Voltage question

you need the STD

Nope
Don't need any STD thanks.
You keep them to yourself please!

thanks everyone for your input. If I do pursue this I will definitely step down the voltage, hopefully avoiding STD  s....

@winoguy17 

Just to be clear, you need to select a step down transformer (SDT) that best matches your wall AC mains voltage. Again you need to check your AC mains voltage at the wall outlet.
 
If your mains voltage average is 120Vac or less then a 115-120Vac to 100V SDT would average an output closest to 100Vac.     
Example  
  https://www.bhphotovideo.com/c/product/964851-REG/acupwr_ajd_300_ctoc_japan_to.html.      
If the wall outlet mains voltage is higher than 120V, say 122V, then a 115-120Vac to 100Vac SDT would not be a good choice, imo.  The output voltage of the SDT would be higher than 100Vac.

 
 If the mains voltage averages higher than 120V, say 122V, maybe 123V, then the  125Vac to 100Vac SDT would be a better choice. The average output voltage of the SDT would be closer to 100Vac.      
 Example         
https://acupwr.com/collections/japan-to-usa-transformer-converter-use-100-volt-appliances-in-110-vol...  


If you can find a SDT that is rated at *120Vac* to 100Vac that would be fine for a mains voltage that ranges from 118Vac - 122Vac.  
If the mains voltage is below 120Vac then the SDT would output slightly below 100Vac. With a mains voltage above 120V the SDT output voltage would be slightly above 100Vac.

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