Custom EAS Receiver
(was TFT EAS-930A, now EAS-1)
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The commercially available TFT receiver commonly found in broadcast stations. This radio receives and detects the digitally coded warning from
NOAA/NWS and interrupts regular programming, automatically switching over to the emergency message, and broadcasting it on the public air waves.

There are three active receivers in the EAS-930(A); AM, FM, and NOAA's seven VHF weather channels.
The original unit had protective doors on the front panel. Behind the doors are screwdriver-adjustable decade switches to set the three fixed frequencies for the
station to monitor. I removed the switches and wired in finger-adjustable odometer type switches. There's a fourth bay for an optional module, which I didn't need. That
position became the home for a Signal Strength meter (S-Units and microvolts) and an audio level meter (VU).
Expanded views of the
modified graphic for
the front panel
(ignore the
blue guide lines).
Where do you get a decent meter movement for a 1U (1 3/4") equipment rack panel? Well, I found some really nice audio VU meters online. It's the only type they make
in this case style and is a mini version of the old studio VU (Volume Units) type of meter. Remember those? In the heavy bakelite case? This is the same, but plastic and
only 1 1/4" square. Cute, huh?

Okay, so I needed a matching Signal Strength meter to indicate "S-Units" and microvolts. Well, the only solution is obvious; take one of the meters apart and design a
new face.
After removing the scale card from
the VU meter, I taped it to a piece of
colored paper and scanned it at
600dpi resolution.

Then the scanned image was
imported into a photoshop type  
(photohouse) program.

There, I removed the numerals and
some hash marks and rescaled the
arc.

The final artwork was printed on
label stock, cut out, and pasted to
the original meter card.

The colors are slightly off, but I'm
going to change the internal LED's
color so that the meters will be
distinctively different for quick
recognition during operation.

One thing I got used to in US Army
Comms Intel (COMINT) is being able to
instantly know the location of a particular
knob or recognize a particular meter or
display. There was a lot of equipment
there and (literally) hundreds of knobs,
dozens of meters and an equal amount of
frequency displays. When things got busy,
you had to put your eyes and hands on the
correct things. In a darkened room,
specific identification becomes requisite -
and it lowers the "headache factor".
Original meter card scanned as a .jpg.
Card image after numbers have been removed in a
graphics program.
Card with Modified nomenclature added.
Next: Assembly Begins
Counter
Here's the draft printing
of the decal taped to the
panel to check alignment
with control mounting
holes.

Below it is the actual,
hi-res printing that has
been laminated, front
and back. The two-sided
lamination makes the
paper stable and
prevents adhesive bleed
through from the rear.
The acetate lamination
also holds better to the
thin double sided tape -
moisture absorption is
now of no concern.
The decal affixed to the
panel. Next step is to cut
out the holes with a #11
blade using the holes in
the aluminum panel as
guides.
Finally, with the controls
and knobs mounted.

The yellow LED confirms
that AC mains power is
connected -- red is the "on"
indicator.
Watch the video
Hear a typical EAS
Trigger Tone