"Found this neat product and thought I would spread the word.
This is a quick review I just made on the unit.

Just received my Naval Electronics HTS-3 Audio Booster battery powered
amplified speaker in the mail. I couldn't wait to hook it up. I wasn't too
sure how the sound was going to be considering it's compact size. Finally
got the box open and was really surprised at the completeness of the
package. More than enough connecting cables(cigar lighter adapter for
12Vdc use,mono to stereo 1/8",and tape record 1/8" to 3/32")and adapters
were included. This unit also has the capability to turn a recorder on and
off automatically with the supplied cables although I did not test this
feature. A thorough instruction manual was included (4 pages).Upon close
examination I found the speaker was actually ported just like your home
stereo ones are. After loading the battery case(4 "AA"s) and plugging it
into my HT I was really surprised at the amplification and sound quality.
I knew right away this was just what I needed for my high noise
environment listening(airport maintenance hangar). This unit even has a
gain adjustment pot hidden in the battery compartment for that just right
sound level while minimizing hiss. Also found a feature that works great
and that is the ability to use the speaker even when the batteries die.
Just flip the switch off and it feeds the speaker directly. This unit even
has a power on LED to let you know it's powered on. Nice! I found one
little problem and that was a little annoying vibration inside the unit
when the speaker was cranked up. I went ahead and opened the unit up and
found the wiring to the speaker to be loose inside and the LED lead to be
bent over touching the speaker frame(which I might add is a very sizable
one with a substantial magnet.) A little tape on the loose wiring and a
slight tug on the LED lead and reassembly of the unit proved fruitful. No
more vibration. Not too sure if this is a common problem but I am sure
Naval Electronics would make it right if you had experienced this problem.
Another feature of this unit is even if you let it sit idle for months
turned on it has an auto-sleep feature that shuts down the amplification
thereby conserving your battery(manual says up to 3 months). I am planning
on buying several more of these.They really transform the sound of an HT.
This is just what you need to boost that HT or scanner's audio with the
problem of small inefficient speakers which are all too common nowadays.

See their website:   http://www.naval.com/hts-3/

Eddie Bryant  N4UMJ "