On Aug 3, 6:14 pm, "Frank" wrote:
Why are you showing the use of coax to connect the board ? That board has
NO RF filtering and it is NOT shielded in any way. I can imagine what will
happen when it is incorrectly installed in a radio or not shielded with a
filtered supply and filtered input.
It looks like a half finished design. The LED is of no use as that will be
inside the radio and only indicates what the level is at the board - not
what it is on the carrier from the radio. You will also need an
oscilloscope to set it up correctly. I would also be interested in you
telling me how you think the average home user can adjust FM deviation
correctly without the use of a test set!
I wouldn't bother buying one of those, most radios have a better circuit
built in anyway, so having two in series would be of very little use and
would distort the audio or cause extra power consumption in a handheld.
The product is of no use! It would have been good in the 80's before the
K40 and Protel mics were used on CBs. Current CBs and amateur equipment
would not tolerate that circuit as the impedances are completely wrong too.

You haven't researched and appear to have very little working AF/RF
knowledge.

Coax is certainly necessary... and the board is fully shielded. What
do you think that tin plate is for?
The rest of your comments show that you obviously have not read the
installation manual. I suggest you do so at http://www.telstar-electronics.com/VoiceMax%20B.pdf
Thanks for your comments.