Hi all,
A point I failed to make in my comments below is that the goal of
anti-static measures is to keep everything at the same potential (and
not necessarily to 'ground things').
For instance, all my tools touch my anti-static mat before I use them,
and when I remove a device which is shipped in anti-static bags or the
black foam from its anti-static material, I place the bag or foam on my
anti-static mat first, then remove the device and place its leads on the
mat. That assures that anything originating beyond the bounds of my mat
will be equalized to whatever potential exists on the mat - there should
be no static potential difference between items that reside on my mat.
73,
Don W3FPR
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Hi all,
While I can state that Ron's comment about the K2 is typically true, the
static tolerance of thru-hole ICs and transistors is lower than it was
back in 1998 or even 2006 (OK, I picked those years as a guess). Many
current DIP mounted devices are really SMD devices with DIP leads and
can be as static sensitive as the devices in the K3 and KX3.
Despite the "touch grounded metal" instruction in the K2 manual, I do
see some repairs come in with failed firmware ICs, and rarely, but not
zero, some 'normal' ICs on a new build.
My best guess is that those parts were damaged due to a static charge.
Whether the builder did not follow the "touch a metal ground" or not I
cannot tell, all I know is that it failed.
When possible, use an anti-static mat and wrist strap when handling ICs
and transistors, especially during periods of low humidity. Do not work
on carpet without them and do not wear nylon clothing - and don't
shuffle your feet on the floor while working.
The minimum should be a wrist strap connected to the green-wire ground
in your house. You can use a banana plug in the round pin of an
electrical receptacle, but before you trust it, get one of the
receptacle testers and make sure that green wire ground is intact - some
are not.
Whether your anti-static precautions are 'overkill' for the task to be
accomplished will never be known. Take whatever precautions make you
feel comfortable with the risk factor involved. Doing nothing or
ignoring the static damage probability is not acceptable unless you are
willing to accept the risk.
I suggest that you do not connect the wrist strap to a separate ground
rod that you have for your hamshack unless that ground rod is also
bonded to the utility entrance ground rod.
It is off this topic, but if your ground rods are not connected to the
utility entrance ground, it is a safety hazard should something in the
house *or* your shack develop a fault. In addition, it is a violation
of the NEC (those codes are written for your safety).
73,
Don W3FPR
On 9/19/2016 4:12 PM, Ron D'Eau Claire wrote:
Note that the K2 manual does not make much of an issue about an anti-static mat. It's on
the bottom of the anti-static priority list Wayne compiled. In the interest of full
disclosure, I built my K2 while most of my stuff was in storage, working solely on a
small wooden drawing board using my ESD-Safe iron. I simply did the recommended
"touch a ground" before each time I reached for a transistor, i.c. or pc board
and experienced no problems whatsoever. Sixteen years later the K2 is still going strong.
73, Ron AC7AC
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