On Wed, 17 Jun 2015 05:37:33 -0700 (PDT), Matthew Connor
wrote:

Good morning, all. I'm brand new to hands-on electronic repair so please pardon any silly questions.

I recently acquired a Geiger counter manufactured in 1962 and I am rebuilding it. The PCB is 4" x 4" and 0.062" thick. The part of the chassis to which it mounts has four steel legs that protrude 1.45" perpendicular to the plane of the chassis. The four corners of the PCB screw onto these steel legs.

I would like to know some options for making the PCB more shock resistant should the unit ever get dropped. Is there any such thing as, say, shock-resistant washers that could go over the four screws and sit between the PCB and the steel legs to which it's mounted? Or is there a better way?

1962 might be a CD-V700M counter. It matches your description:
https://www.google.com/search?tbm=isch&q=cd-v700m
I have one of those. How am I doing. Is there a reason why you
failed to disclose the model number?

Maybe small rubber grommets in the holes in the PCB. Something like
these:
http://www.customgasketmfg.com/Images/Rubber-Grommets-Bushings.jpg
If you can't find ones that fit, or you don't want to enlarge the
holes, use two rubber flat washers instead. You can get those in the
plumbing section at the hardware store. You may need to install metal
washer(s) on the grommet to secure the head. You can get fancy by
adding a coil spring under the screw head.

The problem with such simplistic schemes is that adding a washer
between the bracket and the PCB is going to raise the PCB by the
thickness of the washer. That means that front panel switches and
lights might not fit. If there is the usual big rotary switch in the
middle of the front panel, it too will need to be shock mounted,
probably with another grommet around the shaft.

Personally, I think you should make these modifications unless you
have a good reason to need additional shock resistance. Such
mechanical things really should be done with the initial design, not
as a retrofit. In 1962, phenolic (paper) PCB's were fashionable,
which might crumble if you try to "modify" them. I suspect you might
do more damage than good. However, if you MUST make it more shock
resistant, such as for transportation in a vehicle without shock
absorbers over a rotten road, some kind of foam lined packing case
would probably be helpful.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558