Yaesu FT-290RII Battery Box Coaxial Connector Sze?

[K8ERV]

That's a lot of hope.

Because, if the series diode was placed there for proper operation, then you would measure zero voltage at the input pin, because the diode would be blocking that direction.


73

Yes if the diode were perfect, but all have some reverse leakage. That is why I said you would need a high input Z meter.

And I said MAY. (CYA).

TOM K8ERV Montrose Colo

[W1VT]

I checked my battery box and yes, the polarity is clearly marked on the box. Shield is marked as +. I also verified my wiring--the red wire goes to the shield. I used the normal ham convention of red wire for the positive and black for the negative lead. Always good to check--my memory typically becomes fuzzy on these sorts of details after a decade or two after I've wired something up.

[K8ERV]

--my memory typically becomes fuzzy on these sorts of details after a decade or two.

Mine only takes two days.

I hate reversed polarities, usually NO reason for it.

TOM K8ERV Montrose Colo

[W9GB]

BE CAREFUL, to properly wire that DC coaxial connector !!!
In the 1960s through the early 1980s, Japaneses mfg. we're inconsistent (some equipment was switchable for positive or negative ground) ...
The center pin on the DC coaxial connectors can be NEGATIVE or POSITIVE for 13.8 VDC.

Yaesu FT-290R II Manual, READ manual, such as page 23.
This radio uses NEGATIVE for Center Pin.
http://www.foxtango.kc9foz.com/Eighties/FT-290RII.pdf

Coaxial DC connectors with center pin size of 2.1mm and 2.5mm are common,
with either 5.0 or 5.5 mm length of barrel.

Zac -

Thanks for checking your personal Yaesu FT-290RII 2-meter radio.

Ross -

It is IMPORTANT that you MARK this DC power cable (special color, yellow or red flag) as Center Pin Negative and Outer Shell as Positive -- so that it will not be used with other equipment (Positive Center Pin), which would damage that radio equipment!!

Good luck with project.

w9gb