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useing a Variac to test radio
#1

How would you use variac to test a radio so as to be safer than putting full voltage to the set. I understand if you make up a tester as I saw where you have light bulbs so if a 30 watt light bulb doesnt light it shows thee is a problewm, etc. But, when useing a variac do you just watch while uping the voltage to see if it smokes, etc? Sounds like by the time it smokes or something you already have ruined something anyway. Can someone explain the steps used so nothing hurts the radio, or am I right in assuming you just wztch it while turnin gup voltage. Thanks for any info on the subject.
#2

Hi All;
Warren, I would not just up the voltage just to see if something smokes..
When, I use my Variac, for the first time on something, I also put in the Dim bulb as well.. Also, I would with each upping check the different voltages, to see if they look like they are in the appropiate ball park of what I would expect.. I start at about 40% and check my filament voltages and B+ voltages, the got to 60% things should have a readable value by then.. then upping 10% at a time untill I get to 100% then by 5% untill It reaches about 115%.. By that time all readings should be in the range of what I would expect from the schematic.. If things look ok by that time and nothing is way off, then I can remove the bulb.. And only use the Variac.. But, If at any time things are not looking right or correct I would immediately shut things OFF.. And Investigate what is wrong..
THANK YOU Marty
#3

Ahhh, that makes sense. Thanks for the reply. I have a variac but didn't want to just up the voltages without some kind of plan on how to check things. Looks like I should build the light thing to check with also. Thanks, again. Warren




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