Terminating the Receive Antenna Port on the Elecraft K3s can be beneficial in certain scenarios. Here's why:
1. Reducing Noise & Interference - An open port can act like an unintended antenna, picking up stray signals and noise, which might degrade reception quality. 2. Preventing RF Feedback - If you're operating in a high-RF environment, an unterminated port could introduce unwanted feedback into the receiver. 3. Protecting Internal Components - Some operators terminate unused ports to prevent potential damage from static buildup or accidental RF exposure. 4. Maintaining Signal Integrity - A proper termination ensures that impedance remains stable, which can improve overall receiver performance. If you're not using the port, a simple 50-ohm termination might be a good practice to minimize unwanted effects. You might find more details in the [Elecraft K3s manual](https://elecraft.com/pages/k3s-high-performance-transceiver-manuals) or other technical resources. 73, Dick, W1REJ -----Original Message----- From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On Behalf Of elecraft-requ...@mailman.qth.net Sent: Saturday, May 31, 2025 12:00 PM To: elecraft@mailman.qth.net Subject: Elecraft Digest, Vol 253, Issue 31 Send Elecraft mailing list submissions to elecraft@mailman.qth.net To subscribe or unsubscribe via the World Wide Web, visit http://mailman.qth.net/mailman/listinfo/elecraft or, via email, send a message with subject or body 'help' to elecraft-requ...@mailman.qth.net You can reach the person managing the list at elecraft-ow...@mailman.qth.net When replying, please edit your Subject line so it is more specific than "Re: Contents of Elecraft digest..." Today's Topics: 1. Re: KPA500 and KAT500 for sale (Jim Brown) 2. K3 RX Antenna OUT termination (Rich) 3. Re: K3 RX Antenna OUT termination (Jim Brown) 4. Re: K3 RX Antenna OUT termination (Rich) 5. Re: K3 RX Antenna OUT termination (Ted Edwards W3TB) ---------------------------------------------------------------------- Message: 1 Date: Fri, 30 May 2025 11:01:28 -0700 From: Jim Brown <j...@audiosystemsgroup.com> To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA500 and KAT500 for sale Message-ID: <25f54a22-6982-482f-adf4-0a22c52fc...@audiosystemsgroup.com> Content-Type: text/plain; charset=UTF-8; format=flowed On 5/30/2025 3:31 AM, Stephen Craven via Elecraft wrote: > configured for 115VAC The amp runs fine on 120V, and changing to 240V is trivially easy. 73, Jim K9YC ------------------------------ Message: 2 Date: Fri, 30 May 2025 16:58:02 -0400 From: Rich <rwnewbo...@comcast.net> To: Elecraft <elecraft@mailman.qth.net> Subject: [Elecraft] K3 RX Antenna OUT termination Message-ID: <d429a026-7cdd-493d-be74-64463beba...@comcast.net> Content-Type: text/plain; charset=UTF-8; format=flowed Should the "RX ANT OUT" be terminated with 50/75ohms. When only using the "RX ANT IN" BNC? Rich K3RWN ------------------------------ Message: 3 Date: Fri, 30 May 2025 14:04:01 -0700 From: Jim Brown <j...@audiosystemsgroup.com> To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 RX Antenna OUT termination Message-ID: <1a26c4c6-e8e5-4a9f-b5e0-90159731f...@audiosystemsgroup.com> Content-Type: text/plain; charset=UTF-8; format=flowed On 5/30/2025 1:58 PM, Rich via Elecraft wrote: > Should the "RX ANT OUT" be terminated with 50/75ohms. There's no good reason for doing so. 73, Jim K9YC ------------------------------ Message: 4 Date: Fri, 30 May 2025 17:12:25 -0400 From: Rich <rwnewbo...@comcast.net> To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 RX Antenna OUT termination Message-ID: <83264839-630f-4f3f-92b2-a39c520b3...@comcast.net> Content-Type: text/plain; charset=UTF-8; format=flowed Thanks, I have not done so for the last decade either, but over heard a discussion at Dayton so I was curious Rich On 5/30/2025 5:04 PM, Jim Brown wrote: > On 5/30/2025 1:58 PM, Rich via Elecraft wrote: >> Should the "RX ANT OUT" be terminated with 50/75ohms. > > There's no good reason for doing so. > > 73, Jim K9YC > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > rwnewbo...@comcast.net ------------------------------ Message: 5 Date: Fri, 30 May 2025 16:56:18 -0500 From: Ted Edwards W3TB <w3tb....@gmail.com> To: Rich <rwnewbo...@comcast.net> Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 RX Antenna OUT termination Message-ID: <caghfmtj-gl7aijoaw1rfg4__urz+1jru1sv3ezuv6egtwox...@mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Has anyone tried terminating like that? 73 de Ted Edwards, W3TB and G?PWW and thinking about operating CW: "Do today what others won't, so you can do tomorrow what others can't." On Fri, May 30, 2025 at 16:13 Rich via Elecraft <elecraft@mailman.qth.net> wrote: > Thanks, I have not done so for the last decade either, but over heard > a discussion at Dayton so I was curious > > Rich > > On 5/30/2025 5:04 PM, Jim Brown wrote: > > On 5/30/2025 1:58 PM, Rich via Elecraft wrote: > >> Should the "RX ANT OUT" be terminated with 50/75ohms. > > > > There's no good reason for doing so. > > > > 73, Jim K9YC > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net Please help support this > > email list: http://www.qsl.net/donate.html Message delivered to > > rwnewbo...@comcast.net > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > w3tb....@gmail.com > ------------------------------ _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must be a subscriber to post. Elecraft web page: http://www.elecraft.com End of Elecraft Digest, Vol 253, Issue 31 ***************************************** ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
