[ARC5] SCR274 field test

[J Mcvey via ARC5]

I was hoping that I could run the dual rx/tx setup off of my  jeep battery, but it seems it needs a stiffer deep cycle type to keep up with the load in transmit. The jeep batter sagged badly and for that matter so did the deep cycle battery (11v under full load), but it was sufficient to keep things working. 
I think i'm missing something about the nature of dynamotors and batteries ...
With the two transmitter filaments ( 4X 1625) @ 2a and the rx pulling about 2.5a, that's a constant 4.5a, add the dyno in stanby which bring the the total cw break-in receive mode 7.5a. 
The dyno says 9a @ 12V continuous duty for 440v @ 200 ma .That should be a max of 16.5a a key down. So how can 16.5 amps draw a 130AH battery down to 11v from it's fully charged resting voltage of 12.6v ? ( it recovers on key up)
When I was using a SMPS, it sounded good, now I've got some chirp due to power droop.What say you experts?
BTW, I was doing this in "original spec" using a very short wire antenna of about 35 feet on 80 meters in NVIS config. Loads right up at about 50% inductance with coupling also about 50%. I like to stick a NE-2 ( leads shorted together) in the antenna clip on the bc-442 to see how bright I can make it glow. It tracks well with antenna current.