K9YC writes:
> There is no problem with V- bonded at load equipment (the rig). The problem
> is bonding at the power supply, and that is EASY to fix
> -- indeed, many (most?) power supplies are built either with V- NOT bonded,
> or with nothing chassis-referenced and a removable jumper
> at the output. All Astron supplied I've looked at are built this way --
> indeed, all I've looked at had the bond to the mounting stud of terminal
> strip that was insulated from the chassis by paint. So they were NOT bonded,
> and neither was the green wire, which went to the same lug.
My observations of Astron ground wiring are similar to yours but I come to a
different conclusion.
The V- goes to the terminal strip lug and the terminal strip lug is attached to
painted chassis by screw, but I would assume that this makes a poor and
intermittent connection between V- and chassis ground.
"Insulated by paint" seems like a very poor idea. It's like someone thought "my
boss told me to do this, I don't think I it should be done, and if it isn't
worth doing then it isn't worth doing well" :-)
Lifting the ground connection to V- is a very common modification to Astrons
and some sources (e.g.
http://www.repeater-builder.com/astron/astron-intro-stuff.html ) tell me that
Astron has vacillated between grounding V- to cabinet and not grounding and
isolating it with 3K ohm resistor over the years.
Tim N3QE
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