[VHFcontesting] ROVER Power Needs And Solutions during a VHF Contest.

[nosigma at aol.com]

Tim,
Your experience with the Russian Radar remind me of working on a Russian Rebege radar and mobile missile launcher in 94.  My buddy was down in the launch tube with an access door open to a high power supply.  He dropped a LARGE diameter screw driver and I swear plasma shot out of the launch tube. He was OK (hair was burned off, stank bad) but it melted the 1/2 diameter shaft screwdriver in half in a flash. The generator surged something awful but the radar was fine.......


To the OP.
Getting back on topic.  I drive to mountain tops and operate as a fixed station running off batteries and the alternator.  I manually connect a hot lead from the engine battery to the station batteries that are cab mounted to charge them up.  I also carry a spare engine battery just in case I forget to disconnect and drain everything down. I also carry a spare alternator.


I run a pretty cheap set up.  Two group 24 deep cycle marine batteries in parallel and a TGE batter booster to keep everything at 13.5 volts.  I pull about 35 amps on TX with the radio, amps, computer and cell phone on charge.  Lighting is by battery powered LEDs or a head lamp.  I run my batteries down from 12.4 to 11.3 volts in about 30 to 45 minutes depending on how busy I am.  FM is not busy but you call CQ constantly praying for an answer.  The batteries  hold at 11.8 for quite a while.  


I lost a cell in one of these batteries late Sunday afternoon last September and it started pumping hydrogen sulfide gas into the vehicle.  I was able to take it for several hour since I had the doors off and hatch open.  I was  never so happy to make the final sched with K8GP/R so I could bail out with a sore throat and burning lungs.  Having two batteries and the TGE booster (plus a little stupidity) is all that kept me on the air.  If this had happened last January it would have been a disasterous event for my contest score (doors closed to stay warm so I would have to have shut down).


Now after 4 contests on that set up I am seeing the batteries start to drain down faster and take longer to charge back up.  They may need replaced soon.  They are cheap but when you have to replace 3 of them in 2 years with something better (6V golf cart batteries are ideal) it is more expensive in the long run.


I am looking at two options right now:
I pulled the AC off my rig years ago and I could easily put a dedicated alternator in the compressors place. Isolation as described in earlier posts.


I may also go to an inverter generator and a 50A power supply.  Its a lot of extra stuff to drag along.  Every field day I hear them sputter to a stop because everyone forgets to fuel them, another thing to worry about.


Lots of great advice below.  My set up works but it has risks and is far from optimal.


73
John
KM4KMU