Since the original software is outdated, the enthusiast community has created modern alternatives. For Windows, you can often capture the meter's ASCII data stream using a terminal program like PuTTY. For open-source users, the sigrok project offers excellent support for the 22-805. The serial communication parameters are 600 baud, 7 data bits, no parity, and 2 stop bits , with the meter transmitting readings as a continuous ASCII string.
That's the feature activating to save the battery. It will turn off after approximately 15 minutes of inactivity.
Incorrect readings or a fading LCD usually point to a low battery. Replacing the Battery Turn off the multimeter and disconnect both test leads. Remove the screws from the back cover of the housing. Carefully lift off the back cover.
The manual, often a crumpled pamphlet found in the bottom of a toolbox, outlined a specification sheet that was modest but respectable for its price point: radio shack 24 range digital multimeter 22-805 manual
The 22-805 can handle a wide variety of electrical tasks:
The input value exceeds the current range setting. Turn the rotary switch to the next highest setting.
Finally, the manual is now a historical document. For collectors and restorers of vintage electronics, the original 22-805 manual is as valuable as the multimeter itself. It confirms calibration procedures using obsolete batteries (the 9V and AA), explains the limitations of the 200mA fuse, and describes the device’s 1,000 ohms-per-volt sensitivity on AC ranges—a specification that would be considered laughably poor by today’s standards. Studying the manual today reveals how much measurement technology has advanced, but also what has been lost: the expectation that the user would read, understand, and respect the tool before turning the dial. Since the original software is outdated, the enthusiast
: Always discharge capacitors before testing them or the circuit they are in.
Always start with the highest range if the value of the circuit under test is unknown. This prevents overloading the meter. 1. Measuring AC and DC Voltage
The LCD flickered to life, the backlight a ghostly green in the dim basement. The serial communication parameters are 600 baud, 7
Allows precise measurement across various electrical parameters.
Temporarily freezes the displayed value for easy reading after disconnecting the probes.