[VHFcontesting] Batteries

[Rick R]

As a rover for 25 years, I have had much experience with batteries and rigs. Here are some experiences and thoughts:

Many rovers running multiple big batteries (generally deep cycle marine type) also use the TGE voltage boosters (see Tim's QST ad) or the Jacobs Accuvolt. That way, you can set the voltage (say ~13.5V) to be delivered to the rigs, even if the battery runs down to 10-11 volts. Yes, the batteries then need a recharge and the vehicle's alternator needs to be capable of recharging the batteries between rover location stops. A fully charged marine battery that has a 100Ahr rating can usually run a 100W output rig for about 3 hrs, depending on how much of the time you are transmitting, based on my experience. Remember that that 100w output requires about 25 amps of power, 20 for the amp, and likely 5A for associated electronics like the computer, lights, rotor, possible inverter, etc. My 375W TE 2m amp draws 53A on xmt.

Some rigs will not operate well once the voltage starts dropping to 12V or below. Most were designed to operate at 13.8V optimally. I have had that problem with my trusty old FT736R. I get bad audio reports when the voltage sags. Sometimes the digital freq display goes down, and that's the signal that the voltage is too low. I see others have had that experience, and the rig internal computer wants to reset itself.

How have I managed over the years? I run the engine almost continuously when I rove, using the alternator to boost and recharge the batteries continuously. I use 6 marine batteries, all rated at 100Ah. Two sets are in parallel and 1 set in series for two of my uW amps that run off 24VDC. I have a 100A solenoid to switch the automobile power to the batteries and I have a 50A fuse in the line, and I monitor the charging with a 50A ammeter and a 0-20V voltmeter. I only charge the 12V parallel banks, not the 24V series set as those batteries generally last an entire weekend, as the amps they run are for 903 and 2304, and although the amps on those bands are about 100W each, they are used for far less transmitting on the weekend than does my 375W TE 2m amp. I have an E-150 1994 Ford van for roving and there is very little electrical hash when it is running. I also have a Honda 2KW generator, but never used it on the road as I had the above the scheme. My rover ran 160w on 6, 300+w on 2, 120w on 222, 100w on 432, 100w on 903, 120w on 1296, 80w on 2.3, 40w on 3.4 and a few watts each on 5, 10 and 24G.  Rick, K1DS