[TenTec] Using a Yamaha CM500 headset with TT Orion II - advice needed!

[Barry N1EU]

Steve, the Orion II has an internal 2.2K resistor in series with +10V/pin2

Schematic is viewable at
http://www.tentecwiki.org/webarchive/566/schematics/566KEYPAD.PDF

73, Barry N1EU

On Wed, Apr 8, 2015 at 5:22 AM, Steve Ireland <vk6vz at arach.net.au> wrote:

> G’day
>
> I have been trying to use a Yamaha CM500 headset with my TT Orion II and
> have been having a few issues in getting levels right in the Orion with the
> electret mic.  Please, if anyone is using a similar set-up and are happy
> with the results, I’d really like to know:
>   a.. what is used in the way of a resistor/pad between the 10V output
> from the TT Orion mic socket and the 3V CM500 electret bias?
>   b.. what is used (if any) in the way of a pad to reduce the output of
> the electret mic?
>   c.. what setting is used on the MIC gain (i.e. the DSP mic gain, set
> using the MIC button and the MULTI pot)?
>   d.. what dB setting is used on the H/W mic gain (i.e. the hardware mic
> gain, set using SSB menu function)?
> At present I am using two 2.2K in series as a voltage divider to reduce
> the 10V bias to around half (i.e. 5V), and then reducing the electret mic
> output by a voltage divider using a 430 ohm resistor in series with a 220
> ohm resistor and taking the output from the top of the 220 ohm. I also have
> a 4.7uF electrolytic in series with the electret mic output voltage divider
> so as to block any DC potential (to be sure, to be sure) coming from the
> electric mic element back into the TT Orion mic audio input.
>
> My current set-up isn’t working (sounding) well and the best thing seemed
> to be to ask for some advice.
>
> Vy 73
>
> Steve, VK6VZ
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> http://www.avast.com
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>