On Mon, 09 Jul 2007 04:49:11 -0700, Telstar Electronics
wrote:

+++On Jul 8, 9:05 pm, Vinnie S. wrote:
+++ I don't think people want to screw with cutting or hacking their radio. I think
+++ you would sell more as an external box. If amplifiers were this way, they would
+++ never sell. That is why people buy them separately, granted, the size would have
+++ some effect. But you can still get stinger boards.
+++ Revisit the idea.
+++
+++There are certainly pros & cons with either approach. One big problem
+++in the external design is the need for a battery. Our feeling was that
+++things with batteries can be problematic... and require additional
+++monitoring to make sure the unit is functioning on a daily basis. This
+++increased "battery vigilance" was one of the main reasons the internal
+++design was chosen. Another issue is definately the radio's internal
+++limiter. On most radios... this is factory set at around 85% possible
+++modulation. If you want to take full advantage of the VoiceMax 100%
+++constant modulation capability... the radios limiter needs to be
+++adjusted/disabled. The VoiceMax has built in limiting... so a
+++redundant system is not needed. However, if the limiter in the set is
+++not adjusted/disabled... VoiceMax will still increase and maintain the
+++modulation to whatever the radio's internal limiter is set to...
+++usally aroud 85% as I said before. It sounds like you have no plans to
+++open your radio... so VoiceMax is not for you.
+++www.telstar-electronics.com
***************

Hogwash and plenty of it.

the SSM2166 draws about 10mA of current. Four NiMH AA batteries have
1800mAhr capabilities. At full charge that delivers 5.6VDC to the
chip. Well within the operating range. Should get about 150 hrs of
operation. Add a charging circuit and you have no more issues.

Yep the internal audio power amp has some form of limiting
(compression) that keeps the modulation percentage in the 85 to 100%
range. Often that feedback path is the first thing that most CBers cut
out when they buy their radios. So what is the need for another
internal compression unit when CBers don't want aduio compression?
Secondly why add another compressor when you already have sufficient
compression built into the radio? If I wanted more, I would increase
the negative feedback to the controlled gain stage of the audio
modualtor section. Often this is just a resistor value change.

Beisdes increasing modulation percentage from 85% to 100% gains little
in range or intelligability. Often not worth the effort. Adds about 7%
audio power into the each of the two sidebands. Even if the limiter
section of the modulator section is not disabled adding your
compressor is not going to increase the percentage of modulation. So
why waste the money to buy and install it unless you disable the
radio's internal limiter?

After doing all that to gain up to 15% increased modulation
percentage? Cheaper to clip and/or alter the feedback in the
modualtion stage.

james