The Repeater Radio Assembly or RRA is housed by a Pelican 1610 rolling air tight case complete with radio, power supply, 4 AGM 7.5amp batteries, 2 intake fans, 1 exhaust fan and like the ERA, plenty of flair to impress your friends and family.

Though this model could easily be used for only simplex operation in an emergency it was designed specifically to house a NHRC 3+ repeater controller and two Yaesu FT-7800R dual band mobile radios. Unlike the ERA the RRA is missing the 400 watt DC/AC inverter in order to provide space for the repeater system.

There are several improvements in the RRA over the ERA and in fact I might modify the ERA to match. One major fundamental flaw with the ERA was the fact that all four corners of the diamond plate console were screwed into rails mounted on the main body. While this gives it the military mounted looked, it does not allow for easy manipulation of either the radios or the power system of the assembly. As a result, the RRA is designed with two hinges and no screws to prevent the lid from easily being opened.

Along with the hinge improvements I also ditched the idea of using the West Mountain RIG Runner for the primary power distribution on the back side of the console. The RIG Runner that was wiring the batteries in parallel was also replaced, in favor of a Blue Sea Systems dual bus terminal. For power distribution I again used a Blue Sea Systems blade fuse power distribution terminal which included a built in ground bus. While Powerpoles are convenient and secure for connecting individual components they are not clean enough to distribute power to switches from separate ground and 12v sources. The wire routing when using Powerpoles becomes a serious issue and from now on I’ll only be using them out to the actual components like the radios.

I chose to use a Cobalt Amplifier Ammeter instead of using the analog or digital shunt meter that the ERA uses. There are two major drawbacks to this, the first being that this particular gauge only displays increments of whole amps, the second is its price at around $180, less on Ebay. The Cobalt gauge was far easier to install than the shunted digital meter on the ERA and as was pointed out to me recently I could wrap the 12V cable around it’s transducer ten times to increase my precision. I might try this however I’m not sure I can get the 12ga wire wrapped around the transducer 10 times due to space constraints, we shall see.

Because there will be two radios in this assembly the two 1/4 “ jacks are each tied to an individual radio. The toggle switch in this model is a DPDT which will set the speaker on one radio, the other or off. If both radios are required to be in use where the repeater would be shut off and they are in an individual capacity a second speaker would need to be plugged in to one of the 1/4 “ jacks.

The repeater itself will be set up for three separate situations, simplex repeat, normal repeater and emergency repeater (IDing as the ARES/RACES repeater). This should allow for use in just about any operation whether it be showing off to other HAMs or an actual emergency.

The circuitry of the RRA for the most part is wired identically to the ERA, hower, since this was a second revision it is much cleaner and more efficient. If you have any question be sure to contact me in our Google Groups or feel free to leave a comment on this post, we’d love to hear your opinions!

Below is a partial parts list, it includes parts from both the ERA and the RRA:

Equipment	Part Number	Website
NHRC-3+		NHRC
Yaesu FT-7800R		Ham Radio Outlet
AGM Batteries 12V 7.5AMP		Powerwerx
West Moutain PWR Gate		Powerwerx
West Mountain RIG Runner		Powerwerx
Digital 12V Voltmeter Gauge	SUM-G2983	Summit Racing
Red LED 80mm Antec Fans	55011242	Radio Shack
ON/OFF Toggle Switch	2750602	Radio Shack
120V Fuse Holder	2700367	Radio Shack
120V Square Lamp	2720704	Radio Shack
ON/OFF/ON DPDT Labeled Switch	2751533	Radio Shack
80mm Fan Gauges	55010839	Radio Shack
Blue Sea Systems Bettery Switch	2880	Sailnet
CB/HAM Speaker	19-318	Radio Shack
Diamond Plate Sheet		Orchard Supply Hardware
50' 12GA RED/BLACK Zipcord		Powerwerx
Blue Sea Systems Blade Fuse Block	5031	Blue Sea Systems