[GreenKeys] jack field polarity?

[John W9DDD]

Darn, I hadn't even thought about that.   I wonder if any of the TUs that provided a TRS jack can be counted on to provide a standard.  I'll be taking a look at my TU-170 to see what it "says".  

I just finished finishing a 3 jack + loop supply that was in a batch parts I picked.  There were drilled holes for jacks that were empty and  a TRS jack that was labeled meter.  That seemed redundant since there was already a meter there.  This 4th jack was on a different face of the box than the other 3, so I wonder if it is wired consistently as far as polarity.  That is intended to be a scope jack with a 130 resistor across the T & R contacts.  

Anyhow no thought was given to polarity since up to now nothing was polarity sensitive.  It seems most TUs were designed on the premise that you're drive a single device and as a result you probably have transistor with emitter attached to circuit common and that being tied to earth.

Back to drawing board.

John, W9DDD


> On Jan 19, 2023, at 3:23 PM, W2HX <w2hx at w2hx.com> wrote:
> 
> Hi all,
>  
> I’m redoing my loop jacks.
> https://w2hx.com/x/TTY/JackField/IMG_1166.JPG
> https://w2hx.com/x/TTY/JackField/IMG_1170.JPG
> https://w2hx.com/x/TTY/JackField/Visio-tty%20jackfield.pdf
>  
> I am changing it from the long frame style (TRS)
> https://w2hx.com/x/TTY/Plugs/20220208_162853.jpg
> https://w2hx.com/x/TTY/Plugs/20220208_162640.jpg
>  
> to the more typical plugs (TS).
> https://w2hx.com/x/TTY/New%20Jackfield/20230119_133200.jpg
> https://w2hx.com/x/TTY/New%20Jackfield/20230119_133210.jpg
> https://w2hx.com/x/TTY/New%20Jackfield/20230119_133216.jpg
>  
> In the past, I don’t think any of my equipment cared about polarity. But I’ve recently added a CV-2460 into the shack and it does care about polarity. Obviously, I can make the tip/sleeve whatever polarity I want. But I was curious what others do in their shacks. Do you make the tip positive? Would anyone care if the tip was negative? Any thoughts or opinions? Again, I don’t think it matters but just curious what you guys think.
>  
> 73 Eugene W2HX
> Subscribe to my Youtube Channel: https://www.youtube.com/@w2hx/videos
>  
>  
> ______________________________________________________________
> GreenKeys mailing list
> Home: http://mailman.qth.net/mailman/listinfo/greenkeys
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:GreenKeys at mailman.qth.net
> 
>>>> Jordan Spencer Cunningham's GreenKeys Search Tool: https://teletype.net/gksearch
>>>> 2002-to-present greenkeys archive: http://mailman.qth.net/pipermail/greenkeys/
>>>> 1998-to-2001 greenkeys archive: http://mailman.qth.net/archive/greenkeys/greenkeys.html
>>>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool: http://comcents.com/tty/greenkeyssearch.html
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to w9ddd at tapr.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20230119/7a9bb68e/attachment.html>