555/Repairs: Difference between revisions

From TekWiki
Jump to navigation Jump to search
(Repair Info)
 
No edit summary
 
Line 14: Line 14:


It is also advised to check the HV oscillator tube 6CZ5 and capacitors in the HV section
It is also advised to check the HV oscillator tube 6CZ5 and capacitors in the HV section
[[Category:Instrument repair reports]]

Latest revision as of 09:00, 6 January 2020

As with any vintage instrument, capacitors needs to be checked. Electrolytic capacitors are used in both power supply and indicator unit for filtering.

Also multi-section electrolytic capacitors C1093 and C2093 are used for low frequency compensation in vertical Amplifiers. All of these caps needs to be checked for leak and may require replacement/reforming.

Any paper capacitor used also need to be checked/replaced, for eg. C793 in Power supply AC Regulator section.

Two fuses - F1054 and F2054 - are used in the plate line of distributed vertical amplifiers (Underside of the chassis) If they are blown, it can load the screen bias resistor R1218/R2218 and potentially cause it to blow open. This can lead to loading the grid line driver cathode follower and V1033/V2033 resulting in no vertical sweep for the affected beam. Check the plate voltage of the V1033/V2033 and for a working VAmp, it should be ~178V DC.

It is also advised to check the HV oscillator tube 6CZ5 and capacitors in the HV section