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K3 VFO B Anomaly

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Robert Beard

K3 VFO B Anomaly

Good Morning List,

Just noticed, while tuning VFO A down through 4.800.0 MHz, I can hear a relay switching.
I believe this is band pass filter switching on the KBPF3 board.

All well and good, except that VFO B jumps to 3.526.76 MHz at the switching point, regardless of any previous setting.

When tuning VFO A back up through 4.8 MHz., the relay switches and VFO B jumps to 5.300.00 MHz.

Anyone else seeing this curious behavior? (Or am I missing something....?)

K3 is s/n 1500 with 3.14/2.16/2.16 installed.

Best regards,

Rob, N6VX
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Paul Franson-2

Re: K3 VFO B Anomaly

I see similar strange things when tuning VFO A around 4.800. When VFO A
is below 4.800 B is at 4799.96 - when A goes above 4.800 B goes to 5.285
MHz. This is on SN 1114 - 3.25

Glad I don't normally listen there.

Paul W2LE

Robert Beard wrote:

> Good Morning List,
>
> Just noticed, while tuning VFO A down through 4.800.0 MHz, I can hear a relay switching.
> I believe this is band pass filter switching on the KBPF3 board.
>
> All well and good, except that VFO B jumps to 3.526.76 MHz at the switching point, regardless of any previous setting.
>
> When tuning VFO A back up through 4.8 MHz., the relay switches and VFO B jumps to 5.300.00 MHz.
>
> Anyone else seeing this curious behavior? (Or am I missing something....?)
>
> K3 is s/n 1500 with 3.14/2.16/2.16 installed.
>
> Best regards,
>
> Rob, N6VX
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

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allenrw1955

Re: K3 VFO B Anomaly

W2LE wrote:
My K3 does the same thing tuning VFO A or B at 4800, probably you can't
have separate bandpass filters on the VFOs so the other frequency has to
change.
Bob
KB1FRW

> I see similar strange things when tuning VFO A around 4.800. When VFO A
> is below 4.800 B is at 4799.96 - when A goes above 4.800 B goes to 5.285
> MHz. This is on SN 1114 - 3.25
>
> Glad I don't normally listen there.
>
> Paul W2LE
>
> Robert Beard wrote:
>
>> Good Morning List,
>>
>> Just noticed, while tuning VFO A down through 4.800.0 MHz, I can hear a relay switching.
>> I believe this is band pass filter switching on the KBPF3 board.
>>
>> All well and good, except that VFO B jumps to 3.526.76 MHz at the switching point, regardless of any previous setting.
>>
>> When tuning VFO A back up through 4.8 MHz., the relay switches and VFO B jumps to 5.300.00 MHz.
>>
>> Anyone else seeing this curious behavior? (Or am I missing something....?)
>>
>> K3 is s/n 1500 with 3.14/2.16/2.16 installed.
>>
>> Best regards,
>>
>> Rob, N6VX
>> ______________________________________________________________
>>
>
>

allenrw1955

Re: K3 VFO B Anomaly

Just thought to check other frequencies. This does this several places
as you tune the radio through the frequencies.
Bob
KB1FRW

Bob W Allen wrote:

> W2LE wrote:
> My K3 does the same thing tuning VFO A or B at 4800, probably you can't
> have separate bandpass filters on the VFOs so the other frequency has to
> change.
> Bob
> KB1FRW
>
>
>
>> I see similar strange things when tuning VFO A around 4.800. When VFO A
>> is below 4.800 B is at 4799.96 - when A goes above 4.800 B goes to 5.285
>> MHz. This is on SN 1114 - 3.25
>>
>> Glad I don't normally listen there.
>>
>> Paul W2LE
>>
>> Robert Beard wrote:
>>
>>
>>> Good Morning List,
>>>
>>> Just noticed, while tuning VFO A down through 4.800.0 MHz, I can hear a relay switching.
>>> I believe this is band pass filter switching on the KBPF3 board.
>>>
>>> All well and good, except that VFO B jumps to 3.526.76 MHz at the switching point, regardless of any previous setting.
>>>
>>> When tuning VFO A back up through 4.8 MHz., the relay switches and VFO B jumps to 5.300.00 MHz.
>>>
>>> Anyone else seeing this curious behavior? (Or am I missing something....?)
>>>
>>> K3 is s/n 1500 with 3.14/2.16/2.16 installed.
>>>
>>> Best regards,
>>>
>>> Rob, N6VX
>>> ______________________________________________________________
>>>
>>>
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
>

Van W1WCG

Re: K3 VFO B Anomaly

I think this effect is simply due to changing from one band memory to
another at these cross-over points...

Van W1WCG

Bob W Allen wrote:

> Just thought to check other frequencies. This does this several places
> as you tune the radio through the frequencies.
> Bob
> KB1FRW
>
> Bob W Allen wrote:
>
>> W2LE wrote:
>> My K3 does the same thing tuning VFO A or B at 4800, probably you can't
>> have separate bandpass filters on the VFOs so the other frequency has to
>> change.
>> Bob
>> KB1FRW
>>
>>
>>
>>
>>> I see similar strange things when tuning VFO A around 4.800. When VFO A
>>> is below 4.800 B is at 4799.96 - when A goes above 4.800 B goes to 5.285
>>> MHz. This is on SN 1114 - 3.25
>>>
>>> Glad I don't normally listen there.
>>>
>>> Paul W2LE
>>>
>>> Robert Beard wrote:
>>>
>>>
>>>
>>>> Good Morning List,
>>>>
>>>> Just noticed, while tuning VFO A down through 4.800.0 MHz, I can hear a relay switching.
>>>> I believe this is band pass filter switching on the KBPF3 board.
>>>>
>>>> All well and good, except that VFO B jumps to 3.526.76 MHz at the switching point, regardless of any previous setting.
>>>>
>>>> When tuning VFO A back up through 4.8 MHz., the relay switches and VFO B jumps to 5.300.00 MHz.
>>>>
>>>> Anyone else seeing this curious behavior? (Or am I missing something....?)
>>>>
>>>> K3 is s/n 1500 with 3.14/2.16/2.16 installed.
>>>>
>>>> Best regards,
>>>>
>>>> Rob, N6VX
>>>> ______________________________________________________________
>>>>
>>>>
>>>>
>>>
>>>
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>>
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

Paul Franson-2

Re: K3 VFO B Anomaly

In reply to this post by allenrw1955

That makes sense, my second rcvr doesn't have a BPF3 - only the main
rcvr has it.

Bob W Allen wrote:

Don Wilhelm-4

Re: K3 VFO B Anomaly

In reply to this post by Paul Franson-2

Paul,

The VFOs are staying on the same "band".
If you want different behavior, set VFO IND on in the menu.

73,
Don W3FPR

W2LE wrote: