Choosing gear for FPV radios & batteries starts with a role decision: are you adding an ExpressLRS receiver to a model, or buying a transmitter to control it? A lower price does not help if the hardware type or channel requirement is wrong. The receiver choices differ in channel count and signal-focused features, while the controller choice has a different condition. Start with the job, then use the prices to compare the tradeoffs.
Quick take
- For a model-side receiver, compare the RadioMaster ER4, ER8, and RP3 V2 rather than the transmitter.
- For pilot-side control, the Jumper T20 is the relevant choice, but its used condition and stated gimbal issue need to be part of the decision.
- The full listed-price spread is $57.50, so the receiver-versus-transmitter distinction matters more than treating all four choices as substitutes.
Listed-price comparison
The prices cover three receiver formats and one handheld controller, with the bars showing their relative positions across this group.
| Product | Listed price | Price bar | Role |
|---|---|---|---|
| RadioMaster ER4 ExpressLRS (ELRS) 2.4GHz 4-Channel Receiver [RM-HP0157.RX-ER4 | USD 17.49 | 4-channel receiver | |
| RadioMaster ER8 ExpressLRS (ELRS) 2.4GHz 8 Channel Receiver [RM-HP0157.RX-ER8 | USD 40.99 | 8-channel receiver | |
| RadioMaster RP3 V2 ExpressLRS (ELRS) 2.4Ghz Receiver [RM-HP0157.RX-RP3-V2 | USD 22.49 | 2.4GHz receiver | |
| Jumper T20 Radio Controller Transmitter ELRS for RC FPV 2.4GHz(READ DESCRIPTION | USD 74.99 | ELRS transmitter |
Decision matrix
- Hardware role: ER4, ER8, and RP3 V2 are receivers for the model. T20 is a transmitter for the pilot.
- Connection planning: ER4 and ER8 represent four- and eight-channel layouts. ER8 is framed for fixed-wing use and support for eight servos, while ER4 supports four simultaneous PWM channels.
- Signal-oriented features: RP3 V2 brings antenna diversity, a built-in TCXO, an LNA, a PA, two antennas, and Wi-Fi updates into the comparison.
- Condition and repair: ER4, ER8, and RP3 V2 are marked new. T20 is used, with a right-gimbal cleaning or replacement issue and a reported roll-axis delay.
Product notes
RadioMaster ER4 ExpressLRS (ELRS) 2.4GHz 4-Channel Receiver [RM-HP0157.RX-ER4
At $17.49, ER4 uses ExpressLRS at 2.4GHz with four simultaneous PWM channels. Its compact design and stated fit for small aircraft, boats, cars, and other models make it a clear match when the model needs a lightweight receiver rather than a handheld radio. The limitation is its four-channel capacity: a setup needing more servo channels points to a different receiver. ER4 also includes high-speed response and ultra-long-range capability, but it remains receiver hardware, not a pilot-side controller. Choose it for a compact model with a four-channel requirement; leave it out when the job is controlling the model from the pilot's hands.
RadioMaster ER8 ExpressLRS (ELRS) 2.4GHz 8 Channel Receiver [RM-HP0157.RX-ER8
ER8 costs $40.99 and is designed for fixed-wing users, with support for eight servos and eight channels. That makes it a practical match when the airframe's control layout calls for more connections than a four-channel receiver offers. Its power-supply range is DC 4.5-8.4V, with a 20cm high-sensitivity antenna, 16.5g weight, and 43×30×15mm size. The limitation is its role: ER8 is still a receiver, not a handheld transmitter, and its stated use centers on fixed-wing models. Choose it for a fixed-wing build organized around eight servos; choose ER4 instead when a compact four-channel model is the priority.
RadioMaster RP3 V2 ExpressLRS (ELRS) 2.4Ghz Receiver [RM-HP0157.RX-RP3-V2
RP3 V2 is the receiver to focus on when signal-handling features are the deciding detail. It combines antenna diversity, a built-in TCXO, an LNA, a PA, two antennas, Wi-Fi updates, and a stated 500Hz/F1000Hz refresh figure. At $22.49, it occupies a middle position among the receiver choices while remaining separate from the $74.99 transmitter role. Its limitation is its power requirement and hardware role: RP3 V2 is a 2.4GHz receiver with a listed 5V working voltage, not a controller. Choose it for demanding FPV or long-range use where antenna diversity matters; choose ER8 when eight servos are the deciding requirement.
Jumper T20 Radio Controller Transmitter ELRS for RC FPV 2.4GHz(READ DESCRIPTION
T20 is the only handheld transmitter in this group, and its full-size gimbals in a compact form could suit someone who specifically needs pilot-side control. At $74.99, it is marked used. The decisive limitation is explicit: the right gimbal needs cleaning with alcohol or may need replacement, and a slight delay is reported on the roll axis. That makes repair work part of the buying decision rather than a minor footnote. T20 is an ELRS 2.4GHz radio controller for RC FPV, but a transmitter cannot substitute for a receiver installed in the model. Choose it when a controller is the missing piece and you are comfortable addressing the gimbal issue.
Final recommendation by use case
- Small aircraft, boats, or cars: Choose RadioMaster ER4 for its compact receiver design and four-channel format.
- Fixed-wing builds: Choose RadioMaster ER8 when the airframe's servo layout matches its eight-channel format.
- Demanding FPV or long-range signal focus: Choose RadioMaster RP3 V2 for its antenna-diversity and built-in-TCXO features.
- Pilot-side control: Choose Jumper T20 only when a transmitter is needed and the used gimbal condition is acceptable.
If the decision is between a receiver and a transmitter, do not treat them as interchangeable: ER4, ER8, and RP3 V2 serve the model, while T20 serves the pilot.
