TI-5640 E CODE - Texas Instruments TI-5640 Calculator

See following diagram. I think it is carbon type microphone and seems same as required by you. Wire color codes are Black and Red are switch to enable audio circuitry on remote device (Push to Talk Switch, Usually in transmitters), White and Green are audio signal and shield.
Print 51.TIF (2 pages) (mypicsonline.net)

Roadking 5640 require dynamic type microphone.
Radio Code Definitions; Specifications - ROAD KING RK5640 Owner's Manual [Page 17] ' ManualsLib

Wahl Micro Groomsman Trimmer

push on and turn

Wahl Home Products Micro Groomsman 5640 600

wd 40 is a lubricant.you want to clean the rollers with a cleaner.
try some isopropynol alcohol

http://www.manualslib.com/manual/169832/Texas-Instruments-Ti-5640.html

Follow the instructions on pages 2-3 of this manual: http://www.fixya.com/support/p131694-texas_instruments_ti_5640_calculator/manual-5037

Follow the instructions on page 2 of this manual: http://www.fixya.com/support/p131694-texas_instruments_ti_5640_calculator/manual-5037

http://www.heasterlawson.com/texintielcal3.html


click image above to enlarge Item No.: texintielcal3
Regular price: $6.99
Sale price: $4.99Save 29%



Texas Instruments (TI) Electronic Calculator Ribbon Models - TI 320V/5317/5640/5650/5660
Sold as each



Availability: Usually ships in 2-3 business days.

texintielcal3Regular price: $6.99
Sale price: $4.99Save 29%

See page 2 of this manual: http://www.fixya.com/support/p131694-texas_instruments_ti_5640_calculator/manual-5037

Texas Instruments TI-5640 Calculator Paper not advance

From the manual:

"To clear an error or overflow, press [CE]. The memory is not cleared unless the error or overflow occurred in a memory calculation."