> seen that before.
>>
>> --
>> 73, Gary AB7MY
>>
>> =========
>>
[hidden email]
>> Elecraft Technical Support
>>
>>
>>
>> On 2/18/2012 10:33 PM, Don Wilhelm wrote:
>>
>> Brian,
>>
>> Is this condition on one band, or does it exist on all bands?
>>
>> The winding of T4 will affect all bands,
>> A Low Pass Filter problem will affect one or two bands.
>>
>> Transmit into a 50 ohm dummy load - then:
>> Quickly measure the voltage at the base of Q7 or Q8 during a
>> TUNE. It should be between 0.60 and 0.64 volts.
>>
>> Count the turns on T4 carefully, the green winding should have
>> 2 turns and the white winding should have 3 turns. The "link"
>> wires should go from the front of the transformer directly to
>> the back (they do not wrap through both holes)..
>>
>> 73,
>> Don W3FPR
>>
>> On 2/18/2012 10:15 PM, Wayne Burdick wrote:
>>
>> Did you check the winding on the PA transformer? If the
>> impedance were much too low, the current could be too
>> high. Could also be excessive bias current. What's the
>> current drain in transmit mode, key up (i.e. tapping XMIT
>> but not the key)?
>>
>> Wayne
>> N6KR
>>
>> On Feb 18, 2012, at 7:09 PM,
[hidden email] wrote:
>>
>>
>>
>> After getting the HiCur message, I replaced the two PA
>> transistors, the associated hardware, Q11 and Q13, and
>> R50. Unfortunately I stll get the same message:
>> HiCur when I press TUNE with power any higher than
>> about 1.5 watts inot a 50 ohm dummy load. Any have
>> any ideas about what else might cause this problem?
>>
>>
>>
>> Brian KB1VBF
>>
>>
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