Read these Specifications to find out the differences between the different active transponders.
ActivePro Transponder
The ActivePro Transponder is the best-selling active transponder and is mostly used for cycling, skiing, inline skating, triathlon, mud races, motocross events and stand up paddling. It is suitable for most events where high-speed and high precision are required, within the limits stated in the specifications.
The ActivePro V3 Performance Transponder is the high-end solution for elite races and offers even higher redundancy.
ActiveBasic Transponder
The ActiveBasic Transponder has less precision than the ActivePro transponder but is significantly cheaper. It is mostly used for large events like mud races or large triathlons.
MotorKart Transponder
The MotorKart Transponder has the highest precision and can be used at speeds up to 120 km/h. It is mostly used for karting.
Technical Specification
Performance
Accuracy (Excluding Stored Passings)
When a transponder passes over a loop the transponder will receive multiple signals (hits) from the loop, the internal algorithm of the transponder then calculates the time which should be transmitted to the timing system, this time should be when the transponder passes the center line of the loop.
V3 Active transponders contain a new advanced algorithm for calculating exact passing time with the highest repeatable accuracy of any transponder, this accuracy is not so greatly impacted by variables in loop setup (width / power) or passing speed. V3 Transponders (excluding ActivePro V3 Performance) require a minimum of 2 hits from the loop to be considered a valid passing. The maximum number of hits reported by a V3 Transponder for a regular passing is 99 hits.
| Transponder | Accuracy | Reaction Time | Internal Resolution | Passing Resolution |
| ActivePro V3 Performance / MotorKart V3 | 0.004s | 125ms | 1/1024s | 1/2048s* |
| ActivePro V3 | 0.004s | 250ms | 1/1024s | 1/2048s* |
| ActiveBasic V3 | 0.2s | 500ms | 1/1024s | 1/2048s* |
| ActivePro V2 | 0.01s | 250ms | 1/256s | 1/1024s |
| MotorKart V2 | 0.004s | 125ms | 1/256s | 1/1024s |
| ActiveBasic V2 | 0.2s | 250ms | 1/256s | 1/1024s |
*Only applicable when using Ubidium
Accuracy: The repeatable accuracy of the passing time calculated by the transponder, if 2 transponders are recorded with a difference greater than the accuracy then the order of passings will be correct.
Reaction Time: The maximum time for which the transponder will wait for a stronger loop signal before transmitting it's passing. Lower reaction time = faster transmission of data.
Internal Resolution: The resolution of the transponder's internal time base.
Passing Resolution: The precision to which a passing is calculated.
Store Mode
Store mode allows the transponder to record the time at which it passes a loop in the internal memory, this is actually achieved by calculating the time since the stored passing and as such relies on the transponder's internal time base.
ActivePro (+Performance) / MotorKart V3
The internal time base of every V3 transponder is calibrated during production to provide a clock accuracy of +/- 10ppm.
Additionally the stored passing times are also calculated using a temperature compensation, as particularly at low temperatures there can be greater drift. The optimum working temperature is 25°C.
The result is a time with a maximum drift of just 0.036s per hour, across the transponders working temperature range.
ActivePro / MotorKart V2
The internal time base of the transponder is dependent on the callibration at the time of manufacturing the internal oscillator. No temperature compensation is applied to the calculated times.
Continuous / Exit Passing
When held over a loop for a prolonged period of time V3 transponders generate additional continuous passings and an exit passing with greater precision than previous versions.
Continuous passings will be sent every 5s after the initial passing is generated by a transponder. These can be identified by a hit count of 254.
Exit passings are sent when the transponder leaves the field of a loop after being within the field for a minimum of 3 seconds. The Exit passing is identified by a hit count of 255.
Exit passings are generated with accuracy according to the type of transponder.
ActivePro V3 Performance: 0.02s
ActivePro V3: 0.1s
ActiveBasic / MotorKart V3: 0.2s
Sensitivity
V3
To ensure maximum accuracy of passings the sensitivity of transponders is adapted during a passing.
Whilst awaiting activation from a loop the sensitivy of transponders is equal to Active V2 transponders. After the first loop packet is received the sensitivity will be increased, this effectively increases the detection range / height of the transponder, which will then continue to observe the loop packets as normal.
Once the transponder leaves the field of the loop the sensitivity will again drop to normal levels.
