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MotorBikeLes · 7th Mar 2018, 9:41 pm

The S54A was preceded by an S54, very similar circuitry, except for a nuvistor in each Y channel, and another in the timebase. The transistors were "earlier" versions with odd numbers, and I recall the sweep on the fastest T/B speed on one I had was completely blanked. I replaced the unblank transistor with a CTV video output type (BF259 probably) - complete cure. Either the Y bandwidth was only 6MHz, compared with the 10MHz of the S54A, or it may have been 10HHz, but none achieved it.
Les

7th Mar 2018, 9:41 pm	#39
MotorBikeLes Nonode Join Date: Dec 2012 Location: Kirk Michael, Isle of Man Posts: 2,350	Re: Oscilloscope not used in years The S54A was preceded by an S54, very similar circuitry, except for a nuvistor in each Y channel, and another in the timebase. The transistors were "earlier" versions with odd numbers, and I recall the sweep on the fastest T/B speed on one I had was completely blanked. I replaced the unblank transistor with a CTV video output type (BF259 probably) - complete cure. Either the Y bandwidth was only 6MHz, compared with the 10MHz of the S54A, or it may have been 10HHz, but none achieved it. Les