Mad Wax

The other thread isn't getting any replies, so thought this is a better place. Anyway I'm looking at a Futaba 3PK. There are two versions, the 40mhz FM and 40mhz PCM. I understand PCM is the better version? Can digital servos be used with both versions? (FP-R113ip and R203HF) or only the PCM version? What is HRS?

Is it safe to use a 9 cell battery pack? And what is a good charger? (not Futaba as I've found the wire insulation seems to be split) a charger with 6V output for RX would be useful also.

Tigger N. Bennie

HRS is accelerated FM and requires "all" digital servos. PCM is coded FM, but does not require digital servos. The manual for the Futaba T3PK is also available as a free Adobe download if you want to familiarize yourself with more of the HRS requirements and radios.

http://www.futaba-rc.com/manuals/index.html

Mad Wax

I bought the PCM version, is this the "better" one? I take it I can use digital or analogue servos with the PCM receiver?

Tigger N. Bennie

Yes, you can use either analog or digital servos with the PCM Module. Is it better? The signal is not as fast as HRS, but you don't need digital servos which could get very expensive if you were running a 1/5th scale with front and rear brakes. Myself, I have the PCM Module and the AM Conversion Module. The thing is I've seen numerous people end up using the Spektrum 2.4GHz module and receiver anyway. Although I purchased the Nomadio Sensor, I may trade away a JR XS3 set up with several receivers to one of the locals for the T3PK Spektrum set up. Enjoy the Futaba T3PK.

Mad Wax

I understood everthing you said until you said "Myself I have the AM conversion module"

Tigger N. Bennie

There are several modules for the Futaba T3PK:
1. PPM/HRS (uncoded FM/accelerated FM) / PCM (coded FM),
2. Synthesized,
3. Spektrum 2.4GHz, and the
4. AM Conversion Module.

The AM Conversion Module allows the Futaba T3PK to run "AM" R/Cs, such as the Kyosho Mini-Zs.

Mad Wax

You said the PCM version is slower, is that the delay time from the stick movement to actual servo movement? I take it the difference is in ms anyway?

Tigger N. Bennie

The manual that shipped with the Futaba T3PK used to assert that the transmitter in the HRS mode was 3x faster than any other transmitter--I haven't checked the online .pdf manual for specifics so it may have been changed since the website later had 2x faster than any transmitter. And though I also own the Nomadio Sensor, I haven't compared the specific stats but as far as I recall the rating was in ms. You should be able to read more by reviewing the manual at the link I provided earlier in this thread.

sandstormm

Im in Vegas too, however I got a pretty good deal If I want it on a 3pk but it has a HRS reciever. My question is can I use standard servos with this reciever? It says digitals are susposed to be used. Aslo can you run the HRS in a PCM mode?

Mad Wax

No have to run digital servos with the HRS version, and no HRS is FM only- not PCM. You'll need to change the module in the 3PK, new crystals for both, and the PCM receiver version. PCM apparently superior interference rejection. Both receivers have fail safe though. I bought the PCM version because of this (and flexibility with either digital or/and analogue servo compatibility)

I wish the bunded RX has more channels, I really could do with 1) Thottle 2) Brake 3) Left steering servo 4) Right steering servo 5) Front cable/hydro brake, plus a battery checker output tab. Mix L/R steering servo so with fine point on the TX (say one click on one to cut push/pull effect) saves you doing taking the RC plate off then horn, just to do a half turn...put back together, try again etc. A right pain.[]

Tigger N. Bennie

PCM is also FM--it's coded FM. See my earlier post. If you visit this link http://www.futaba-rc.com/radios/futj32.html and scroll down you should also notice that the stock number for the FM (PPM or uncoded FM) and the HRS receiver is "exactly" the same. The Futaba T3PK also has a brake mix and two other programmable mixes (in addition to the boat mix). The mixes and servos can also be adjusted via the screen without transmitting a signal.

Mad Wax

Yeah HRS and FM are the same TX & RX, but PCM system is not...which is what sandstorm was asking about.

You can't use analogue servos on the HRS/FM system- you must use digitals. Otherwise something will be damaged (servos and RX most likely)

You can use digital or analogue servos with the PCM version. You say HRS is faster, but considering my brother uses PCM radios for fast model planes I don't think it suffers from long lag times.

Tigger N. Bennie

Mad Wax,

The Futaba T3PK owner's manual asserts that HRS (accelerated FM) is faster, not me. I was very clear and specific when I mentioned that and provided the links above, so there is no reason to try and argue with me about which modulation is faster or not. It's my understand and belief that PPM (uncoded FM), PCM (coded FM), and HRS are types of different FM modulations, not different systems but someone else can search and provide links to the various modulations that exist. To me, this should be evident from the fact that PPM and HRS use the same Futaba module [and receiver], but only a different modulation selection on the transmitter itself. Yes, when using and selecting the HRS FM modulation "all" digital servos are required along with a few other things as I already mentioned in post #2 when I posted a response to your question and provided a link to the manual for suggested reading.

sandstormm,
If you are serious about purchasing a Futaba T3PK want to check out my Futaba T3PK hands on, PM me and perhaps we can meet at one of the local tracks. However, I don't plan to sell mine since I like it and have been using it for some time now unlike someone who has only recently purchased one or who is trying to sell you one.
________

As far as any further interpretation of the manual for the Futaba T3PK or the operation of the Futaba T3PK, I don't plan to post on this thread any further other than to suggest once again or reiterate that anyone who plans to purchase a Futaba T3PK, download the free Adobe manual and read it first. For those who already own the Futaba T3PK, I recommend that they read the manual. Again, the links are posted above.

Mad Wax

I'm not argueing with you, I'm just replying to sands question. Yes I know HRS is faster, but like I said if RC pilots use PCM then I doubt PCM is slow in the first place, therefore for a RC car that's moving 5 times slower bares little relevance that HRS is faster..so PCM is more than "fast enough" anyway.

zha50

As far as i understood it. . . .doesn't PPM, PCM and HRS all run off the same module and crystals.
Only thing that was different from the FM and PPM sets were the R113(PCM) and the R203HF receivers.

BTW i own a 3pk.

Tigger N. Bennie

Yes, actually the T3PK will transmit in PPM, PCM, and HRS--I should have written "module and receiver" earlier, not just module, and grouped 1 & 2 above. Thanks for catching that. The receiver is what makes the difference if one wants to receive in either PCM or HRS (besides the other HRS requirements). I also use the PPM mode for receivers such as the Novak XXL or when using the AM Conversion Module to run RTRs. Myself, I don't know which mode is used for the Synthesized Module or for the Spektrum RC Module. Is it PPM? Of course, there are actually more modules too if one splits up the available 27MHz and 75MHz modules.

Engrose

Or the 40 mhz modules

Tigger N. Bennie

Those too.

By the way, Spektrum RC FAQs.
http://www.spektrumrc.com/DSM/FAQs/Default.aspx

Harold348

Can I assume that the 3pk AM module can be used with any 3pk? I have the first generation gold 3pk and recently bought a Mini Z. Purchased the AM 27mhz module from Tower and took the crystal from the standard Mini Z controller and put it in the module but for some reason there is no response between the transmitter and the Mini Z. Any comments appreciated.

phalaecus

Harold348,
I suppose your problem is due to the fact that Ko Propo crystals do not work with Futaba transmitter. By any way, please let me know if and how you solved the problem, as I wish buy the AM 27mhz module for my Mini-Z, too.

Ciao