[Elecraft] K1 with a strange XFIL problem...

[Don Wilhelm]

Bruce,

There is nothing overtly associated with the selection of FL3 that 
*should* cause a lockup.  The way the bandwidth is controlled is to vary 
the voltage of the XFIL/TONE signal from the D/A converter - front panel 
U2 and apply it to the varactors connected to the filter crystals.

I suspect that you have a corrupt bit(s) in EEPROM. You will have to do 
all the VFO, SIG and other menu calibration steps, but you can try a 
Reset to Firmware Defaults - see page 57 of the K1 manual.

But then I see that you have tried that - so perhaps a new firmware IC 
is in order - that is just a guess, but the best firmware 
troubleshooting tool is substitution.  You could also try replacing 
Front Panel U2 and U3 along with U1.

73,
Don W3FPR

On 7/2/2012 5:36 PM, Bruce Beford wrote:
> OK, folks.
> Time to put on your thinking caps...
> I just purchased a used K1. Has NB, ATU and 4 band board, set for
> 7/10.1/14/21 MHz. All appears to be operating normally, except...
> When cycling through the crystal filter bandwidths from FL1-FL3, once FL3 is
> reached, all buttons become unresponsive. The VFO readout still works, but
> the MCU will not respond to any key presses. The filter does actually switch
> to the narrowest setting, based on the audio response. Cycling the power
> returns the rig to normal operation (on FL1), and all works fine again until
> trying to use FL3.
>
> About the only other anomaly I notice is what seems to be a louder pop in
> the speaker when switching in RIT or XIT than I remember from my last K1. I
> have not yet begun any troubleshooting (except for a full reset). Just
> thought I would poll the collective wisdom here before digging in. Actually,
> I'll be getting ready for Lobstercon over the next couple of days, so I
> don't know how much time I'll be able to commit until after the weekend.
>
> I'd appreciate any thoughts or ideas on this one.
> Thanks es 72/73,
> Bruce, N1RX
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>