[R-390] SP 600 Wiring Colors

[rbethman]

Tisha,

I don't know why, but the Northern Radio Variant doesn't have this 
issue.  Perhaps I hould say that MINE doesn't.

I obtained it in 2004.  I haven't had a lick of wire harness issues. 
Perhaps it is due to how it was kept and stored.

The only thing that has happened, is that going to replace a #47 bulb 
attached to the back of the meter, shorted out the meter.

So the meter doesn't work anymore.  The movement is cooked.

It still works very well.  The previous took care of all the BBODs.

There are Orange Drops in their place.

Bob - N0DGN

On 4/30/2014 9:11 AM, Tisha Hayes wrote:
> Funny,
> The one commonality I have seen with SP-600 wiring.. if you have even the
> slightest provocation, tear it out and replace it. Especially anything that
> penetrates to the front panel.
>
> On the '600's I have known (I really cannot say love, they are like a
> stepchild that you just know is up to no good), the wiring insulation turns
> to a million little crunchy pieces as soon as you remove the front panel.
> This usually happens where the wiring goes through those rather sharp-edged
> circular holes in the lower chassis.
>
> So you do the standard thing; sigh, snip off the wire lacing (and it was so
> pretty looking) gently work that one wire loose, unsolder it from whatever
> pot or switch it was attached to and thread on a thin piece of spagetti or
> heat-shrink tubing. Usually it takes an entire six to ten inch length of
> tubing and as you are going more of the insulation chunks are breaking off
> of that wire. Looking closely you see that many of the conductive strands
> are corroded and broken on that one wire. You bravely muddle along and now
> that wire looks all pretty.
>
> Hmm, getting ready to re-bundle everything else and you find that you
> cracked insulation on three or four other wires while working on that one
> wire... Darn. Now the experience gets repeated on those too. This is
> turning into a day-killer.
>
> Ok.... it is now 11:45 in the evening, you have done a half-dozen of those
> wires. A few times you find that the cracked insulation extends all the way
> into the lower chassis but you are set in your mind; "there is no way I am
> cutting apart the lacing in the lower chassis". Yea, keep thinking that,
> maybe it will help you sleep at night. Wait until you need to do something
> silly like replacing a bad paper cap or BBOD."
>
> All this happens because you wanted to fix a slipping tuning dial. Maybe in
> your zest for cleanliness you disassembled the brass plate that retains the
> geartrain under the front panel so you could make the tuning bezels look
> pretty. (been there, done that) and you used brass cleaner to make all of
> that stuff look nice. Maybe you were really foolish and used something even
> in the slightest bit greasy so the edge of the tuning dial is slightly
> slippery so the brass wheel that is driven by the tuning knob is no longer
> gripping the edge tight enough (that is what usually causes a slipping
> tuning knob, weak hairpin springs, corrosion on the cadmium plated front
> pan and the little gear carrier that is supposed to be spring loaded
> against the edge of the display disk, all quite clever for its day.).
>
> BTW, even though it caused me almost a week of grief, fixing other things
> that geartrain looks spectacular! I strongly recommend that if you have
> metal that needs to be polished, give "Simichrome Polish" a try. It smells
> ammonia based but things I have polished ten years ago still look brand new.
>