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K3: Receive Ant Question

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K4FJ

K3: Receive Ant Question

Am I correct in assuming that the Rec Ant input is disconnected from the main receiver input upon transmit by way of a relay? If so, can I further assume that connecting a beverage, or other receive antenna, to the Receive Ant input will cause no harm to the main receiver upon transmit? In other words, is a relay enough protection?

I ask because I would like to rule out needing an external protection device when using a beverage antenna. I run full legal power.

Thanks in advance.

73, Steve, K4FJ

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Don Wilhelm-4

Re: K3: Receive Ant Question

Steve,

The RX antenna input is protected by a Carrier Operated Relay. Other
than that, there is no relay to disconnect the RX input.
If your TX antenna is sufficiently separated from the RX antenna, there
is no problem.
How much is 'significant' is often a question, and the answer depends on
your particular antenna installation.
If you hear the COR relay operating, yours is not providing sufficient
isolation and you should look into an external device (likely a relay
will do) to disconnect the RX antenna during transmit.

73,
Don W3FPR

On 11/13/2013 4:20 PM, Steve, K4FJ wrote:
> Am I correct in assuming that the Rec Ant input is disconnected from the main receiver input upon transmit by way of a relay? If so, can I further assume that connecting a beverage, or other receive antenna, to the Receive Ant input will cause no harm to the main receiver upon transmit? In other words, is a relay enough protection?
>
> I ask because I would like to rule out needing an external protection device when using a beverage antenna. I run full legal power.
>
>

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NY6C

Re: K3: Receive Ant Question

I use this on the RX antenna:

http://www.arraysolutions.com/Products/as_rxfep.htm

...works great.

-Greg NY6C

On Nov 13, 2013, at 3:16 PM, Don Wilhelm <[hidden email]> wrote:

> Steve,
>
> The RX antenna input is protected by a Carrier Operated Relay. Other than that, there is no relay to disconnect the RX input.
> If your TX antenna is sufficiently separated from the RX antenna, there is no problem.
> How much is 'significant' is often a question, and the answer depends on your particular antenna installation.
> If you hear the COR relay operating, yours is not providing sufficient isolation and you should look into an external device (likely a relay will do) to disconnect the RX antenna during transmit.
>
> 73,
> Don W3FPR
>
> On 11/13/2013 4:20 PM, Steve, K4FJ wrote:
>> Am I correct in assuming that the Rec Ant input is disconnected from the main receiver input upon transmit by way of a relay? If so, can I further assume that connecting a beverage, or other receive antenna, to the Receive Ant input will cause no harm to the main receiver upon transmit? In other words, is a relay enough protection?
>>
>> I ask because I would like to rule out needing an external protection device when using a beverage antenna. I run full legal power.
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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> Please help support this email list: http://www.qsl.net/donate.html
>

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Mike K2MK

Re: K3: Receive Ant Question

In reply to this post by K4FJ

Hi Steve,

It is separated by a relay but that doesn't mean that you can't damage internal circuitry. If you hear relay clicking sounds while you are transmitting then you have tripped the protective COR (carrier-operated relay). If this occurs then you need to reducer power or separate your antennas more, and/or provide external protection.

The diagram on page 42 of the K3 manual illustrates the presence of the COR(s).

73,
Mike K2MK

K4FJ wrote

Am I correct in assuming that the Rec Ant input is disconnected from the main receiver input upon transmit by way of a relay? If so, can I further assume that connecting a beverage, or other receive antenna, to the Receive Ant input will cause no harm to the main receiver upon transmit? In other words, is a relay enough protection?

I ask because I would like to rule out needing an external protection device when using a beverage antenna. I run full legal power.

Thanks in advance.

73, Steve, K4FJ

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alsopb

Re: K3: Receive Ant Question

Guys,

I thought he said RX antenna input. The COR is on the aux ant input.
There is no COR on the RX antenna input (it's not needed, I think.)

