Custom Products for the Digital Radio Amateur Enthusiast

Differences between the DRA-45 and DRA-65:

Some applications like VARA FM and SoundModem have been rewritten to assert GPIO3 on the CM119A like AllStar Link does. This GPIO biases a 2N2222 that's used to key the radio set. However, some digital applications don't yet have that ability. WSJT-X is one that currently doesn't. For those that don't - - VOX is available. As long as the application duplicates the audio on both Left and Right audio channels, one channel is used to feed the VOX, while the other is used to feed the transmitter. Since both channels have independent level controls (pots) the audio level feeding the VOX can be set where it reliably creates a PTT, while the other channel can be set to properly drive the transmitter. The VOX takes LOTS of audio, so Windows volume is generally up pretty high and so is the pot feeding the VOX circuitry. The other transmit channel is then set where it needs to be without over-driving the MIC or modulator. The DRA-65 and '70 have headers to configure which channel drives the VOX, so the opposite channel can drive the transmitter.

The DRA-70 is basically the same as a DRA-65, but with a Mini-DIN-6 replacing the DB9 radio connector.

Parts List:
If you purchased our kit, refer to the parts list and make sure you have all of the components you need to build it.
Click here for Parts List.

Construction/Assembly:
Click here for assembly instructions and construction notes - with large photos.

Jumper Settings:
Click here for Jumper Settings and other board connection assignments.

DB9 Pinout:
Click here for DB9 Pinout.

Installation:
This device is intended to be installed inside a radio, computer, or project box for protection. Refer to the schematic for the pinout of the DB9F where all of the logic signals, power connections, and audio signals are listed.

H1 and H2 header pin assignments:
Click here for a detailed header pin explanation. The primary purpose of the headers H1 and H2 are for installation of optional FL-10 audio filters. The FL-10 is designed to be installed onto the header pins directly or remotely by extending the four pins with wires. Jumpers are needed over the center two pins if the optional filters are not installed.

Recommended powering requirements:
The board is supplied with 5 VDC from the USB connection. The audio amplifiers and optional filters can run from this, or from an external power source of 6 to 15 VDC. Jumper JU2 controls where the voltage is sourced from.

Recommended receive audio input level:
The DRA-65 accepts the widest range of audio compared to any other similar radio adapter. The input signal is attenuated by a potentiometer, giving the broadest range of acceptable levels. As little as 20 mV P-P, and as much as 20 volts P-P. If your receive audio level is adjustable or programmable, we recommend around 2.0 volts P-P. This allows very good signal-to-noise ratio and low cabling cross talk. This level results in a 50% rotational setting of the potentiometer.

Optional Plastic Case:
A Plastic Case is available optionally for the DRA-65. Available in several colors!

All DRA-65's are supplied with a Genuine C-Media CM119A, but the DRA-65 board was designed to be versatile. It will accept a CM119 (without the A) and even the CM108. There are slight differences between these components, and the board can be 'programmed' to accept any of the three.

Information on the CM119A.
Click here to download a manual for the C-Media CM119A.

Secure PayPal ordering is available from the DRA-65 main page.

Custom cables available from URI Cables. They will build a custom cable for the DRA-65 for many radios.

Email Kevin Custer for support, ordering information, order by check, and/or support of this exciting product.
 
 

Product of Masters Communications, all rights reserved.
Specifications may change without notice.
Images property of Kevin Custer - W3KKC
Board layout by Kevin Custer - W3KKC.
HTML March 10, 2020, W3KKC All Rights Reserved!