[Elecraft] K3 Phones / Diversity Question

Fri Aug 3 18:04:14 EDT 2012

Here is a link to a very small broadband active receiving antenna. The 
entire antenna and associated source follower and emitter follower 
buffer amp will fit inside a 6" x 2" PVC pipe. Very clever and elegant 
design, and it works extremely well. I've built two of them, and this 
weekend will be hanging one of them from a PVC boom attached to the 
tower. In addition to being an exceptional broadband receive-only 
antenna, it also works very well as a noise-sense antenna in conjunction 
with the DX Engineering NCC-1 to eliminate periodic local powerline noise.

< http://www.radiopassioni.it/pdf/pa0rdt-Mini-Whip.PDF >

Other useful information:
< http://carconline.blogspot.com/2009/05/pa0rdt-active-antenna.html >

73, Dale
WA8SRA

On 8/3/2012 2:32 PM, N5GE wrote:
> The diversity receive antenna (DRA) must be connected to the AUX antenna on the
> back of the K3.  Unless your DRA has the same gain as the transmit antenna you
> will need to use a Preamp on the DRA.
>
> I use a DRA that is a 38 inch diameter loop of aluminum tubing that I can rotate
> to peak up the signal of the far off station.  That loop has a 35 dB LNA
> attached.
>
> Most of us don't have the space to erect a large receive only, so we use smaller
> antennae for the DRA.  If you are one who has the property to make a full size
> DRA, then you can probably get by without a Preamp unless you locate the DRA as
> far away from the TX antenna as possible.  The old ship to shore stations used
> to locate the DRA and RX antennas miles from the transmitter, so since most of
> us can't do that, here are some links to specialized RX antennas.
>
> http://www.pixelsatradio.com/product/shortwave-magnetic-loop-antenna/
>
> http://www.dxengineering.com/search/department/antennas/brand/dx-engineering/part-type/hf-receive-antennas
>
> Don't let this discourage you.  The antenna I use is the one from PixelSat
> Radio, but you can make one just like it yourself if you like to build things.
>
> Amateur Radio Operator N5GE
> ARRL Lifetime Member
> QCWA Lifetime Member
>
> On Fri, 03 Aug 2012 10:16:18 -0700, Jim Bennett <w6jhb at mac.com> wrote:
>
>> Still have issues with this. Here are the settings in Config that I'm assuming are relevant:
>>
>> L-Mix-R = A  b
>> SPKRS = 1
>> SPKR + Ph = no
>> SQ Main = Sub Pot
>> SQ Sub = Sub Pot
>> Sub AF = Nor
>>
>> With these Config settings, the K3 works fine with the SubRX turned off; equal Main audio in both headphones. When I turn on the SubRX, it is still OK; I get Main audio in the left ear and Sub audio in the right ear. I know I'm getting the Sub audio in the right ear, as I can turn the sub VFO and hear the frequency change in my right ear. BUT, as soon as I turn on Diversity, I get almost no signal in the right ear. It isn't silent - it's just that the signal that is pounding in on the Main is nearly inaudible on the Sub. If the signal being received on the Main is less than S7, I can't even hear it on the Sub with Diversity turned on. If it is an S9 or greater signal, then I can just barely hear it on the Sub when Diversity is turned on.
>>
>> Very strange. The SubRX works fine until Diversity mode is enabled.
>>
>> Any ideas? Does this need to be escalated to Elecraft Tech Support?
>>
>>
>> On   Friday, Aug 3, 2012, at  Friday, 6:02 AM, Mike K2MK wrote:
>>
>>> Hi Jim,
>>>
>>> One of the following might be helpful.
>>>
>>> If you have CONFIG:SPKRS set to 1 and CONFIG:SPKR+PH set to YES it will turn
>>> off the right channel of your headphones. Avoid the problem by turning
>>> CONFIG:SPKR+PH to no when using diversity.
>>>
>>> You also need to consider the setting of two other parameters which can be
>>> confusing with respect to SUB RX use. The first is CONFIG:SUB AF. Depending
>>> on whether you have chosen BALANCE or NOR it changes the way the concentric
>>> audio control operates. The second is CONFIG:L-MIX-R which controls which
>>> receiver's audio is in which ear. This control gets overridden when
>>> diversity is used and reverts to MAIN in left ear and SUB in right ear. So
>>> you might have one arrangement set for general SUB RX use and when you go to
>>> diversity it changes.
>>>
>>> 73,
>>> Mike K2MK
>>>
>>>
>>>
>>> Jim Bennett wrote
>>>> I just recently added the sub receiver to my K3. I've been using the Sub
>>>> receiver (without diversity turned on) and all was fine. I have the Yamaha
>>>> CM500 headset - one cable plugged into the Phones jack and the other going
>>>> to the Mic jack. I also have an Icom SP-20 external speaker, and it's
>>>> connected to the Spkrs jack.
>>>>
>>>> Well, I engaged Diversity mode and at first thought it was working
>>>> properly. But, when I turned the AF to zero on the Main receiver, I
>>>> realized that the audio on the Sub was almost nonexistent signals are
>>>> there, but really, really weak. OK, so looking at the Config parameters, I
>>>> noticed in the KRX3 manual that SPKRS should be set to 1. Mine was set to
>>>> 2. I changed it to one and now have zero audio coming from the Sub
>>>> receiver. Not exactly what I was hoping for.
>>>>
>>>> What do I need to do to get my headphone audio in Diversity mode to act as
>>>> it does with the Sub turned on, but Diversity off?
>>>>
>>>> Confused, I am.
>>>>
>>>> Jim / W6JHB
>>>>
>>>
>>>
>>>
>>> --
>>> View this message in context: http://elecraft.365791.n2.nabble.com/K3-Phones-Diversity-Question-tp7560223p7560229.html
>>> Sent from the Elecraft mailing list archive at Nabble.com.
>>> ______________________________________________________________
>>> 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
>> ______________________________________________________________
>> 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
> ______________________________________________________________
> 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
>