[Boatanchors] Line Voltage issues

[Richard Knoppow]

----- Original Message ----- 
From: "Bill W7KXB" <w7kxb at msn.com>
To: <boatanchors at mailman.qth.net>
Sent: Monday, January 05, 2015 12:19 PM
Subject: [Boatanchors] Line Voltage issues


> A few of us remember when the line voltage was 110 (+/_) 
> (Back when?? )Then the utilities upped it to 115v....then 
> 120v...Now I have 125v.  It's been a gradual increase over 
> several generations. Old gear  is most happy with their 
> specified primary power source of 110 or 115v.  It might 
> tolerate +10%  but not at 120v+ line voltage.       Years 
> ago I changed over to 130V incandescent bulbs because the 
> 125 line was taking out the common 120v variety after a 
> week or so.   By all means do what is necessary to adjust 
> the primary input voltage back down to what ever the 
> manufacture specified at the time.  Then fine tune it for 
> proper filament voltage.  Look for a good ole RMS Line 
> Meter* and a Variac from your favorite ham Swapmeet.  Or 
> check on line for Expanded Scale  Scale (100-140VAC) 
> Voltmeter Kit.
> My 2 cent's worth AR
> de kxBill  .  .

     I don't think there was ever a standardized voltage 
that applied to all areas. Even 60 Hz was not standard in 
all parts of the country, for instance while the City of 
L.A. DWP was 60 Hz some of the smaller companies and So Cal 
Edison were 50 Hz. Burbank and Glendale had 50 Hz power 
until the late 1940s, maybe later. AC voltages were 110, 
115, 117, 120, 124 depending where you were, not including 
the higher voltages for industrial use. There is a tendency 
to increase voltage because of the increased demand. The IR 
loss is less so its cheaper to push up the voltage a little 
rather than use larger wire.  Of course house voltage could 
be brought back down but that would require changing all the 
pole transformers, also expensive.
    I don't think there is a completely satisfactory 
solution to this unless your power company is willing to 
co-operate.  Good voltage regulation can be had by using a 
resonant transformer like a Sola constant voltage 
transformer but they tend to be noisy and are of only 
moderate efficiency, nonetheless the regulation is 
excellent. There are also mechanical regulators. I don't 
know who, if anyone, makes them now but General Radio used 
to make electronically controlled Variacs, not instantaneous 
but very fast and do not waste power or make noise like a 
Sola.  There are probably other ways, a UPS will do it but 
is an expensive way and has a set of vices all its own. For 
a radio set that does not use a lot of power a bucking 
transformer is probably the best way to knock down very high 
line voltages but, of course, it does not regulate.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com