[Elecraft] K3 - No RF output

[Wes]

On 6/15/2020 1:10 AM, Dick Dievendorff wrote:
> Is TX test on?
>
> 73 de Dick, K6KR
>
>> On Jun 15, 2020, at 01:06, G4BVH <g4bvh at cathyandpeter.com> wrote:
>>
>> Hi,
>>
>>
>>
>> I have had a fault develop on my K3 whereby there is no RF being produced. I
>> have emailed the details to Elecraft support and am hoping to receive a
>> reply with suggestions. However, I thought I would also send the details
>> here in case anyone can suggest something to try or investigate further.
>>
>>
>>
>> I have a K3, serial number 6482 which I built from a kit. It has worked
>> flawlessly since I built it. I have the 400Hz and 2.7kHz (2.8kHz?) filters
>> fitted and the 100W module but no other additions.
>>
>>
>>
>> A few days ago, it was running 20W of FT8 and I suddenly discovered that it
>> hadn't been transmitting. Everything appeared that it should be
>> transmitting: the red TX LED was lit,_it was not in TEST mode (TX not flashing)_  but there was no RF output displayed on the bar graph and
>> definitely nothing coming out on any mode. There is no RF if I wind down the
>> power below the 10W level, there is the usual relay click going through 12W
>> - 13W and still no RF above this level, ie on towards 100W.
>>
>>
>>
>> The K3 metering shows 13.5V and 0.84 on receive, 0.97A on the lower power
>> level setting and 1.18A on the higher power setting on transmit. The RF
>> output bar graph always displays 1 bar on transmit no matter what the power
>> level  is set but there is no RF coming out.
>>
>>
>>
>> I tried the TX calibration but it fails saying the power level didn't reach
>> that required.
>>
>>
>>
>> The receiver works fine and I can hear the CW side tone and SSB, AM and FM
>> audio monitoring as normal.
>>
>>
>>
>> I have removed and reseated the front panel and also the 3 coax patch leads
>> behind the front panel but this made no difference. There is a yellow LED,
>> D33, on the main board which is lit on receive and goes out on transmit.
>>
>>
>>
>> The latest firmware is installed - I updated this a month or so ago.
>>
>>
>>
>> TX inhibit is OFF and the 20A breaker has not tripped.
>>
>>
>>
>> Any thoughts or suggestions gratefully received.
>>
>>
>>
>> Very many thanks and 73,
>>
>>
>>
>> Peter, G4BVH
>>
>>
>>
>>