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 Grunow 1191

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herromc



Join date : 2017-08-26

PostSubject: Grunow 1191   2017-11-08, 10:53 am

Well, I finally got this radio in good working order.  Recently I had a problem with the potentiometer (vol. too loud), turns out it had a cracked taper.  Luckily I had a spare that worked great.
Now I ran across a small problem with the local radio station frequencies being somewhat off.  Below is an example of what I'm talking about, and as I go up the dial they get further apart.
My question is: What might be causing this, and can it be fixed?  I noticed that on the rear of the chassis (outer) there is an small adjustment screw, but I don't know what it's for.  Anyone know?

Frequency   Comes in at   Off


 860           850             -10
1130          1100            -30
1290          1240            -50
1400          1330            -70
1640          1560            -80
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chas

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Join date : 2017-04-09

PostSubject: Re: Grunow 1191   2017-11-10, 7:05 am

The oscillator is not in alignment.

Need an RF generator, output meter and the alignment instructions.

If the radio will not align there may be a drifted component in the oscillator circuit.

All alignment begins with mechanical setting of the dial indicator at some known marker on the dial at the lowest frequency with the tuning condenser closed.

If there are worn/hard rubber mounts on the tuner that cause a mechanical shift in the dial vs tuner these must be stabilized and centered first, then set for the closed position.

The rear adjustment is an "IF rejector"

See: http://antiqueradios.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=157337

Chas
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herromc



Join date : 2017-08-26

PostSubject: Re: Grunow 1191   2017-11-10, 7:20 am

Thanks for the help!
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Grunow 1191
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