I have completed the install to a comp-arf flash. I have used two 2100mah lipo's, a powerbox sensor,Rx is a JR10DS witha graupner whip aerial, mounted like many people have halfway down the fuz, and I use a JR PCM9 as a TX. I am getting 40yds range with the fully charged lipo's but 48yds range with a single 4.8v NIMH that I half tried it with. I also notice that the range drops off to only 25yds if the lipo's get partly discharged. Is this acceptable and why is the NIMH producing a better range. I would add the ranges are the same for engine off or on but if I take the RX out of the model ( with whip aeria)l and test it with a single servo and the NIMH battery then the range is 80yds.

John

John

Something strange there as the Sensor switch regulates to 5.9v and the Li-Po does not get that low!
The voltage drop I see in 7-8 flights makes no difference to my range.
Are your servos musical? if you put the flaps to mid position does it change the range, if you disconnect each of the four wing servos one by one does it increase?

Only thing I can think of is more servo noise at the higher voltage using the sensor switch.

There are now at least 12 Flashes flying with my/your set up in the UK.

Dave

Definately unacceptable range John, I'm using a similar setup with JR servos, sensor switch, etc. in my Rookie and to be honest I have not found the ground range limit, get fed up of walking once I reach the edge of the flying field.

Good advise from Dave hope you get it sorted.

Rob.

John,
Something is very screwy.. Do a baseline range check with your receiver battery and one servo... that's it lay that stuff on a table about 3 feet above the ground. What range do you get with this setup? Extend you antenna on the 9C transmitter to a length of 7 inches. You should get at least 300 paces / 600 feet.

Then re-install the receiver in your flash... and do another (installed baseline) check (turbine ECU unplugged). What if any is the range difference, between a raw baseline, and installed baseline? There shouldn't be any difference between the Raw baseline, and the installed baseline. Obviously if there is a difference some other component i.e. batt, wiring, servos, something is wrong. Correct that problem first.

Then do a full power turbine running range check you shouldn't lose more that 20% maximum range between the installed baseline and the powered up range check. 20% of 600 is 120 feet so with full power turbine running you should be able to get at least 580 feet range.

For starters if you can't get around 600 feet range with a Raw range check get the transmitter / receiver aligned / tuned. Then go from there step-by-step.

Or you could just get a DX-7 and be done with range problems altogether)
Lee H. DeMary
AMA 36099

Thanks for the advice. I,m doing the range check with my TX aerial down (JR) is this correct?

John

I'm not sure about the PCM9, but the 10x you do it with the antenna removed.

kc

John,
No do it the way I told you antenna attached and adjusted to 7 inches. This will enable you to compare your distances to any other radio brand made. I own a 10X, 14MZ, and older JR 7 channel PCM's. It does matter what kind of radio you use when you set the transmitter antenna to a standard length.

If you want to do the range check with the antenna removed the baseline distance should be 300 feet, but the transmitter module might get a little hot.

Completely ignore what JR says... they are trying to sell everything they have no matter how bad it is. The 50 foot they suggest isn't good enough to put in a kite! Remember they don't want you to know the difference between junk and normal.
Lee H. DeMary
AMA 36099

it can get that low if one of his servo,s or more are strugling..
if i am not mistaking the regulator can only take a few amps (5?)
if you program the flaps wrong from the flash it can take a lot of power from the regulator and create lots of noice.
to be honnest i use the Emcotec BIC for this.
it shows you real time the current amps the system is using and therefor exelent to search for problems like this.
as for battery,s
i always flew my flash with 2 x 1800 mah lipo,s.

is it possible you drilled your antenna hole where there is a carbon strip in the fuselage?
if so thatis like connecting a large metal strip to your antenna..

you told me you had only a 30ft landing strip needed for your flying skills..