Custom Products for the Digital Radio Amateur Enthusiast

Prior to purchase DRA Support Information:

Start Here:
A list of data capable radios that have a dedicated Mini-DIN-6 data port.
An article to help determine which DRA might be best for you if you own one of these radios.

Which DRA should I buy - I don't have a data ready radio?
If your radio isn't listed in the article above, go here to help make a decision.

Ordering Information for our products.
How to order products from Masters Communications and what to expect shipping wise.

Support Documentation - Availability of schematics, jumper settings, radio connector pinouts and all support documentation for DRA Products.
I don't require a purchase to have free access to support information. Go here to understand how to access the information.
Owners Manuals are created by printing the information available here.

A statement about DRA quality. - An opinion on what is truly state of the art, and how our products are designed and built.

DRA-Sound-Cards Group
A free support group at IO for the DRA-Series sound card interfaces.

DRA Hardware Specific Support Information:

Hardware PTT for C-Media GPIO
Everyone should read this explaination of the push-to-talk operation on the DRA Series radio adapter interfaces.

Initial DRA Start-Up
Basic operation and some steps for testing the unit after buying or building.

Setting Audio Levels
A guide to setting audio levels when you don't have access to professional test equipment.

Cables for DRA (sound card) Products
What radio cables are needed for the DRA products from Masters Communications.

Receiver Baud Rate Selection.
Understanding how RX baud rates are selected.

Help! - my transmit levels keep changing on their own.
A help article to understand how volume levels can change becuase of hardware and wiring situations.

What baud (transfer) rate is my radio and DRA capable of?
Understanding how fast the data transfer rates can be.

Frequency response of the DRA Series radio interfaces.
Understanding how and why these interfaces are built, and the resulting frequency response and other performance references.

Differences between the RA and DRA Series
What makes these two series different, and some history!

VOX Operation Information:

VOX Operation on the DRA-65, DRA-70, and DRA-80
Understanding how to use the VOX on these DRA's

MMSSTV VOX Operation on the DRA-65, DRA-70, and DRA-80
MMSSTV specific configuration for these DRA's

VOX Operation on the DRA-100
Understanding how to use the VOX on these DRA's

VOX Operation on the DRA-SR
Understanding how to use the VOX on these DRA's

Application and Windows® Support Information:

Disabling AGC and Signal Enhancement features in Windows®
Do this when you are having trouble setting the receive audio level.
For HP computer owners, also check out the article below.

Disabling AGC in a HP Laptop or Desktop
Do this when you are having trouble turning off AGC - because there's no "Custom" tab.

Disabling AGC and other audio enhancements in a Dell Laptop or Desktop
Do this when you are having trouble getting things to work and set correctly.

Winlink Express - an article by Scott Currie NS7C
For digital modes using USB sound-card interfaces like the DRA-Series. (2.75 MB PDF document)

Winlink Express - PowerPoint Presentation by Scott Currie NS7C
For digital modes using USB sound-card interfaces like the DRA-Series. (4.71 MB PPTX document)

Winlink Express - VARA-FM and VARA-HF PTT Support
The latest version of VARA (both VARA-FM and VARA-HF) now include built-in hardware PTT support.
Additional software is no longer required for hardware PTT with VARA HF, and the Winlink Express article above can be used generically to set up your DRA.

Winlink Express HF PTT - an article by Scott Currie NS7C
PTT support for ARDOP and Winmor with the RA and DRA Series. (394 kB PDF document)

FLDIGI's latest release includes C-Media GPIO PTT support for the DRA Series.
Scroll down to the section on C-Media GPIO PTT.

SoundModem PTT Support.
A help article originally written by Scott Currie NS7C.

Linux PTT issue when using DRAs under Linux as a "send only" device.
A solution to a problem under the Linux Operating System.

VARA FM Primer by George Thornton AE7G
VARA FM and Winlink set-up guide in html format.

Baofeng HT's and digital EMCOMM using VARA FM or FLDIGI by Barry Feierman K3EUI
VARA FM (narrow) or FLDIGI on the Baofeng portables.
Works with the Kenwood TH-D72 and TH-D74 too!

Radio Specific Information:

VHF & UHF Winlink Express on a budget using a Anytone AT-778UV by Dave Cavanaugh AG7DC
An informative article in PDF format - 1.51 MB local download.

The Yaesu FT-70D VARA FM portable station project by Hal Hazel WA7IB
An informative article in PDF format - 11.5MB local download.

A different twist on the FT-70D article above adding a way to listen to the channel without removing the radio plug.
A project by Hal Hazel - WA7IB
An informative article in PDF format - 14.05MB local download.

ICOM ID5100 connection to a DRA-39, DRA-39M, DRA-100-RJ45, or DRA-SR-RJ45.
This radio requires a two cable arrangement, and this article tells how to do it, and what's necessary.

TYT TH-9000 modification for connecting a modem or sound card.
This PDF article explains how to add a DB9 Female connector to a TYT TH-9000 radio for connecting other things - by Rick Muething KN6KB
An informative article in PDF format - 660kB local download.
Consider our AC-25 Accessory Connector for doing the modification.

Using an inexpensive Baofeng (or other HT) with the DRA Series sound cards.
This article is a follow-up to a QST article that shows how it's feasible to use a Baofeng HT with Winlink and VARA FM to transfer data over Amateur Radio.

DRA Product Menu
Ordering DRA products.

Products of Masters Communications, all rights reserved.
Specifications may change without notice.
Images are property of Kevin Custer W3KKC
Board layouts by Kevin Custer W3KKC
HTML 9/29/2020, Kevin Custer All Rights Reserved!