73 de Brian/K3KO

On 11/13/2013 22:28, Mike K2MK wrote:

> Hi Steve,
>
> It is separated by a relay but that doesn't mean that you can't damage
> internal circuitry. If you hear relay clicking sounds while you are
> transmitting then you have tripped the protective COR (carrier-operated
> relay). If this occurs then you need to reducer power or separate your
> antennas more, and/or provide external protection.
>
> The diagram on page 42 of the K3 manual illustrates the presence of the
> COR(s).
>
> 73,
> Mike K2MK
>
>
>
> K4FJ wrote
>> Am I correct in assuming that the Rec Ant input is disconnected from the
>> main receiver input upon transmit by way of a relay? If so, can I further
>> assume that connecting a beverage, or other receive antenna, to the
>> Receive Ant input will cause no harm to the main receiver upon transmit?
>> In other words, is a relay enough protection?
>>
>> I ask because I would like to rule out needing an external protection
>> device when using a beverage antenna. I run full legal power.
>>
>> Thanks in advance.
>>
>> 73, Steve, K4FJ
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:
>
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>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
>
>
> --
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> Sent from the Elecraft mailing list archive at Nabble.com.
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>
>

-----
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Checked by AVG - www.avg.com
Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date: 11/13/13

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Don Wilhelm-4

Re: K3: Receive Ant Question

All the antenna configuration diagrams in the K3 manual show a COR on
the RX ant input.
See pages 41 through 44.

73,
Don W3FPR

On 11/13/2013 5:43 PM, Brian Alsop wrote:
> Guys,
>
> I thought he said RX antenna input. The COR is on the aux ant input.
> There is no COR on the RX antenna input (it's not needed, I think.)
>
>
> 73 de Brian/K3KO
>

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alsopb

Re: K3: Receive Ant Question

Hi Don,

Correct me if I am wrong.

The back panel diagram of the K3 shows two BNC's labed RX antenna. I
thought the thread originator was referring to this input path for a RX
antenna. It's what I use for RX antenna input.

I see "spark gaps" on the inputs on those pages you quote. I don't see
a carrier operated relay for the above BNC's. If it is there. I don't
see it on the schematics. The relay that is there is to complete the
rx/tx circuit when the BNC's are not in use. At least that's what I can
glean from the circuit.

The aux antenna BNC didn't come till later when the subrx and diversity
reception became a reality. It does have a real relay that goes click,
click with too much RF. It also has a spark gap protector.

73 de Brian/K3KO

On 11/13/2013 22:56, Don Wilhelm wrote:

> All the antenna configuration diagrams in the K3 manual show a COR on
> the RX ant input.
> See pages 41 through 44.
>
> 73,
> Don W3FPR
>
> On 11/13/2013 5:43 PM, Brian Alsop wrote:
>> Guys,
>>
>> I thought he said RX antenna input. The COR is on the aux ant input.
>> There is no COR on the RX antenna input (it's not needed, I think.)
>>
>>
>> 73 de Brian/K3KO
>>
>
> ______________________________________________________________
> 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
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date: 11/13/13
>
>

Don Wilhelm-4

Re: K3: Receive Ant Question

Brian,

There is a "*" next to that "spark gap" and a note on the diagram which
defines the "*" as a COR.
Yes, there also is a spark gap.

73,
Don W3FPR

On 11/13/2013 6:29 PM, Brian Alsop wrote:

> Hi Don,
>
> Correct me if I am wrong.
>
> The back panel diagram of the K3 shows two BNC's labed RX antenna. I
> thought the thread originator was referring to this input path for a
> RX antenna. It's what I use for RX antenna input.
>
> I see "spark gaps" on the inputs on those pages you quote. I don't
> see a carrier operated relay for the above BNC's. If it is there. I
> don't see it on the schematics. The relay that is there is to
> complete the rx/tx circuit when the BNC's are not in use. At least
> that's what I can glean from the circuit.
>
> The aux antenna BNC didn't come till later when the subrx and
> diversity reception became a reality. It does have a real relay that
> goes click, click with too much RF. It also has a spark gap protector.
>
> 73 de Brian/K3KO
>
>
>
>
>
> On 11/13/2013 22:56, Don Wilhelm wrote:
>> All the antenna configuration diagrams in the K3 manual show a COR on
>> the RX ant input.
>> See pages 41 through 44.
>>
>> 73,
>> Don W3FPR
>>
>> On 11/13/2013 5:43 PM, Brian Alsop wrote:
>>> Guys,
>>>
>>> I thought he said RX antenna input. The COR is on the aux ant input.
>>> There is no COR on the RX antenna input (it's not needed, I think.)
>>>
>>>
>>> 73 de Brian/K3KO
>>>
>>
>> ______________________________________________________________
>> 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
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date:
>> 11/13/13
>>
>>
>
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date: 11/13/13
>
> ______________________________________________________________
> 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
>

