37-116x, Disconnecting the Speaker during alignment? - Printable Version

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+--- Thread: 37-116x, Disconnecting the Speaker during alignment? (/showthread.php?tid=2505)

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37-116x, Disconnecting the Speaker during alignment? - spfradios2 - 07-25-2010

My 116 is ready for alignment. I've done several, so I'm confident about the process. However, I have never "disconnected" the speaker during an alignment. Things get pretty loud. Somewhere I've come across the idea in my reading, but I don't recall what to do.

At what point could you disconnect the speaker? At the voice coil?, Output transformer primary?? Would you install a resistor as a replacement load?

Any info welcome. Thanks in advance.

John

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Re: 37-116x, Disconnecting the Speaker during alignment? - Ron Ramirez - 07-25-2010

Hi

You don't disconnect the speaker.

If you can, connect your output meter or oscilloscope across the plates of the audio output tubes. Turn the volume up, feed as low a signal in as you can. This will also keep the AVC from acting too strongly on your signal.

The trick here is to use the lowest possible signal into the radio, which will result in a more accurate alignment.

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Re: 37-116x, Disconnecting the Speaker during alignment? - exray - 07-25-2010

Use the AVC line. They didn't often recommend that in the old days because many service shops would not have had a suitable meter.

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