I really appreciate the quality of communication about my order. The instrument offers the right functionality (being a primary instrument) in the right form factor for my application.
A-1 Carb or OAT Instrument
Don’t Need Your Glasses To Read
- Large digital backlit display.
Interpret Your Readings Faster
- The digital display allows for quick trend analysis.
Budget Friendly
- Same precision found in the most advanced analyzers on the market, but the A-1 Carb or OAT Instrument won’t break the bank.
Accurate, Dependable & Easy To Use
- LCD sunlight viewable and backlit for night operation.
- Electronics International consistently has been a leader in digital engine instrumentation since 1979.
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Product Overview
A-1 OAT Overview

OAT or Carb Temp
Electronics International’s A-1 instrument provides pilots with the precision and stability needed in order to accurately monitor Outside Air Temperature or Carburetor Temperature while in-flight.
Ice Zone Warning
Not only will Electronics International’s A-1 display Outside Air Temp with a stable, one-degree (Fahrenheit) resolution, it also comes complete with an “Ice Zone” light that alerts the pilot when the Outside Air Temperature could possibly contribute to ice forming in the aircraft carburetor.
Reliable Probes
A-1 OAT Kit Includes:
- One (1) P-110F Fast Response EGT Probe
- One (1) P-100 CHT Probe
- One (1) P-128 OAT/Carb Probe
A Monitor is only as good as its probes. That’s why Electronics International (EI) has taken the development of its probes, connectors, and accessories very seriously. EI has been designing and manufacturing probes for over 30 years. All of our probes have been designed in-house by our engineering team. Our team has studied, tested, and designed temperature probes since the 1970′s. They have written research documents such as The Pilots Manual – Leaning and Diagnosing Engine Problems and Accurate CHT Measurements. Just as a Monitor is only as good as its probes, a probe is only as good as its connector. That’s why EI’s engineering team developed EI’s proprietary OLC-1 connector. The OLC-1 connector greatly increases reliability and reduces installation errors as compared to traditional type connectors. Whether you’re looking for a reliable and accurate CHT, EGT, TIT, or various other probe types, EI has what you need. With more than a half million probes sold and tested you can count on EI’s reliability.



Prices
Retail Prices
Package includes:
- A-1 Carb or OAT Instrument
- P-128 OAT Probe
- XP-6′ Precision Thermocouple Cable
- Wire Harness
- Operating & Installation Instructions
Description
Package
Retail Price
A-1 Carb or OAT Instrument
-
$428

Specifications
Specifications
Dimensions
2.5″ x 2.5″ x 3.65″ Deep, 2 1/4″ Flush Mount
Weight
7 oz. (Unit), 1.6 oz for a probe & 2 oz for a 6′ Cable
Power Requirements
7.5 to 30 Volts, 1/10 Amp
Ice Zone Warning
Light is lit when displayed temperature is between 10°F and 39°F.
Display
Viewable in direct sunlight, with dimmable 12 and 24-volt backlight control lines.
Intensity Control
Separate intensity control lines allow you to independently control Ice Warning Zone and Backlight intensity.
Probes
Type K Thermocouple, Ungrounded

Videos
Product Videos
Documents
Documents & Manuals
Testimonials
Customer Testimonials
I installed a VA-1A Volts/Amps Insturment [sic] in my 1970 V35B to replace the original analog amp meter. What a great dual purpose digital gauge! Installation was simple and the product is very well made. It goes well next to my SuperClock I installed a couple of years ago. EI makes great products and this one will satisfy the most discriminating owner.
- Customer
Brewer P. from Mississippi
- Aircraft
Beechcraft Bonanza V35B
- EI Instrument
Nice unit. EI is the best!
Pleasure supporting folks with like values.
Nice Instrument, all the electrical information I need in one place. [I chose EI for its] performance and price.
- Customer
David C. from the United Kingdom
- Aircraft
Scottish Aviation Bulldog
- EI Instrument
Great Service.
- Customer
Flying Academy from New York
- Aircraft
Piper PA-28-161 Warrior
- EI Instrument
Great Product, that provides a lot of very helpful engine data in an easy to use and see display! We are already finding cylinder cooling issues that we would’ve never known about before, and probably explains why we’ve had to replace that specific cylinder in the past. EI customer service on questions on how we wanted to set ours up was very helpful and positive. The CGR-30 had quite a few positive reviews online from other users.
- Customer
Ryan O. from North Dakota
- Aircraft
Cessna 182D
- EI Instrument
The FP-5l I had installed is easy to use and so accurate it’s almost scary. When I find a company that produces a product that good I stick with them. The fact that these instruments also look so darn good didn’t hurt either.
Great service for Electronics International. Very helpful with what it needed for my aircraft. My mechanic has installed several of these units and highly recommended this for my aircraft.
This is the third EI instrument I am having installed in “Lillybelle .” I am impressed with the ease of operation, the affordability and the accuracy of each of these instruments. For years I trusted my life to 50+ year old gauges. Now I don’t have to. What a relief!
- Customer
Charles M. from South Dakota
- Aircraft
Cessna 150F
- EI Instrument
I was able to try out the CGR-30P in a flight school plane. I was very impressed with the ease of use, visual quality, and information provided on the main screen… I feel it will pay for itself in fuel savings, and extended engine time before overhaul.
- Customer
David M. From South Carolina
- Aircraft
Cessna 182J Skylane
- EI Instrument
Works great!
- Customer
Ronald G. From Washington
- Aircraft
Cessna 195A
- EI Instrument