catspaw

I'm finally thinking of switching to 2.4, and am starting to research the various radios out there.

One online review of the the Futaba 7C FASST claimed it requires digital servos.

Is this true? does 2.4Ghz REQUIRE digital? I'd rather not have to purchase a bunch of servos on top the the radio and RX's.
I need to clarify this.
Thanks!

exeter_acres

My Feedback: (2)

link to review??


not true....

can run any servo you want...

jaka

Hi!
Of course it's not true!
Have been using my 34 year old Futaba S6 servos with my DX-7 and many, many other analog servos too.

catspaw

OK, good to know.

As for the review, now I can't find it. I thought it was one of the ones provided by RCU or RCgroups, but they aren't it, and I can't remember offhand where I read some other reviews.

OK, now has anyone done a comparision chart between the Futaba 7C and the Spectrum DX7? (I know, a bit OT for this subject line)

TedMo

I have not done comparison but can say this no comparison is necessary you can't go wrong with DX7.

ww2birds

My Feedback: (14)

I have not seen any of the manufacturers of 2.4 equipment say this. I have a bunch of Futaba FASST and a DX-7 with a mix of analog and digital servos. Everything works fine.

The only point that is close to this statement relates to the new(est) FASST HS (High Speed) receivers, which can have channels 1-7 set to "normal" speed where they can use any servos, or high-speed mode (7 ms update rate) where, for channels 1-7, digital servos must be used, since they can accept the faster frame rate.

You have the choice of how to setup the 6014HS and 608HS, my 6014 HS came set to non-HS mode, which can use any servo, you have to change it to HS mode if you want to use it.

Seems pretty intelligent to me ... and perhaps if misunderstood or misquoted, could have been seen as "must use digitals with 2.4". The actual statement would be if you want the 7 ms update rate (fastest available, as far as I know), you have to use digitals on the seven high-speed channels.

FWIW, being the curious type, I did plug an analog servo (one I could accept being fried...) into one of the 6014 HS channels while set to HS mode, and it did work but buzzed and jittered quite a bit .. clearly not something you'd ever do with an airplane, but amusing on the bench.

Its actually kind of neat to see how fast the servos track in this mode, if you flick the stick on the TX the servo follows the oscillation of the stick as it recovers. We'll have to see if its noticable in actual flight conditions...

Dave McQ

fiery

My Feedback: (2)

The Airtronics SD-10G in FHSS3 transmission mode will not work with some analog servo's due to the high frame rate. This is from HobbyPeoples web site entry .

Read up on the radio if you want more details.

freeair

actually alot of the DX7 radios came with Digital servos [ ds-821 ] i run both digitals and anologe servos with my JR 2.4 gig and can tell you guys that the digitals may be better in terms of speed and centering but when it comes down to low battery power, the digitals will stop before the anologe does. i found this out when bench testing a new model that was fitted with 5 digi servos and 2 anologe servos, receiver battery power was down and all of a sudden the digital servos would no longer move compared to the 2 anologes that did still move but abit slower than normal. so if i was flying a model and receiver battery power went down to low, i know the anologes would get me back to earth. if you guys have this mix of servos , try doing this low voltage rx test and see which servo stops functioning first.

ww2birds

My Feedback: (14)

Freeair's observation holds true for Futaba gear. I was doing a low-voltage operational test on the 6014 HS Rx and found that the JR and Futaba digital servos I had on hand stopped working about 0.1 or 0.2 volts higher than the RX, so there is a small voltage range where the digital servos do not function but the Rx does.

The only caveat here is that the voltage range is so low, and as I recall under 3V, that the battery discharge curve is very steep for most battery types, so the time difference associated with this voltage difference is not much .. maybe seconds or tens of seconds.

Dave

DougV

I have both the DX7 and the FASST 7C, and with both radios I use analog or digitals.

Doug.

Silent-AV8R

The Futaba 6014HS, 6008HS and the new 6-channel High Speed RX require the use of digital servos when the RX is set to High Speed mode. Otherwise you can use either analog or digital when in normal mode. The HS mode is a feature really only useful in extreme helicopter 3D flying. It has a faster frame rate to allow the digital servos to achieve full holding torque faster. It does not make the servos faster, increase resolution or reduce latency.

bruce88123

Let's get this right. The R6008HS & R6014HS only require Digitals for the first 6 channels in the high speed mode. http://manuals.hobbico.com/fut/r6008...4hs-manual.pdf

Silent-AV8R

That is correct.

In normal mode you can use either/or analog and digital servos as you see fit on any of the 8 or 14 channels.

In High speed mode you MUST use digital servos on channels 1 through 6. Channels 7 through 8 or 14 can use either digital or analog regardless of the mode the receiver is set to.

High Speed mode on these receivers is really only going to show a benefit when flying extremely aggressive 3D aerobatics with a heli. You will be hard pressed to notice a difference with any airplane.

ww2birds

My Feedback: (14)

Thanks for the correction. re: 1-6 vs. 1-7 I am away from my jet hardware at the moment so did it by memory .. which really does go down hill after 50!

Dave