American Diagnostic Corporation (ADC) Proscope 2.5v - Manual (Page 8)

Instrument head Thread/connection Service
will is required
not connect damaged
Wrong specula Use only Welch Allyn brand
Specula will not used or compatible
attach properly
Specula mount is damaged Service required
Loose or misaligned Lens mount Service
magnifying lens is damaged required
Lens is dirty Clean with lint free cloth
Poor or obstructed view
through lens Lens is damaged Service required
Lamp near end Replace the lamp with
Dim light of useful life ADC part #5211-4
output
Batteries are Replace with fresh
depleted “C” batteries
Visible corrosion on Damage from excessive Service
instrument or accessories moisture required
Ophthalmoscope Troubleshooting Guide
Trouble Area Possible Cause Corrective Action
Aperture dial is Rotate Aperture dial
between positions
Lamp Burned Replace the lamp with
No light output out ADC part #5210-4
Wrong Lamp Replace the lamp with
Installed ADC part #5210-4
Batteries are depleted Replace with fresh “C” batteries
Instrument head
will Lamp not fully inserted Re-insert lamp
not connect
Thread/connection is damaged Service required
Spot is not The aperture dial is not centered Move aperture dial to
centered the full detent position
Lamp near end of useful life Replace the lamp with
Dim light ADC part #5210-4
output
Batteries are depleted Replace with fresh “C” batteries