o.s 21vspec

could somone please shed some light on what or if there are any advantages on using digital servos,do they hold there posistion better under pressure?
i am currently using a hitec 945 for my steering in my 1/8 buggy,with a futabs 3pk with pcm reciever.
can you use digital servoes with this reciever,as i am thinking about getting the sanwa erg-vx servo for my steering.

rockdragon

Digital servos are OK to use with standard PCM receivers but not the stanadrd servos with the digital HRS receiver as permanant damage will be occured to the standard servos (smoke). If you want to use the HRS receiver, then you must ONLY use with the digital servos. Here is[link=http://www.futaba-rc.com/servos/digitalservos.pdf] info of the digital servo from Futaba[/link].

Tigger N. Bennie

Dumb question then rockdragon, why can't you simply use analog servos and set the Fubtaba T3PK to the PPM (standard FM) mode instead of the HRS mode? After all, the receiver has the same stock number for both the FM and HRS modulation--only the PCM module lists a different receiver. http://www.futaba-rc.com/radios/futj32.html

Tigger N. Bennie

I also own a Futaba T3PK, a PCM Receiver Module (coded FM), and use digital servos as well as Novak receivers with the Futaba T3PK. For your information, the manual is also is downloadable at Futaba's website if you don't have one and the AM Conversion Module works well. I have yet to try the synthesized module or the Spektrum module in the Futaba T3PK and probably won't since I purchased a Nomadio Sensor.

rockdragon

The R203HF HRS Rx and the R113iP PCM1024 Rx are not the same and you need to select the modulation mode on the Tx in order to gain the best out of each one.
When using T3PK with the R203HF HRS Rx, the selection is HRS.
When using T3PK with the R113iP PCM1024 Rx, the selection is PCM.
The PPM mode is for FM Rx such as R133F Rx and the Spektrum.
If not correct setting was made, the Rx will not respone to the signal from the Tx.
The detail of how to set the modulation mode is on page 16 of the 3PK instruction manual.

ATTENTION: on page 7 of the 3PK instruction manual mentions about the servo with HRS Rx.
Quote: "NEVER use non-digital servos with HRS receivers. Severe damage to all electronics may result, including the possibility of a fire. Only digital servos may be used with HRS receivers, including for throttle."

Tigger N. Bennie

I know the R113iP is different and does not function in uncoded FM or HRS. I also know based on the instructions that you are not supposed to run analog servos in the HRS mode; however, the Futaba website also shows that the R203HF Rx is not just for HRS, but for FM (uncoded) as well. If this is not the case, then what is the stock and model number of this "other" receiver module? By the way, the PPM or uncoded FM mode is also for using the AM Conversion Module.

rockdragon

Do you mean [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXAKM3&P=M]the R133F Rx [/link] ?
[link=http://www.futaba-rc.com/radioaccys/futl26.html]Manufacturer Stock# FUTL0305 : R133F 3-Ch FM Rx 27MHz w/o Short Crystal
Manufacturer Stock# FUTL0309 : R133F 3-Ch FM Rx 75MHz w/o Short Crystal[/link]
.

Tigger N. Bennie

What I mean is what "other" receiver unit ships with the Futaba T3PK that simply runs in uncoded FM if it is not the R203HF as shown on Futaba's website? I already know it is not the R113iP (PCM or coded FM) and according to you it is not the same receiver as the R203HF.

Perhaps, someone can tell me if they have tried using the R203HF in the PPM mode with analog servos?

I have already found this information regarding the synthesized module posted on another thread. However, to me it is unclear unless the specific R203HF requires that the transmitter be set to the HRS mode whereby something like the synthesized module can use all three and the PCM module use two of the three modes. If so, the R203HF must really limit the transmitter.

http://www.rcuniverse.com/forum/m_28...tm.htm#2831190

Graystar

To answer the original question...

Yes, digital servos are better than analog because they have a much quicker reaction time. This allows them to hold their position better and to react faster to signal inputs.

An analog servo feeds off of the input signal. That signal acts as the director for all action in the servo. A digital servo, however, has a computer that directs the servo activity. The signal is simply an input into the computer. The computer then decides what to do. So the computer will send adjustments to the servo motor at a greater rate than the analog signal. This lets the servo hold it's position better.

o.s 21vspec

can somone tell me if the sanwa erg-vx is a digital servo or analog?

Blokie

Could anyone answer the above question please??

I have just bought the HRS version of the Spektrum module/receiver for my Futaba 3PK, and I'm having issues with my servos (interference type behaviour) which I have never had with my 113ip PPM module/receiver set....

My servo's are Sanwa (Airtronics) ERG-VX on the steering and ERG-RZ on the throttle.

Are these servo's digital and compatible with a 3PK in HRS mode?? I thought they were, but now I'm not so sure!!

If I can confirm the above then I can start looking into whether it is a problem with my transmitter or the newly purchased Spektrum kit :-(

Cheers,

Mark
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HaveBlue

I dont know if this is a similar problem , but I bought the specktrum pro module for my 3PK, and was surprised to find that the servos glitched at very short range ..about a foot or so away.. now I didnt get the HRS version , just the the PPM, ..I ended up sending an email to Horizon Hobbies as I was expecting a totally glitch free system..they advised me that the Tx and Rx can fight against each other at short range two feet or less...but apart from this issue the system works fantastic

just for reference I am using analogue servos two S9402 for brake/throttle duty and a NES605 for steering..probably going to update to digitals soon ..probably 5050 /9350

mkincy

the Sanwa (Airtronics) ERG-series is not digital. and to my knowledge all of the AT high-end servo's are analog.

Blokie

Thanks Guys.

I am going to sell the servos as I have just purchased a pair of Futaba digital S9351s which are working perfectly with the Spektrum HRS kit.

Mark
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