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    Kyle
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    Antique Radio Forums • View topic – 1938 Marconi Model 139 Alignment questions.

    I’m currently trying to figure out how to alignment my radio. I have found a couple of videos on youtube and got a good idea from it. I did a rough alignment just by using a signal generator and sound from the speaker. I do have an oscilloscope but haven’t figure out how to hook it up yet. I went through the alignment and after that I only had one station until I discovered that if I touch tube 6L7 (mixer amplifier) cap wire I get all the local stations loud and clear. What is that telling me? Or, well everything work better if I get a outdoor antenna?

    I could also use some help with the alignment instruction remarks.

    Where its says the afc lead should be attached to the red terminal (B in the wiring diagram pic) osc. section of the gang to be shorted through .1 mfd cap, there was no lead when I restored it. is that the wire coming from r8 and r16 in the pic? And the Osc gang short, do I just short out the osc with the cap to the ground?

    And finally the oscilloscope. connect across load resistor r15. do I connect it after the resister which is connected to ground or before the resistor. And then the ** between the afc wandering lead and chassis.

    Any help would be greatly appreciated. Thanks Kyle.

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