[Kenwood] TS-520SE receiver brain teaser

[Tim Billingsley]

OK I am getting mixed signals on this ...

>"There should NOT be a dead short between the centre conductor and ground of the chassis mounted SO-239, make and model of radio notwithstanding. It appears that there is a short inside the radio (or a bad SO-239 jack) Cheers and Good Luck... "
>

> *"A simple test of the suspected short in the radio itself, is to 
> simply attach a wire to the center connector at the radio.  If you 
> hear a signal with only the center connected, then your radio is not 
> shorted internally. " *

This is what I have setup currently and the radio hears very well

>  
> *"The radio itself, being a tube type, will possibly show a short due 
> to the configuration of the final amplifier.  "
> *

OK I am, as I stated, visually challenged, but from what I could make 
out the center connection of the 239 goes to an inductor and into 
chassis ground after that ... again as I stated I may have lost track of 
the trace and could be mistaken and I do not have the schematic here 
with me, it is with the radio some 40+ miles away.

> *
> "However, if it is truly shorted as you say, the radio will be totally 
> deft at all times. " *

This is not the case at all. The receiver picks up signals very well if 
only the center pin of the PL-259 or just a simple wire is inserted into 
the SO-239, but this does not explain the behavior of the radio when 
even a "naked" PL-259 is connected. I cannot see the PL-259 with no coax 
at all having any profound effect on the radio but in fact it does. As I 
previously stated I connected 3 different pieces of coax that I verified 
the continuity or lack thereof as the case may be between the center and 
shield and the stand alone PL-259 and all (according to the RatShack 
meter I had available) appeared to be in good working order.
As for previous activities involving an antenna "for ham bands" the 
radio prior to being moved served me very well connected to a 40 meter 
inverted "V" fed with  RG-213. The house that this radio is sitting in 
now is a late 1800's Antebellum home with Knob and Post wiring and few 
if any grounds ... not sure what bearing that may have but some of you 
EE guys may be able to shed some light on that if it applies in any way.

I don't see where impedance mismatch would affect this in the way I have 
described but as I stated I am still a young fellow and I have yet to 
see it all ... on that note ...

>"*I give the details because you inferred you were a young and inexperienced ham."*
>  
>
Perhaps I misrepresented myself a bit ... young is a relative thing I am 
38 and an Extra Lite ... I do not know it all by any means but I have 
been around the feed lot a couple of times and I am reasonably familiar 
with the lay of the land and where the highlights exist, but in my 
humble inexperience I always come back to the reflectors where the vast 
cumulative knowledge and experience far exceed anything that I will most 
likely experience in the next 40 years of my life.

Thanks to all for your time and attention and if anyone has additional 
wisdom to apply to this riddle please don't hesitate to let us hear from 
you.

Good morning all and 73
Tim