Range Testing Stories
Pump problem
One year, at the Florida Jets, Bob Violett had his brand-new (2nd flight) Bandit go into hold on landing. Fortunately, he got it down okay, despite intermittent control. He asked me to check it out. The engine-off test showed that he had about 50 paces of range- not bad. Engine on, he had only about 15. The culprit? I noticed the antenna was in close proximity to the turbine's fuel pump (about an inch away.) By re-routing the antenna to the other side of the fuse, we tripled his ground range- and he has put over 200 successful flights on the Bandit. My guess is that while his test flight in private was fine, when landing with plenty of transmitters close by, the radio went "over the waterfall".
Lucky save
A fellow giant scale flyer, with a spark ignition system, was noticing that his model was occasionally "not locked in". We did a range test with his 8103, antenna off and he had 121 feet- not too bad for conditions. With the engine running, he got only 38- one-third his regular range. Looking at his installation, he had a number of Giant Scale "no-no's"... his throttle servo was located in close proximity to his ignition system, plus his throttle pushrod was metal - both great ways to play havoc with your radio. Even though he'd had several successful flights, he wisely quit flying for the day. A re-routing of equipment brought his engine-on range to within 10% of engine off.
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Poor range had nothing to do with range at all
A modeller getting ready to fly his nice new giant scale Bearcat came over to me and said he was having troubles. Seems he couldn't get but a few feet away from his model and control would become "crazy". Indeed, even though he had a PCM 649 receiver, he would get control interaction - his flaps would go down at odd times - none of the controls were "solid". I asked if we could get to his receiver, and he popped off a bottom hatch. When I plugged a freshly charged battery into his receiver, the system snapped to and worked perfectly. The culprit? He used another brand of switch harness whose lightweight leads deprived the receiver of its correct voltage. The moral: Stick to quality JR components. They cost more, but they work.
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