Pi TNC to Motorola Radio


Kevin Reeve
 

Anyone using a Motorola CDM 750, 1550 etc, connected to their Pi TNC through the accessory port on the CDM 750 radio?
The deviation is low even when turning up R7 the audio out pot on the Pi. The goal is a winlink gateway.


Kevin N7RXE




Willem Schreuder
 

On Thu, 30 Aug 2018, Kevin Reeve wrote:

Anyone using a Motorola CDM 750, 1550 etc, connected to their Pi TNC through the accessory port on the CDM 750 radio? The deviation is low even when turning up R7 the audio out pot on the Pi. The goal is a winlink gateway.
Make sure the radio is wideband, not narrow band.

The other trick is to feed the radio on Pin 1 (mic audio) as oppsed to Pin 3 (line audio). The audio on Pin 3 does not get emphasized, which causes problems with decoding.

================================================================
Dr. Willem A. Schreuder, President, Principia Mathematica
Address: 445 Union Blvd, Suite 230, Lakewood, CO 80228, USA
Tel: (303) 716-3573 Fax: (303) 716-3575
WWW: www.prinmath.com Email: Willem.Schreuder@prinmath.com


Teton Amateur Radio Repeater Association (TARRA)
 

You have your pins wrong.

Pin 2 is mic in and pin 5 is Flat TX audio in.

Mick - W7CAT

----- Original Message -----
From: "Willem Schreuder"
To: "RaspberryPi-4-HamRadio@groups.io"
Sent: Thursday, August 30, 2018 11:22:19 AM
Subject: Re: [RaspberryPi-4-HamRadio] Pi TNC to Motorola Radio

> On Thu, 30 Aug 2018, Kevin Reeve wrote:
>
> > Anyone using a Motorola CDM 750, 1550 etc, connected to their Pi TNC
> > through the accessory port on the CDM 750 radio? The deviation is low
> > even when turning up R7 the audio out pot on the Pi. The goal is a
> > winlink gateway.
>
> Make sure the radio is wideband, not narrow band.
>
> The other trick is to feed the radio on Pin 1 (mic audio) as oppsed to Pin
> 3 (line audio). The audio on Pin 3 does not get emphasized, which causes
> problems with decoding.
>
> ================================================================
> Dr. Willem A. Schreuder, President, Principia Mathematica
> Address: 445 Union Blvd, Suite 230, Lakewood, CO 80228, USA
> Tel: (303) 716-3573 Fax: (303) 716-3575
> WWW: www.prinmath.com Email: Willem.Schreuder@...
>
>
>
>

--

Be sure to check out all the latest at our web site!


Willem Schreuder
 

On Thu, 30 Aug 2018, Teton Amateur Radio Repeater Association (TARRA) wrote:

You have your pins wrong.
Pin 2 is mic in and pin 5 is Flat TX audio in.
Oops, sorry you are right (I was looking at it upside down).

With that correction, the point is still to feed via the mic, not line/flat.

================================================================
Dr. Willem A. Schreuder, President, Principia Mathematica
Address: 445 Union Blvd, Suite 230, Lakewood, CO 80228, USA
Tel: (303) 716-3573 Fax: (303) 716-3575
WWW: www.prinmath.com Email: Willem.Schreuder@prinmath.com


Teton Amateur Radio Repeater Association (TARRA)
 

It wouldn't be the first time I did something upside down or backwards : )

Mick - W7CAT

----- Original Message -----
From: "Willem Schreuder"
To: RaspberryPi-4-HamRadio@groups.io
Sent: Thursday, August 30, 2018 11:34:14 AM
Subject: Re: [RaspberryPi-4-HamRadio] Pi TNC to Motorola Radio

> On Thu, 30 Aug 2018, Teton Amateur Radio Repeater Association (TARRA) wrote:
>
> > You have your pins wrong.
> > Pin 2 is mic in and pin 5 is Flat TX audio in.
>
> Oops, sorry you are right (I was looking at it upside down).
>
> With that correction, the point is still to feed via the mic, not
> line/flat.
>
> ================================================================
> Dr. Willem A. Schreuder, President, Principia Mathematica
> Address: 445 Union Blvd, Suite 230, Lakewood, CO 80228, USA
> Tel: (303) 716-3573 Fax: (303) 716-3575
> WWW: www.prinmath.com Email: Willem.Schreuder@...
>
>
>
>

--

Be sure to check out all the latest at our web site!


Kevin Reeve
 

Thanks,

 

Radio in wideband mode but most likely feeding the flat audio in pin. 

Kevin

 

 

From: <RaspberryPi-4-HamRadio@groups.io> on behalf of "Teton Amateur Radio Repeater Association (TARRA)" <tarra@...>
Reply-To: "RaspberryPi-4-HamRadio@groups.io" <RaspberryPi-4-HamRadio@groups.io>
Date: Thursday, August 30, 2018 at 11:45 AM
To: "RaspberryPi-4-HamRadio@groups.io" <RaspberryPi-4-HamRadio@groups.io>
Subject: Re: [RaspberryPi-4-HamRadio] Pi TNC to Motorola Radio

 

It wouldn't be the first time I did something upside down or backwards : )

Mick - W7CAT

----- Original Message -----
From: "Willem Schreuder"
To: RaspberryPi-4-HamRadio@groups.io
Sent: Thursday, August 30, 2018 11:34:14 AM
Subject: Re: [RaspberryPi-4-HamRadio] Pi TNC to Motorola Radio

> On Thu, 30 Aug 2018, Teton Amateur Radio Repeater Association (TARRA) wrote:
>
> > You have your pins wrong.
> > Pin 2 is mic in and pin 5 is Flat TX audio in.
>
> Oops, sorry you are right (I was looking at it upside down).
>
> With that correction, the point is still to feed via the mic, not
> line/flat.
>
> ================================================================
> Dr. Willem A. Schreuder, President, Principia Mathematica
> Address: 445 Union Blvd, Suite 230, Lakewood, CO 80228, USA
> Tel: (303) 716-3573 Fax: (303) 716-3575
> WWW: www.prinmath.com Email: Willem.Schreuder@...
>
>
>
>

--

Be sure to check out all the latest at our web site!