Rebuilding An Eberline RIA-1

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
Post Reply
User avatar
Adam Ingle
Posts: 27
Joined: Mon Oct 11, 2010 10:04 pm
Real name: Adam Ingle
Location: Springfield, MO

Rebuilding An Eberline RIA-1

Post by Adam Ingle » Wed Feb 06, 2013 2:10 am

Looking around on eBay, I came across an Eberline RIA-1, Remote Radiation Monitor. Looked like a great piece of the 1950's Americana or something you'd see on an old Navy ship. (Although, when opening it up, I noticed what appeared to be a date stamp on the meter of April 2000.)

Unable to find any documentation, other than an old government report which only made mention to a facility having this particular unit, I went ahead and purchased it. If nothing else, it makes a great "wall hanger."

It did not come with any of the remote probes designed to interface with the alarm; only the analog meter, lamp and horn.

I removed the circuit board and while discussing several different ways to reconfigure it to work with another interface, a friend from work simply stated, "Just use an Arduino and be done with it." I hesitated for a moment at first due to potential cost of replacement and I also wanted to preserve the elegant/clever techniques early Eberline engineers implemented into the system. Quick search revealed that about $20 for a DigiSpark Arduino, USB-to-serial dongle and a relay board would do the job quite nicely.

After a couple of hours about two dozen lines of code, I now have a working interface and alarm.

Getting the analog meter on the front working will be the next goal.

Breakdown of the alarm:

DigiSpark - project - $12
SainSmart 2-Channel 5V Relay Module - $6
USB-to-Serial Adapter - $2
Toggle switch - Free
All other parts - original to the unit

Within the alarm there is a USB-to-serial dongle that supplies the necessary serial communication as well as power to the DigiSpark and relay board. The GeigerGraph software supports serial output to trigger external alarms connected to the computer, launch applications, send e-mail/pager/text alerts, etc. CPM thresholds of any magnitude can be configured in the software interface. Radiation detection is provided by a Medcom CRM-100 with serial interface into the computer.

When an event is triggered, there are two supported alarm modes the DigiSpark can run. The first mode is 0.5 second flash and synchronous horn blast followed by a 0.5 second pause. The second mode is a 1 second flash and 1 second pause with no horn blast. These modes are controlled by the toggle switch mounted on the front of the alarm.

It is quite loud. I used my "ears" from the riffle range while testing to avoid any headaches.
As you can see here:


Adam Ingle

Photo 1 - Full picture of the setup
Photo 2 - Guts of the alarm (Forgive me, I know it's not yet glamorous.)
fullview.jpg (561.85 KiB) Viewed 918 times
alarmguts.jpg (584.01 KiB) Viewed 918 times

Post Reply