The RVS-8 audio Voter, by LDG Electronics, Maryland


Voter

Introduction

A "voter" is a device used in a LMR base station, or better yet, a repeated station. Several remote (input) receivers at various remote locations pick up a user's weak signal, and then are transported them back to a Master Control Point (MCP) by means of dedicated RF, wireline or IP channels for each of those remote receivers. At the MCP the voter "decides" which of the "best" user signal will be heard by the control station, or better yet, sent back out to the remoted (supported) system output transmitter for all to enjoy the best reception possible. This can provide superior reception and user coverage over a conventional single-Tx/Rx repeater station at one remote site. This comes with a price, starting with cost (equipment, sites, etc.) advanced experience, understanding and very high maintenance discipline and standards by the supporting technicians. Voters come in two basic types; time domain or signal-to-noise quality (S/N). The latter is more popular and effective for best LMR communications,

Voters in General

Two manufactures are known to produce a S/N voter for Amateur Radio repeaters. Doug Hall makes a 4-channel, while LDG Electronics makes an 8-channel. Both are the S/N type and neither require a status tone, like the Motorola and GE comparator shelves (voters) do. By not needing a status tone the remote links don't have to be active (keyed-up) before or after the user activity. For this article we will discuss the LDG voter, model RVS-8.

One other note as of June 2013, it was learned of the possibility the DHE voter will no longer be made. That's a tragedy however, the Author understands the economics of that decision.

The RVS-8 Voter

The model probably went through some changes and versions since it was introduced over a decade ago. A comparison chart is started, here, but not completed due to time for research. Two rows of "fields" are left blank, possibly, to be filled in at a later time.


 
Vintage-Versions Manual Board Schematic Firmware & 2
Original 
Before 2001 
2001 2.1 2.1 2.0 2.1
2005-2007  1.0  3.4  3.2 ?
2008-  who knows?  who knows?  who knows? who knows?



History and Service

The author ordered the RVS-8 on August 21st, 2005, through the U.S. mail and received the unit Sept 10th, in great physical condition. They pack the unit well and attempted good communications. If you're a slow, western-er "county hick" like the Author, you'll need to get up to "speed" on the East coast's way of talking and doing things. They operate at a much fast pace however, do provide a quality product. This unit was slated for the 147.20 repeater, however was returned shortly afterward. This was due to a few reasons that's beyond the scope of this documentation. The short reason is it did not work. A later version was obtained on April 12, 2007.

The unit's fairly simple in design and construction. Being that this is the first micro-processor based piece of equipment on the SRG system, this is out of the "comfort zone" for the Author. The Author's been studying the documentation on their web site which, the manual is down loadable with no obligation. That's a real nice touch. If other companies for repeater equipment could offer that, we (honest) Amateurs could study what we are interested, so we don't waste a lot of time and frustration and end up shipping something back, to our expense. By seeing what the product does makes easier selection to your needs. More on the documentation at the bottom of this page.

Here's some pictures of the unit, which is an earlier version, should you be considering buying one for your repeater. For larger version of the picture(s) just click on the images. If you do that, it's better if you have a high-speed connection, since some of them are rather large.

The unit........

 

 

 




The front panel........

 

 

 




The rear connection points.......

 

 

 







Here's the main board. On the right is an area the author was working with on the COR inputs.


 

 

 

 

 

 

 










Here's a sectional of the board in third's, for a closer view of each section. Reminder: for a larger version click on the image(s).