Batboard

Greetings all!

We are looking to add an external wall speaker that has a built in volume control to our digital scanner, so we can hear the unit in our crew room.

Currently, we are only looking to add one speaker, so I was trying to shy away from using an amplifier and associated speakers. However I am open to any sugestions people may have!

Thanks!

-Eric

Eric,

The most practical way to do this, assuming the receiver has
enough spare audio power, is to do it right the first time, so what
you could do is this:

1. Put in a transformer to convert the 8 ohms to 70 volts.
2. Install a wall-mounted Atlas level control. People think
these are pots but they're actually tapped transformers.
3. Install a 70 volt to 8 ohm transformer in the speaker cabinet.
4. Use an eight-inch speaker mounted in one of those common
angled wall cabinets to cover the area.
5. If/when a second speaker is needed you just add another
speaker and transformer and wire it from the first location.

Regards,

Or a Valcom Wall/Ceiling Speaker, Surface or flush mount. Just needs a 24VDC wall wart. I use them on MCS2ks fed by pin 11. Does the job.

Anyone know of a good source for any of these items? Or what specific terms/requirements I should look out for?

It would just simply be driven from a Uniden Scanner.

I'd start by Googling Valcom PA's and see what pops up. Fire Alarm companies use them for their PA's as does Telco outfits.
There are several flavours and types to choose from. In ceiling tiles or in the wall or hang on the wall, Big or little. They incorporate an amp that takes -20 dB or less or way more and will boost it up to a couple of Watts. Most come with a knob that can be removed if needed. Your scanner unit should have an audio output jack of some sort to feed it with. A 24 VDC wall wart will do quite nicely to power it. Standard Telco quad wire will suffice to wire it.
I put two in a boardroom ceiling and drive them from the AF output of the projector unit. Produces theater sound!

Can't you just use the...... oh wait, never mind. They haven't figured out how to make a hybrid Astro/Analog station alert yet.

If you plug into the speaker jack on most scanners it will disable the internal speaker, if this is not what you want you will need another speaker for the room the scanner is in or will have to open the scanner up and tap the speaker wires to drive the external speaker.

EOppegaard wrote:We are looking to add an external wall speaker that has a built in volume control to our digital scanner, so we can hear the unit in our crew room.

I would second the vote for using valcom self amplifed speakers. The also make a very nice local volume control that mounts in a mud ring or standard wall box. http://www.valcom.com/. If the scanner audio out mutes the internal speaker, deploy another Valcom unit adjacent to the scanner.

Ray Vaughan, KD4BBM has this system installed in a fire house in FL http://rayvaughan.com/recall.htm

nmfire10 wrote:Can't you just use the...... oh wait, never mind. They haven't figured out how to make a hybrid Astro/Analog station alert yet.

Yeah, thanks...

Currently the Uniden 996T scanner is hooked up to a computer that records the output, as well as the front speaker is still enabled.

It has both a record, and a scan output. We want to add in the ability to stream it over the internet, so I guess it will be simply another splitter off the record...not a big deal.

With the Valcom units, all I need is the speaker, linear power supply, and output, correct?

if we are looking to eventually expand the system, which unit should we look at? http://valcom.com/linear.htm

Yes - I had a few problems with the switching power supplies, absouletly none with the linear.

I agree with the linear.

i am looking to feed audio into our bay's using the pin-out on a motorola cdm-1550.
i got it working well, but i need a way i can regulate the speaker volume so it is lower than the built-in speaker.
(Neighbors complain it's too loud).

I'm just thinking of putting a volume control (from radio shack) into the speaker line (like one of those wall mounted volume controls, except i wouldn't install it into the wall.)

Any suggestions?
-Parker