Hey guys may be a stupid question but what's the difference between the futaba ground receiver's.

With FASST there are 2 protocols, not compatible with each other

With FHSS there is:

S-FHSS, no telemetry and low framerate
T-FHSS, supports telemetry, high speed framerate
T-FHSS-SR, supports telemetry, high speed framerates and SR mode (super high speed servo's)

Don't forget there's also just FHSS, in addition to the S and T variants.

Futaba has a good chart to determine what receiver is compatible with what transmitter. https://futabausa.com/receiver-feature-charts/

If you asking a more general question...the main differences are number of channels, but some don't have external antennas which are nice because you don't need to worry about routing an antenna somewhere.

New futaba question. anyone have a bad Futab a RX cause their transponder to skip laps??
the owner of my LHS says he has seen this many times. I just had it happen to me R204gf-E in my B5m stock buggy.

put in a different RX and the probloem went away.

Within the receiver the power on all channels are parallel connected so basically no way the receiver electronics is causing it. But a dirty contact or a bad soldered pin header could be the cause of your issue

I have seen many 203/204 gfe series of receivers doing many odd things including missing laps and cars taking off etc.I believe that there has been some bad runs produced on these receivers for sure

Drbrake seen this happen many times..with many different rx makers..a cold solder joint will cause this to happen..

its all response speed. The fastest response would be the t-fhss SR receivers. but SR mode need to be turned on the radio and it requires a SR compatible servo and the servo need to be pugged in to the radio and sr mode also need to be turned on for the servo. When sr mode is turn on this is the fastest response speed but there is no telemetry. Only the futaba 7px and 4pm are compatible with T-FHSS-SR. Receivers are the r334sbs and r334sbs-e. The E receivers have an internal antenna and are only suppose to be used only with electric cars Where as the non E receivers can be used for both electric and nitro/gas cars. With SR mode turned off or when its being used with a servo without SR capabilities the receiver will function as a t-fhss receiver. the r334sbs and r334sbs-e can also be used on a radio that is not SR compatible like the futaba 4px and 4pv but the receivers will function as a t-fhss receive.

T-fhss is slower but has telemetry.

fasst is old and even slower

s-fhss is even slower

fhss is slowest

top end radio like the 7px is compatible with all the above type of signals and receivers. Some lower end radios are only compatible with certain signals/receivers.

Do I understand you that the T-FHSS-SR can do BOTH SR and Telemetry at same time? I thought it was one or the other.. ?
if you wanted to run optimally, what mode would you select assuming the latest 7PXR and latest HPS-CB700 servo? with GPS, Gyro's and other telemetry thrown in...

this is my exact setup. I run the 7px with the ct700 servo in most of my cars.

and no there is no telemetry with sr mode. If you want telemetry you would have to run in the slower
t-FHASS mode

the ultimately in transmitter signal speed and performance would be a 7px with a r334sbs/r334sbs reciever with a futaba ct700/cb700 servo. You first need to plug the servo into the 7px and turn the sr mode on the ct700 servo to the fastest sr mode type 3. Then when you bind the reciever to the 7px make sure you bind with signal t-fhass SR and not t-fhass. Then you go to channel 2 on the 7px for the steering servo and turn sr mode ON. Down. Now you have the fastest transmitter speed and highest power servo setup on the market.

Remember when servo is set to sr mode it will not work with any other transmitter system that is not setup to run futaba sr servos. The servo must be plugged in to the 7px and sr mode must be turned off in order for the servo to function in other non futaba sr transmitters.

also older and cheeper futaba servos that are capable of sr mode like the Bls571sv or the s9373sv or the s9372sv can only be run in the slower sr type 1 mode and not in sr type 3

True, in SR there is no telemetry, not sure if only a receiver voltage is shown. I do not use that stuff

with sr mode there is no telemetry so not even receiver voltage is shown. To show receiver voltage you must bind the r334sbs receiver with t-FHAss mode and not t-fhassSr mode and turn on the telemetry in t-fhass mode.

so in all honestly, for a new driver who's more interested in the tech of these cars and the modification aspect, than extreme driving and bashing ... what mode would you use? What exactly does SR give you that normal modes don't?

SR is a Super Response mode only working with SR compatible servo's.
So you need to use the T-FHSS mode to use telemetry, still the T-FHSS mode is ewsonable high speed with arround 300Hz framerate.

with sr mode on the transmitter and with sr mode turn on with A sr compatible servo over normal t-FHASS mode you will get the ultimate in transmitter signal speed. Meaning when you turn the steering wheel on your transmitter the car with get the signal faster and the actual wheels on the car will turn earlier because the signal is received faster.

realistically this is hard to notice with novice drivers. This is most noticeable for fast racing with a lot of fast steering inputs like 1/12 scale mod carpet racing. Must less noticeable almost impossible to notice for off road racing or for bashing.