Mini-Z Radio System Summary
27Mhz AM
Mini-Z started with 27Mhz AM system using the KT-5 radio. The problems were well known. Once there are a few cars on the track, there are major interference issues. On some corners of the track, the car would just sit there and not move. The trick is to speed thru those sections of the track, and don't crash there. The response was slow. I estimate it to be 15ms.
AD Band
AD Band was a replacement board and module to be used on KO Propo radio. It worked great except every 15 minutes it would shut down for no reason, and the car wouuld stop. You have to turn the car off then on again to reset the system. There was an AD Band knock off in Asia. Unfortunately, that one also copied the shut down flaw.
ASF 2.4 GHz
This is the radio that finally solved the interference and shut down issue. ASF stands for auto select frequency. But, and there is always a "but", there was a built in delay for reverse. In mini-z, you crash often, and have to back up often. That reverse delay was a handicap. The KT-18 radio came out before the KO Propo module, so people had to run with the Kyosho radio for a while. It was actually quite a good radio. The reverse delay issue was always there until Kyosho came out with the MR03 that has an option to eliminate the reverse delay. Finally, everything was right with the world, or at least Mini-Z world.
FHS and FHSS 2.4 GHz
FHS stands for frequency hopping system. The FHS is a budget radio. It came with the MR-03S or MR-03S2 sport series. The KT-19 radio is not compatible with ASF radio. The antenna is blue to differentiate it from ASF. The quality of the board is very poor, and unreliable. FHS is not recommended. Get the FHSS instead.
FHSS was the next version of FHS. The radio is KT-531P. These come in the current MR03 (RWD) and MR03-F (FWD) readyset. This revised version has a name change, and corrected a lot of the issues with FHS. Is analogus to Nikon changing the camera name from D600 to D610 when they corrected the oil issues on their otherwise ground breaking full frame camera.
This system can use the upgraded Syncro Touch KT-432PT 
and the basic Syncro KT-531P shown above. Both radios are compatible with both
FHS and FHSS. The FHS and FHSS systems seems to be an entry level system that
has no upgrade path beyond KT-432PT. No brushless is avaliable with this system.
Higher end radio is not compatible with this system.
MHS 2.4 GHz
MHS stands for Mini-Z Hybrid Spread spectum system. Is supposed to be 4x faster than ASF. It has red antenna. This is the highest quality system for Mini-Z. They are used on the MR003VE with brushless motor.
Kyosho EX-6 shown above can control both the older ASF and this new MHS. This MHS board can also be controlled by the old ASF transmitter and the new MHS transmitter.
Upgraded radio, KoPropo EX-RR 
and the modular EX-2 
also
can control MHS, and is a professional radio.
PN Racing Radio System
V2 RC Board - Spektrum DSM2
Just as Kyosho is wrapping itself around the axel with new radio system after radio systems that are not compatible, PN Racing came up with a universal board for the Mini-Z. It uses the popular Spektrum DSM2 surface radio. The board comes with PN's own high performance 2x2 MOSFET. Settings can be programmed using either a PC or an Android phone using bluetooth with the PN Racing Bluetooth ICS Adapter.
The PN Racing PNR2.5W chassis is desiged around both the PN board and Kyosho board. Now you can have an almost complete PN Racing Mini-Z.
