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K3s RX Ant port question

Don Jones
 
Edited

Does the rx ant port disconnect during transmit? Do I need to install a TR switch on the rx ant port to protect the K3? Running 1500w with tx & rx ant's in close proximity to each other. Don't want to smoke my K3S. 
I'm not finding a straight answer in the manual. I do have a automatic tuner installed. 
Thanks, Don KO7I

Edit,
I  do have the sub receiver installed. 

Richard Williams
 

I would obtain  a DX Engineering Receiver Guard RF Limiter (DXE- RG5000HD.  Have used one for years in front of my receive antennas (Beverages,  HiZ 8, and SAL 30), and two of the three are close to my 160M phased verticals. 

And no, the RX port does not disconnect during transmit.

Dick, K8ZTT 

On Sat, Jan 11, 2020 at 21:06, Don Jones
<ko7i@...> wrote:

[Edited Message Follows]

Does the rx ant port disconnect during transmit? Do I need to install a TR switch on the rx ant port to protect the K3? Running 1500w with tx & rx ant's in close proximity to each other. Don't want to smoke my K3S. 
I'm not finding a straight answer in the manual. I do have a automatic tuner installed. 
Thanks, Don KO7I

Edit,
I  do have the sub receiver installed. 

Mel Marcus
 

If you look at the diagram for the RX antenna (kxv3a/b) you will see that the RX antenna is switched out during transmit. if you have a Kadybook look at diagram figure 8-25. make sure you engage the rx antenna via the button next to the power button.

Mel
NE9A

-------- Original Message --------
Subject: Re: [Elecraft-K3] K3s RX Ant port question
From: "Richard Williams via Groups.Io" <k8ztt@...>
Date: Sat, January 11, 2020 10:55 pm
To: "Elecraft-K3@groups.io" <Elecraft-K3@groups.io>

I would obtain  a DX Engineering Receiver Guard RF Limiter (DXE- RG5000HD.  Have used one for years in front of my receive antennas (Beverages,  HiZ 8, and SAL 30), and two of the three are close to my 160M phased verticals. 

And no, the RX port does not disconnect during transmit.

Dick, K8ZTT 

On Sat, Jan 11, 2020 at 21:06, Don Jones
<ko7i@...> wrote:
[Edited Message Follows]
Does the rx ant port disconnect during transmit? Do I need to install a TR switch on the rx ant port to protect the K3? Running 1500w with tx & rx ant's in close proximity to each other. Don't want to smoke my K3S. 
I'm not finding a straight answer in the manual. I do have a automatic tuner installed. 
Thanks, Don KO7I

Edit,
I  do have the sub receiver installed. 

Don Jones
 

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

Mel Marcus
 


Don

We used a beverage  ant on the RX antenna port during FD on the k3 and had no problems. That would have been a terrible design flaw if the k3 allowed the receiver to overload during transmit. Hope someone more knowledgeable jumps in to educate.

Mel 

-------- Original Message --------
Subject: Re: [Elecraft-K3] K3s RX Ant port question
From: "Don Jones" <ko7i@...>
Date: Sun, January 12, 2020 2:17 pm
To: Elecraft-K3@groups.io

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

 

All RX IN ports are disconnected by PIN diode
switches during transmit. They are also protected by carrier-operated relays. 

If the COR relay gets keyed by your RF or by another nearby TX, consider increasing separation between antennas or using a supplemental diode switch keyed by the KEY OUT signal. 

73,
Wayne
N6KR


On Jan 12, 2020, at 12:17 PM, Don Jones <ko7i@...> wrote:

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

Mel Marcus
 

Wayne

Thanks for that update. I knew that the K3 would not have been  built with that flaw.

Mel
NE9A

-------- Original Message --------
Subject: Re: [Elecraft-K3] K3s RX Ant port question
From: "N6KR" <n6kr@...>
Date: Sun, January 12, 2020 3:07 pm
To: Elecraft-K3@groups.io

All RX IN ports are disconnected by PIN diode
switches during transmit. They are also protected by carrier-operated relays. 

If the COR relay gets keyed by your RF or by another nearby TX, consider increasing separation between antennas or using a supplemental diode switch keyed by the KEY OUT signal. 

73,
Wayne
N6KR


On Jan 12, 2020, at 12:17 PM, Don Jones <ko7i@...> wrote:

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

Dave N3AC
 

Wayne,

Does that include the Aux Antenna - is it likewise disconnected during transmit?

Thanks,

Dave N3AC

On Sun, Jan 12, 2020, 16:07 N6KR <n6kr@...> wrote:
All RX IN ports are disconnected by PIN diode
switches during transmit. They are also protected by carrier-operated relays. 

If the COR relay gets keyed by your RF or by another nearby TX, consider increasing separation between antennas or using a supplemental diode switch keyed by the KEY OUT signal. 

73,
Wayne
N6KR


On Jan 12, 2020, at 12:17 PM, Don Jones <ko7i@...> wrote:

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

Mike Irizarry
 

I have a K3.  I do not believe either the receive ant port or sub receive port are disconnected like the main antenna ports.  There are some small protection diodes. I use the kd9sv front end protection for both. You can get them at dx engineering.


On Sat, Jan 11, 2020 at 9:58 PM Don Jones <ko7i@...> wrote:
Does the rx ant port disconnect during transmit? Do I need to install a TR switch on the rx ant port to protect the K3? Running 1500w with tx & rx ant's in close proximity to each other. Don't want to smoke my K3S. 
I'm not finding a straight answer in the manual. I do have a automatic tuner installed. 
Thanks, Don KO7I 

 

All RX antenna ports have series PIN diodes that open during TX.

Wayne

On Jan 12, 2020, at 11:39 AM, Mike Irizarry <michael.irizarry29@...> wrote:

I have a K3. I do not believe either the receive ant port or sub receive port are disconnected like the main antenna ports. There are some small protection diodes. I use the kd9sv front end protection for both. You can get them at dx engineering.

On Sat, Jan 11, 2020 at 9:58 PM Don Jones <ko7i@...> wrote:
Does the rx ant port disconnect during transmit? Do I need to install a TR switch on the rx ant port to protect the K3? Running 1500w with tx & rx ant's in close proximity to each other. Don't want to smoke my K3S.
I'm not finding a straight answer in the manual. I do have a automatic tuner installed.
Thanks, Don KO7I


 

Yes. But if the signal is still too hot, it triggers the COR.

Wayne

On Jan 12, 2020, at 2:00 PM, Dave N3AC <dcharing@...> wrote:

Wayne,

Does that include the Aux Antenna - is it likewise disconnected during transmit?

Thanks,

Dave N3AC

On Sun, Jan 12, 2020, 16:07 N6KR <n6kr@...> wrote:
All RX IN ports are disconnected by PIN diode
switches during transmit. They are also protected by carrier-operated relays.

If the COR relay gets keyed by your RF or by another nearby TX, consider increasing separation between antennas or using a supplemental diode switch keyed by the KEY OUT signal.

73,
Wayne
N6KR

----
elecraft.com

On Jan 12, 2020, at 12:17 PM, Don Jones <ko7i@...> wrote:

NE9A, um no, I'm seeing that the rx ant port when connected to the sub rx, is not isolated during transmit. I do have the Kady book too.

Don Jones

Sent via my wireless cell phone.

Don Jones
 

Thank you for the responses.

I'm a little up-tight about protecting the sub rx during transmit when running legal limit with the rx ant being very close the the tx ant (40 ft or less). The EMC engineer in me is saying add a T/R switch to the rx ant. 

73,
Don KO7I