[GreenKeys] Model 28 signal lines

[ken Schwieker]

I haven't seen this mentioned but if it has disregard this. Many 
power transformers have a dual primary
for use with either 120v or 240v. Many are available fairly cheaply 
from surplus outlets or may be found when scrapping equipment. Use 
one of the winding
for the primary and the other for the isolated secondary. Another 
option is if original output of the transformer was a low voltage 
then that winding can be connected
in series opposing with the now secondary to lower the ac output to a 
point where the resultant rectified and filtered DC out would
be lower than the165v DC you would get starting with 120v AC to 
rectifier. Less heat dissipated in loop resistor and somewhat lower 
shock hazzard.

Ken S



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