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Larry W4CSC
 
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Default Ext spkr for VHF Radio

As long as both radio and stereo use battery negative for one side of
the audio output, this arrangement will work just fine. Use an
ohmmeter and measure from battery negative to the "speaker common" on
both units. If they're both connected to battery negative (ground?),
your connections are fine.



On Sat, 20 Dec 2003 23:30:12 -0800, "Bill Andersen"
wrote:

The switch I bought is called DPDT. It has six posts: 2 left, 2 center, 2
right.
I intended to use the two on the left side for the left and right stereo
channels and the two on the right side for the VHF (jumpered to both posts).
The center posts are for the grounds of both speakers.
I know I can add a separate speaker for the VHF radio. My idea was to use
the existing stereo speakers for the VHF radio with the option of switching
them back to the stereo.
I sometimes place my hand held radio in a holder mounted on the engine
compartment. That's OK, but uses up the batteries.


"Larry W4CSC" wrote in message
...
You need a 4-pole switch to be safe. Switch BOTH wires on BOTH
speakers, not just the hot lead. Not all amps use ground (negative
battery) for their return wires.



On Thu, 18 Dec 2003 22:13:52 -0800, "Bill Andersen"
wrote:

...in parallel.. I'm trying to remember what that is.
But, only one radio powers the speakers at a time, that's why I used a

DPDT
switch.
Bill
"Larry W4CSC" wrote in message
...
NEVER, EVER HOOK TWO TRANSISTOR POWER AMPLIFIERS IN PARALLEL!
Never wire one device to the same speakers as another. One device is
a virtual short to the other and may even present battery voltage to
the other, blowing the hell out of both! It may have already
happened, I can't say from here.

When my SECOND unprotected cheap Sea Ray AM/FM/cassette player croaked
from the salt spray on it, it tore it all out and mounted my Icom M59
in its hole. The Icom now powers BOTH "marine speakers" hooked simply
in parallel in the cockpit. Works great, plenty of volume.....

You may blow the amps hooking them in parallel......not good.



On Thu, 18 Dec 2003 08:50:30 -0800, "Bill Andersen"
wrote:

I want to use the two stereo speakers of my boats AM/FM/Cassette

Player
for
my VHF radio. I wired both radios to a Double Pole Double Throw

switch.
The
AM/FM/Cassette Player works, but the VHF radio volume is so low I can
barely
hear it.
The specifications for both radios state 4-8 ohm speakers. The
AM/FM/Cassette Player states 14 watts RMS maximum stereo power, the

VHF
radio states 4 watts audio output.
Is there anyway I can use the stereo speakers for both radios? If not,
will
the VHF radio have enough power to hear it if I add two of the
mini-speakers
designed for it in the rear cockpit area?



Larry W4CSC

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Larry W4CSC

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Larry W4CSC

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