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Old 25th Feb 2021, 5:43 pm   #1
BrianAllen
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Default HMV 1120 Exceptional MW no LW

I have just replaced a few caps and now have exceptional MW signal but no LW; any ideas where to start searching for the problem please.

There was no LW reception prior to changing the caps.

Thank you.
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Old 25th Feb 2021, 6:36 pm   #2
vinrads
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Default Re: HMV 1120 Exceptional MW no LW

Check if the osc is running first , do you have a scope , or if I remember correctly meter the cathode of the osc valve short the ocs tuning capacitor to chassis , the volts should increase if it's oscillating , Mick.
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Old 25th Feb 2021, 9:27 pm   #3
BrianAllen
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Default Re: HMV 1120 Exceptional MW no LW

Thanks Mick, yes I have a scope but as yet have not familiarised myself as to how to operate but will do as you suggest.

Thank you.
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Old 25th Feb 2021, 9:55 pm   #4
vinrads
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Default Re: HMV 1120 Exceptional MW no LW

Hi Brian ,time to get familiar with the scope ,switch to mw , try and find a sinewave on one of the sections on the tuning capacitor , it will vary with the tuning , then switch to l/w and see if you have a waveform on the same part of the tuning capacitor ,hope this makes sense, Mick.
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Old 1st Mar 2021, 7:46 pm   #5
BrianAllen
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Default Re: HMV 1120 Exceptional MW no LW

Yes, all makes sense Mick, will give it a try after getting used to scope.

Thank you.
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