Article View: sci.electronics
Article #17575Re: need advice on TV sound amplifier
From: lacasse
Date: Wed, 06 May 1987 01:54
Date: Wed, 06 May 1987 01:54
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One person asked for help where the sound level in the headphones plugged
into a TV for a hard-of-hearing person was insufficient when the volumn
control was set at a confortable level for other viewers to listen on
the still-connected speaker.
Someone replied and suggested attenuating the speaker inside the set.
He cautioned of electrocution and other risks of altering the set.
I re-iterate his caution: don't modify a TV set if you are not "qualified
service personnel".
But it is interesting to note that many TV sets have a resistor in
series with the headphone jack to attenuate it. I suspect they do this
to make the volumn control more usefull for the headphone listener.
Since in your set the speaker does not cut off when a headphone plug
is inserted (most do), the manufacture may also attenuate the headphone
plug in the hope of making the speaker and headphone level more
commenserate. In general, a headphone takes a LOT less power then
a speaker. If your set has such a resistor, you might be better off
it if wasn't there (shorted out). Then you could use a simple "L-PAD"
(100 ohm 5 watt potentiometer) in series with the headphone, near
the headphone, adjusted by the hard-of-hearing person. You might
want to take your TV to a good repair center and ask if this modification
could be made.
mark
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!utgpu!water!watmath!clyde!rutgers!ames!ucbcad!ucbvax!decvax!decwrl!hplabs!sdcrdcf!randvax!lacasse From: lacasse@randvax.UUCP Newsgroups: sci.electronics Subject: Re: need advice on TV sound amplifier Message-ID: <966@randvax.UUCP> Date: Tue, 5-May-87 21:54:33 EDT Article-I.D.: randvax.966 Posted: Tue May 5 21:54:33 1987 Date-Received: Fri, 8-May-87 03:57:04 EDT References: <578@stracs.cs.strath.ac.uk> <566@neoucom.UUCP> <1272@genrad.UUCP> Reply-To: lacasse@rand-unix.UUCP (Mark LaCasse) Organization: Rand Corp., Santa Monica Lines: 26