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:Thought that you had that dude in a quasi- operational state ?
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:With initial consideration to be given to the probably ok. . . power supply levels. . . . and then in considering the audio portions of the receiver, would you evaluate that portion in the following manner for me.
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: Almost ZERO requirements, in equipment, although I think ? that I remember you gradually adding onto your test equipment cache. Should the following modulated 455 R.F. signal be needed on the follow up.
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:What you need is a . . .on the safe side. . . .600VDC rated . .. coupling capacitor of a .001 ufd value and two test leads with clip ends.
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:Consult your schematic and note the coupling of the sets low level audio from the detector stage via the item #38 which is an .01 ufd cap.
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:Then have power down and lift one end of that cap. . .the easiest one to do. Then connect a clip lead to one of the plates of one of the #41 AF output tubes (50/50 chance of being right here. . ..phasing considerations) and then the other end of that clip lead gets connected to one lead of that aforementioned .001 cap, with its other lead receiving another test leads clip and then the free test lead clip goes to the high side of the volume control where the other cap . . . .just lifted. . .. .was cutting off the incoming radio audio.
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:NOW if you power up and warm up the set with the volume at its minimum, you should then be able to slowly advance the volume control and find yourself with an audio sweep
:oscillator.
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:That being, from the initial acoustical antics of a cricket ( on steroids) on upwards thru the resonant frequency of the speaker cone and then the cabinet resonance ( if so contained within) up to the point where some of the higher frequencies should drive Aunt Murgatriod out of the guest bedroom. . . in a frenzied state of panic shock.
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:Should the oscillation effect not have occurred, then you need to move that plate lead connection clip over to the OTHER 41’s plate connection.
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:Somewhere within that sweep the audio level should approach the most volume that the set will ever produce. . . .thus confirming adequate current and voltage supply being present for your audio circuitry as well as the audio portion being up to par.
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: Some evaluation of the tone control circuitry can even be made at the higher frequencies by the “colorization” of the tone control, upon the produced signal.
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:Next question. . ..after the mod RF sig generator availability will be if you have . . . ..preferably, one of the OLD generation fluorescent desk lamps with 1-2 small tubes and the “all important” OLD generation common metal ballast transformer.
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:(Also, some aquariums top illumination lamps, are of that category as well as “gro lux” plant lamps, kids older style black light lamps, etc.)
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:The new generation CFL lamps with their “electronic ballasts” are LESS than desirable with their sharp banding of switch mode activity within 60-75-120 khz clusters.
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:Standing by. . . ..
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:73's de Edd
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