I heard my amp can kill me because it doesn't
have
a power transformer! Why?
I've ordered "Sprague TVA Atom" capacitors
(either
from us or other places), some are labelled "Sprague" , others
"Chemicon",
even tho the part numbers are the same. What gives? Which are yours?
Some of your sockets are labelled "Amphenol
Made By WPI". Are these real Amphenols? Are they really made in USA?
What is a "cookie" being used for on your online
ordering page?
What's my amp (preamp, tuner, etc.) worth?
Did Raymond Loewy really design the Coca Cola
bottle?
Was O'Hare Airport
named after Al Capone's lawyer?
Q.I heard my amp can kill me because it doesn't have a power transformer! Why?
Back in the old days, many cheap entry level tube amplifiers did not
use power transformers. These usually can be identified by the presence
of certain tubes (50C5 ,50L6, 35C5 and 35L6 are typical output tubes,
35Z5
or 35W4 are typical rectifier tubes), and because you can see only one
small transformer (none if it's under the chassis), sometimes mounted
on
the speaker.The lack of a power transformer means that the ground side
of the amplifier is actually the low side of the AC power line coming
out
of your wall!...and it might not be the low side, because some of these
old amps didn't have "polarized" plugs that keep you from plugging in
the
plug the wrong way, and it's not impossible (especially in older
places)
for the sockets to be wired wrong, too.
Because of the way guitar pickups and microphones work, they require
an AC signal ground return. To keep you from getting shocked (or to put
it more accurately, so you'd only get shocked mildly) in the case of a
reversed ground, these amps typically used a resistor paralleled with a
capacitor (typically a .047 bypassed by a 220K resistor) between the
ground
side of the input and the actual circuit ground...basically, just
enough
impedance to block big medicine juice coming out of the wall, but not
enough
to block the small signal coming from a guitar or microphone. Unlike
the
"ground polarity" capacitors found in some amps, like old Fenders, this
resistor/capacitor combination cannot be removed as the input
will
not work at all without it.
The real problems with these amplifiers are (1) the small capacitor
(especially old wax ones made before the early 1960's) can short out
and
could put live,direct AC wall juice right on your guitar or
microphone.This
can and has killed people.(2) Many of these amps do not have fuses, and
if something in your amp shorts out, it could be a smoking ball of
flame
and start a house fire before it blows your house fuse or circuit
breaker.
This has killed even more people than the previous case.
The solutions are pretty simple:
1.Replace the offending capacitor. The best one to use is a
125VAC UL rated line filter cap, but a new 600VDC rated capacitor is
still
a lot better that what came in these originally.
Many of these old amps need other capacitors replaced just as routine
maintainence, there's generally only a few dollars worth of capacitors
in these amplifiers. When electrolytics go bad, either the amp will
start
humming uncontrollably or the capacitor will spew corrosive goo inside
the amp, which is a mess to clean up.
2.Use an isolation transformer.We sell these, including stepdown
versions that allow these amps to be used on 230V European voltages.
This
is highly recommended if you are going to use the amp for gigging
or
recording, namely, anywhere you might be touching another piece of
equipment at the same time you are using it.
3. Install a fuse.If you don't want to poke a hole in the amp
to mount a conventional fuseholder, inline fuseholders with wire leads
that can be installed inside the amp can be had at nearly any auto
parts
store. The usual 3 tube or 2 tube guitar amp needs a 1/2 amp
slowblow
fuse.
Some old "hifi" amps (mainly pulled from old consoles), have "transformerless" amplifiers as well. These have the same dangers as guitar amplifiers, usually there's RCA input jacks grounded in the same manner as the input jacks in guitar amps. Trying to interface this type of amplifier with modern day or other transformer isolated equipment without using an isolation transformer is problematical, possibly dangerous, especially if there's no fuse and the "isolation" capacitor is toasted.
A lot of old radios &TV's are "transformerless", these usually isolated the user with plenty of plastic or wood and often had "interlock" plugs that disconnected the AC power if the back was removed.Still, replacing that "isolation" capacitor to the chassis and installing a fuse is a very good idea if you wish to use this type of equipment.
Q.I've ordered "Sprague TVA Atom"
capacitors
(either from us or other places), some are labelled
"Sprague" , others "Chemicon", even tho the part numbers are the
same. What gives? Which are yours?
A.TVA "Atom" electrolytics have been made for a number of years
under
contract for Sprague/Vishay by United Chemicon in North Carolina.
Provided
the part numbers are the same, they're exactly the same item.
Q.Some of your sockets & plugs are labelled "Amphenol Made By WPI". Are these real Amphenols? Are they really made in USA?
A.Some time back Amphenol, (formerly American Phenolic Co) sold the
tooling for manufacture of their 4, 5, 6, 8(Octal) and 11 pin sockets
&
plugs to Wire Pro, Inc. , who manufactures these under license.
These are exactly the same as the Amphenol parts and in most cases
are still stamped "Amphenol".
Q.What is a "cookie" being used for on your online ordering page?
A. The "cookie" is solely used for keeping track of what's in your
"shopping
basket". For example,if you lose your connection, you can come back and
pick up shopping where you left off. The cookie does not track or
contain any personal information other than your shopping basket
contents. If you block the cookie, the shopping basket won't work.
Q. Did Raymond Loewy really design the Coca Cola bottle?
The Encyclopaedia Britannica
says so, and Loewy's own web site
says so, but, no he didn't. The Coca Cola bottle was designed (and
patented,
thus leaving no doubt as to the date) in 1915 by the Root Glass Co. of
Terre Haute, Indiana. Oddly enough, one of the fellows who really did
design
the bottle (T. Clyde Edwards ) based it on a drawing of a cocoa (not
coca
or cola) bean pod drawing in a copy of the Encyclopaedia Britannica,
which
nowadays incorrectly credits Loewy, as this
web page at Indiana State University relates.Coca Cola themselves
verify
this story, and they own the original prototype.
Loewy was no doubt a genius and designed a great number of important
and distinctive industrial products, including Coca-Cola vending
machines, and he he did
at one time comment that the Coke bottle was a brilliant design, but he
didn't design THE Coke bottle, as in 1915 he was either still in school
in France or serving in the French Army. Loewy didn't emigrate to the
USA
until 1919. Also see this
page on Urban Legends about the Coke bottle.
Q. Was O'Hare
Airport named after Al Capone's lawyer?
Almost. It was named "Butch" O'Hare, a World War 2 pilot and
posthumous Medal Of Honor winner, who was also the son of an Eddie
O'Hare, a lawyer & business associate of Al Capone. Here's
da facts.