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The ballast resistor on those cars was a piece of "resistance wire" of the exact same type as on the cords of the "curtain burner" radios of the mid to late 1930s . The wire would outwardly appear as a normal wire , but when cut into was revealed to be a finely wound coil of wire under that insulation , and thus a "wired in" ballast resistor was provided . truth be told , in my days of yore working on cars , I only ran into a couple of Fords with an open ballast wire , VS literally DOZENS of failed Plymouth ceramic block style ones . Classic symptom was , car would start and run as long as the key was in the start position , but when let to return to the Run position after starting , the engine would instantly quit (as the boost 12 volts went away and the ballast wasn't there to provide the running voltage) |
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__________________
Yes you can call me "Squirrel boy" |
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Hi Squirrel Guy ,
When the manufacturers were first attempting transformer less radios , the tubes such as 50L6 and 35Z5 didn't exist yet . They had mostly 25 volt heater types such as the type 43 which was an output tube and the 25Z6 for a voltage doubling rectifier . Now , in the later "All American Five" sets , using 50L6 , 35Z5 , 12SA7 , 12SK7 , and 12SQ7 , the sum of the voltage drawn by the series connected heaters was 121 volts , just perfect for our 120 volt wall outlets . But the older , 25 volt heater tubes , usually used with 6 volt heater types such as 6A7 , 6K7 , 6Q7 , and then 43 and the 25Z6 only added up to 67 volts in series and thus needed some means of dropping the additional line voltage . Some sets used ballast resistors that looked somewhat like tubes , and some used a piece of resistance wire in the line cord to drop the difference and allow the tubes to draw their 67 volts . The cord would have three wires , one all of it's own to be one side of the line , one on the other side of the line that fed directly to the rectifier's plate , and the third one which was the resistance wire coming from the same plug blade as the one for the rectifier's plate . To most old radio guys , the term "curtain burner" refers ONLY to sets with the dropping resistance in the line cord , but some folks mistakenly seem to call ANY "AA5" set a curtain burner even the later ones with no dropping resistance needed at all . Funny thing about the tube type ballasts was , that certain manufacturers got caught lying and calling them tubes (as in active receiving elements , not just glorified "dim bulbs" which the tubular ballasts were) and got in legal trouble over it . When tube count reigned supreme in the choice of which radio to buy , and one could easily up the tube count by a few by using some glass encased resistors , whose gonna notice , right ? Well , the other manufacturers who weren't falsely inflating their tube counts let the Govt in on the secret and a few went out of business . Ya mean our generation DIDN'T invent corporate greed ? |
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