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Old 12-13-2008, 06:06 PM
AndrewM AndrewM is offline
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Join Date: Feb 2008
Location: Victoria, Australia
Posts: 121
Little wonder you have reception issues as Q209 forms part of the RF AGC circuit for the VHF tuner. The correct part should be a 2SC677. The base of this transistor goes to VR201 wiper which is a 470 ohm trimpot to adjust VHF Tuner AGC level. The trimpot ends connect via R207 560 ohm to 18v IF panel supply and the other end goes to a centre tap on VIF transformer 2.

Voltages on the transistor should be:
Base 15v (11v with signal)
Collector 12v
Emitter 0v (4.9v with signal)

Hope this helps.
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