Re: [Tek 485] No intensity control


marcosjl31@...
 

On Wed, Mar 3, 2021 at 07:00 AM, Ozan wrote:
Are you still seeing ~ -61mV as before at collector of Q1548 with no dot on
the screen? With no dot on the screen base of Q1544 should be closer to 6V. If
base is still at ~1V please check R1536 for drift to >2.2M, CR1539 for leaky
diode, Q1544 for low hFE.
I see ~42mV at collector of Q1548, no dot on screen in XY Mode.
Base of Q1544 is at ~1V, HFE measured with a TC1 tester : 214
CR1539 is ok : ~.6V and 0L
R1536 measured in circuit gives : 300kohm and 100kohm (when inverting the test leads of DMM).

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