McKay Dymek DA100E unusual failure mode
 

Ron Hardin wrote:

The antenna rod, which is pressed onto the screw mount attached to it,
the whole thing then screwed by the customer onto the antenna base,
works its way off what it has been pressed onto.

The rod, in my case, fell to the ground and was standing bottom straight
up in the snow.

I simply (ha! the screws rust) replaced the whole thing with the
antenna rod assembly from one of my two dead DA100E's. (I have
six active, and one spare; and have accumulated two dead ones,
at a rate of one failure every 18 DA100E-years.)

I'm cooling the rod's base and heating the rod, and will see if it
can be pressed back together or not. Just pushing doesn't do it.

The funny thing is that, now that I look, another one is in the
process of working its way off too.

I don't get the mechanics of it.

Success. I don't know how much the temp difference helped.

Drill a hole in the short 2x4 just large enough to accommodate
the 2nd segment of the antenna, which is also the diameter of the ball
on the end. Put the hole at the end, and position it off the end of
a basement stair, with the antenna pointing down through it.

That supports the base element of the antenna, recently heated;
insert frozen screw mount, tap in with hammer. Goes right in.

I pre-coated each with DeOXit (brush-on) so they make decent
electrical contact too.

Now wait for the next outdoor one to fall apart and I have a
replacement.

--
Ron Hardin


On the internet, nobody knows you're a jerk.

McKay Dymek DA100E unusual failure mode
 

Ron Hardin wrote:

Success. I don't know how much the temp difference helped.

Drill a hole in the short 2x4 just large enough to accommodate
the 2nd segment of the antenna, which is also the diameter of the ball
on the end. Put the hole at the end, and position it off the end of
a basement stair, with the antenna pointing down through it.

That supports the base element of the antenna, recently heated;
insert frozen screw mount, tap in with hammer. Goes right in.

I pre-coated each with DeOXit (brush-on) so they make decent
electrical contact too.

Now wait for the next outdoor one to fall apart and I have a
replacement.

--
Ron Hardin

---------------------------------
You might try some heavy duty silicon sealant. "Smeared in a very
smooth bead around the junction of the vertical element nd the case
meet.

I had a similar problem on a home made active antenna that uses a
attachment scheme very similar to the DA100D. I haven't seen the "E"
varient, so I don't know how similar they are. From your discription
they
sound to be nearly the same from an external perspective.

I was kind of shocked when I saw how similar my scheme was to the 100D.
My home brew has been in service for ~30 years. The electronics are
lacking
by todays, or even 1983 standards, but it keeps on working fairly well.
It is
in service at my parents, dad likes toknow the "Exact" time. Before the
net
came along, WWV was about as good as most of us could get.

My refference to 1983 is in regards to the "Burhans" designs in Radio
Electronics of that year. I wish I had known about his designs back
then.

Terry