This increase in sensitivity helps eliminate a passing being generated too early, particularly when worn on the ankle as transponder may move through the field of the loop.
The impact of this can be seen when testing loop detection height - once a transponder is activated by a loop it must be moved much further away to leave the field of the loop. The additional range can be as much as 50cm.
Overlapping Loops
It is always advised to maintain a minimum distance between 2 loops equivalent to maximum speed in km/h divided by 10, in meters. e.g. 60km/h = 6m
V3
Active V3 transponders can internally handle loop data from 2 separate overlapping loops. Whilst observing 2 loops the transponder will choose when to switch from the first to second loop and a passing will be generated for both loops, the accuracy however may be impacted when loop fields are overlapping.
V2
Active V2 transponders cannot handle overlapping loops and such instances can result in loss of data from one or both loops.
2.4GHz Communication
RACE RESULT Active transponders use 2.4GHz to transmit their passing data to the Active system.
2.4GHz Transmission
When data is transmitted from a transponder to the Active System it also expects an acknowledgement from the system, if this acknowledgement is not received then it will continue to retry sending the data.The rate of retry varies with different transponder types, but all follow the pattern of several faster initial retries then with exponentially slower retries until the maximum retry count is hit. If this still fails then the passing will be automatically stored on the transponder (ActivePro / MotorKart only), the same as a passing received in Store mode.
ActivePro V3 Performance
When an ActivePro V3 Performance is activated by a loop it will first send a pre-warn packet via 2.4Ghz, this can be used as an alert that a participant is approaching, useful when displaying data as soon as possible is important. This is not normally used or shown in RACE RESULT 12.
The ActivePro V3 performance also has the fastest and highest rate of retries of any transponder type using the Quad Channel Backup as described below.
Note that when battery is 2.5V or lower and temperate is -20°C or lower the output power of 2.4GHz will be reduced to avoid drawing too much power from the battery.
ActiveBasic / ActivePro / MotorKart V3
Since most passings are successfully transmitted to the active system on the first try and with the improved 2.4GHz antenna of V3 transponders, the first attempt to transmit data is done so at a reduced 2.4GHz output power. Similar to the ActivePro V3 Performance the output power will also be reduced when the battery level is <=2.5V and temperature is <= -20°C.
If this first try does not receive a successful acknowledgement then it will be immediately followed by a retry at full power, after which the transponder will continue to retry as described above.
This logic provides significant battery saving over V2 transponders, however it may result in a lower average 2.4GHz RSSI since passings received on the first try were transmitted at a lower power.
If the first try fails then this does not count towards any warnings (NoAck) in the passing data.
Note that the retry logic for ActiveBasic V3 is slower than both the ActivePro and MotorKart.
ActivePro / MotorKart V2
The V2 range of ActivePro and MotorKart also send the pre-warn packet (as described in the ActivePro V3 Performance).
These have a slower rate of retry than V3 transponders and without the reduced power first try.
ActiveBasic V2
The ActiveBasic V2 has the slowest rate of retry with no pre-warnings.
2.4GHz Backup Channels
Each 2.4Ghz channel contains both a primary and backup frequency which helps improve 2.4GHz communication, particularly in environments with high noise / interference. Check Active System 2.4GHz Frequencies to understand the individual frequencies used.
ActivePro V3 Performance - Quad Channel Backup
As the performance version of the ActivePro V3 is aimed at providing the fastest and most reliable possible data transmission this includes a Quad Channel backup for 2.4GHz communication.
With this there are 4 pairs of channels 1/2, 3/4, 5/6 and 7/8, on which the transponder will attempt to transmit data on both the primary and backup frequemcy for each channel in the pair.
To make use of this a second system can be setup on the alternate channel of the pair, this can be with or without a loop. If connecting a loop to the second channel backup then there should be a sufficient gap between the two loops to prevent interference.
e.g. a primary finish is setup with the loop set to CH1, a second system is setup 5m after the primary on CH2 with no loop connected. Loop ID in this case is not important.
The passing data received will contain the Channel and Loop ID of the loop on which the transponder was activated - in this case the device ID should not be used as a unique identifier.
V3 / V2
All V2 and V3 transponders use a dual channel backup for 2.4GHz communication, with this the frequency will switch between the primary and backup frequencies of the channel.
When using a decoder with and Active Extension the V1 Legacy Mode of the system must be set to AUTO or OFF.
V1
With V1 transponders the 2.4GHz transmission is only on a single frequency. When using V1 transponders either alone or as part of a mixed population (V1/V2/V3) with a decoder and Active Extension then the V1 Legacy mode must be set to AUTO or ON. When the system detects a V1 transponder then the auto-channel switching will be disabled until the system is rebooted.
Active devices with FW version 2.6+ do not support legacy mode and should not be used with V1 transponders.
Tracking
Tracking mode is available on ActivePro V2 / V3 and MotorKart V2 / V3 transponders to be used with RACE RESULT Track Boxes.
Tracking mode does not use a loop setup for recording passings but instead relies on the 2.4GHz of the transponder to broadcast a "Trackping" packet. These packets are detected by the Track Boxes in order to calculate a passing time.
Status / Warning Flags
The passing data transmitted by the Active Transponder also includes 2 fields which help flag potential issues with the transponder or your timing setup.
Warning Flag
The warning flag is a single bit which is either 1 or 0, where 1 represents that a warning flag has been triggered on the transponder. The warning flag will always only be sent with the next passing and will then be reset, it will only be sent again if the same or another warning is triggered. Thus warning flags are always to be considered from the LAST passing recorded. A passing in this regard is considered a passing from Ubidium, an Active Extension or a Loop Box.
V3
The warning flag is used in combination with the Wake Up Counter (WUC) to indicate the reason for the warning, it may be difficult to ascertain the reason for a warning flag with the first passing but if the warning flag is triggered during the event then this is more reason for concern.
The following combinations are possible:
Warning Flag Set / WUC + 1 (regular passing): Either the transponder was woken up from Deep Sleep mode or the transponder detected high noise and entered Noise Suppression Mode. During an event a transponder should not enter Deep Sleep and so it can be assumed that this is a high noise warning.
Warning Flag Set / WUC + 2: High RX Error count - the transponder could not decode the loop data correctly.
Warning Flag Set / WUC + 5: Very high noise detected - the transponder entered Noise Suppression Mode but was still activated by high noise.
Warning Flag Set / WUC + 10: Transponder rebooted - please contact RACE RESULT.
V2
The warning flag is only used to indicate when a transponder was woken from Deep Sleep mode on V2 transponders.
Battery
The RACE RESULT active transponders report their battery level in the timing module with every passing.
It is not possible to determine the exact voltage brand new transponders should display, since the voltage depends on a number of factors, including temperature, but it should be above 2.7 V.
After a couple of years of usage, you should start monitoring the battery level of your transponders.
We do not recommend using transponders with a voltage of 2.3 V and below. The battery cannot be replaced, as the transponders are sealed and they would not be waterproof anymore after being opened. Once the battery is empty, you will need to buy a new transponder.
The discharge curve of the battery gets very steep at the end of life, at 2.2 V it is almost empty. Theoretically, transponders can work down to 1.8 V, but we cannot guarantee reliable operation, especially when used cold.
If you have transponder which you suspect are on low battery then read our guide on Active Transponder Battery Testing.
Technical Specification Comparisons
Active Chip Holder
The Active Chip Holder is mostly used for the MotorKart transponder to attach the transponder to a kart and to ensure that the transponder is not in direct contact with metal. There are three ways how to attach the holder:
- Use one of the O rights to attach it to a pipe.
- Feed a cable strap through the holes.
- Use a screw.
Active Transponder FAQ
Active Transponder Mounting Information
Active Transponders can be worn in different ways. When fixing to a bike or car, we recommend using the Active Chip Holder to separate the transponder and any metal parts which may impact the transponder activation. The Transponder could also be tied in the shoelaces or even fixed to bibs using adhesive strips.
When used on a velcro strap, we recommend fitting them on as depicted with the transponder code facing outwards and the strap not covering the transponder.
Active Transponder Rentals - Stickers
The stickers attached can be applied on the transponders to facilitate their distribution.
These eco-friendly stickers are compatible with inkjet and laser printers, and dissolve in water.
Please note that according to the rental agreement, the transponders must be returned sticker-free and sorted
in their initial order.
Please do not use any other kind of stickers. The print template can be downloaded below