alsopb

Re: K3: Receive Ant Question

FB Don,

I see the *'s . At first viewing, they look like flyspecks on my
printout.

Thanks.

73 de Brian/K3KO
On 11/13/2013 23:42, Don Wilhelm wrote:

> Brian,
>
> There is a "*" next to that "spark gap" and a note on the diagram which
> defines the "*" as a COR.
> Yes, there also is a spark gap.
>
> 73,
> Don W3FPR
>
> On 11/13/2013 6:29 PM, Brian Alsop wrote:
>> Hi Don,
>>
>> Correct me if I am wrong.
>>
>> The back panel diagram of the K3 shows two BNC's labed RX antenna. I
>> thought the thread originator was referring to this input path for a
>> RX antenna. It's what I use for RX antenna input.
>>
>> I see "spark gaps" on the inputs on those pages you quote. I don't
>> see a carrier operated relay for the above BNC's. If it is there. I
>> don't see it on the schematics. The relay that is there is to
>> complete the rx/tx circuit when the BNC's are not in use. At least
>> that's what I can glean from the circuit.
>>
>> The aux antenna BNC didn't come till later when the subrx and
>> diversity reception became a reality. It does have a real relay that
>> goes click, click with too much RF. It also has a spark gap protector.
>>
>> 73 de Brian/K3KO
>>
>>
>>
>>
>>
>> On 11/13/2013 22:56, Don Wilhelm wrote:
>>> All the antenna configuration diagrams in the K3 manual show a COR on
>>> the RX ant input.
>>> See pages 41 through 44.
>>>
>>> 73,
>>> Don W3FPR
>>>
>>> On 11/13/2013 5:43 PM, Brian Alsop wrote:
>>>> Guys,
>>>>
>>>> I thought he said RX antenna input. The COR is on the aux ant input.
>>>> There is no COR on the RX antenna input (it's not needed, I think.)
>>>>
>>>>
>>>> 73 de Brian/K3KO
>>>>
>>>
>>> ______________________________________________________________
>>> 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
>>>
>>>
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date:
>>> 11/13/13
>>>
>>>
>>
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date: 11/13/13
>>
>> ______________________________________________________________
>> 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
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2012.0.2242 / Virus Database: 3222/6333 - Release Date: 11/13/13
>
>

dmb@lightstream.net

Re: K3: Receive Ant Question

In reply to this post by NY6C

I use this as well, and it works very well -- and very silently. Excellent
product.

73, Dale
WA8SRA

> I use this on the RX antenna:
>
> http://www.arraysolutions.com/Products/as_rxfep.htm
>
> ...works great.
>
> -Greg NY6C
>
> On Nov 13, 2013, at 3:16 PM, Don Wilhelm <[hidden email]> wrote:
>
>> Steve,
>>
>> The RX antenna input is protected by a Carrier Operated Relay. Other
>> than that, there is no relay to disconnect the RX input.
>> If your TX antenna is sufficiently separated from the RX antenna, there
>> is no problem.
>> How much is 'significant' is often a question, and the answer depends on
>> your particular antenna installation.
>> If you hear the COR relay operating, yours is not providing sufficient
>> isolation and you should look into an external device (likely a relay
>> will do) to disconnect the RX antenna during transmit.
>>
>> 73,
>> Don W3FPR
>>