Great product. So easy to read compared to the originals.
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
The installation was straightforward and quite easy. Reliability and accuracy far exceed the original [aircraft’s] oil pressure/temperature systems. Also, the price was about a third of the cost to replace the gauge cluster.
- Customer
Casey R. from Oklahoma
- Aircraft
Cessna 172M
- EI Instrument
EI representatives… have been very helpful, truthful, and knowledgeable… We had no idea, that a few weeks later [after our purchase], we would need to have a Top Overhaul. What great timing! Having your engine monitor installed in our plane will hopefully help us keep it out of the shop for further engine repairs.
- Customer
Phillip B. From Oklahoma
- Aircraft
Cessna 210N Centurion / Turbo Centurion
- EI Instrument
The [unit] is easy to read and quick to respond. I have multiple EI units and have had good experiences with all.
- Customer
Thomas C. from Maine
- Aircraft
Maule M-5-235C Luna Rocket
- EI Instrument
The CGR-30P is a fantastic product and EI has excellent customer service. EI is the leader in engine monitors with a strong track record.
- Customer
William G. from New York
- Aircraft
Cessna 182Q Skylane
- EI Instrument
Currently have multiple EI Instruments in our aircraft. Quality and reliability are key.
- Customer
Jason Y. from Arizona
- Aircraft
Cessna 182A
- EI Instrument
Always very friendly and knowledgeable staff. Over time, I have purchased six different EI instruments for the two planes I own. The instruments are easy to install, very accurate, and dependable. EI has very stable and easy-to-operate instruments.
Phone service for ordering was quick and easy. Shipping was quick.
While the installation is not quite done yet, I have seen the unit in my aircraft with the engine running and the monitor producing numbers. It looks very good and I cannot wait to go flying with it!
Nice product and good product support!
- Customer
Kenneth G. from Michigan
- Aircraft
Grumman American AA-5B Tiger
- EI Instrument
Customer Service is far superior… with an excellent record of resolving … technical issues.
- Customer
C.J. R. from North Carolina
- Aircraft
Mooney M20C Ranger
- EI Instrument
We liked the price and the reputation of your company.
- Customer
Roy C. From Kentucky
- Aircraft
Piper PA-28-235 Cherokee Pathfinder
- EI Instrument