> From: DANMAS@aol.com
> Date: Fri, 29 Aug 1997 09:04:46 -0400 (EDT)
> To: gardner@lwcomm.com, mgs@autox.team.net
> Subject: Re: Stereo contacts in doorjamb.
> In a message dated 97-08-29 05:13:55 EDT, gardner@lwcomm.com writes:
>
> > If it were a problem, stereo
> > manuals would warn against playing the radio for long periods of time
> > with the BALANCE knob all the way to one side, and I've never seen a
> > warning like that.
>
> Scott:
>
> The balance control works on a completely different principle - it is placed
> between the inout and the output stages, and varies the INPUT signal to the
> output stages. The output transisters still see the 8 ohm load of the
> speakers. The add-on fader units that are placed in the output between the
> speakers are designed such that impedance seen by the radio remains constant.
> That is, as it turns down the speaker impedance seen by the radio, it turns
> up the resistance of the fader such that the radio always sees a constant
> impedance. The output power is either spent in the speakers or in the fader
> resistance. That's why faders are not available for high power units - the
> wasted output heats them up.
>
> Many of the older radios will indeed be damaged by operating without a
> speaker connected. Most of the newer unit do not have this problem. It would
> be advisable to check the instruction manual with the unit you are using
> before installing the jamb switches.
>
> Dan Masters,
> Alcoa, TN
>
Dan,
Jeez, I dropped the ball on that one. You're absolutley right, and
I should really stop composing letters in the wee hours of the
morning. You wouldn't know I was first in my class in
Navy Electronics tech "A" school from my response, would you? Just
forget I ever said anything on the topic of mismatched amplifier
loads, and I'll commence to whapping myself in the face with a large
book as soon as I'm offline.
Sheepishly yours,
Scott Gardner
Scott Gardner
gardner@lwcomm.com
www.lwcomm.com/~gardner
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