and the head is placed and painted in mat black, to disguise it..

and in place..the only head ache that i feel with the ribbon wires..aren't good quality..but it will last up to my speed test..

now the second question..." tape recorder heads - sounds ingenious - but as far as I recall
      the tape has to actually physically contact the head - surely your
      tyres are not physically contacting the head."  so you are absolutely right..  NOOO..you are very wrong..i was making, still making electric guitars, for my friends, and students, with tape heads as pick ups..it gave us a very Hi Fi proportional stereo outputs all the while. a AMORPHOUS type head gives even more output. a METAL head also play a good role..here i am posting some pictures and a good video, for you..
i am using tape heads as sensors even on my GUN BARREL STABILIZER, as ventral and lateral...precisely..
the figure 6 and seven shows a toy wheel, attached to a gear box via a ESC, and taped to a battery to avoid displacing..you can see a magnetized metal strip is attached to the rim of the wheel, to face with head..

next figures showing a tape recorder itself, and removed head with simple wires..then the power amp, with an euqlizer to alter the frequency..

showing the tiny woofer and power supply..now experiments begins..
you can see i placed the head near to the wheel, facing to the mettalic strip, not in contact, but still pics up the energy.we can feed this pulse after filtering it, and can use for any purpose..

where..? yes no photos..but you must watch this video..i shot this for you..

so can use this pulse after filtering for any needed purpose..encoding..decoding..sensing..pulse..detection..traction..braking..control..speed base motor control..follows..
no any some thing circuits will work..but it must be precise..so i will post all used circuits on this car after full work, and after my speed test..with new motor..sure..

Kalyan..we can use any MOSFET or PT, according to our needs and i never sticks on on one..but always puts a safer margin above the actual needs..

Roopesh - very nice

keep it up

Sai..never consider my postings as boasting, or rage or demo..was sharing my knowledge..and may be this is why, my native people always call me as "Vattu Case" means mad guy..but sad to hear that..as modellers we must go far beyond our imagination and creativity..maximum..giving up..its not our option..i will add a good video of my song play, with my hand made guitar, used the tape heads as pickups..its too nice..

Hi Roopesh,
I am wating for your car video, 53Km. Please post that video ..

Hi Roopesh,

Its not seems 53Km/h, how you have measured its speed ??

Gb, its not a speed test video. its first  drifting video.speed was tested on our old unused strip, but was poor surface, and speed was measured by Garmin, GPS. waiting to take her to a nice ground, after fixing the new motor, and rated at 11.1 volts, 2500 mA. hope fly..

so its not run @ 53Km/h,...please correct me if I am wrong... ..Also tested mine outside...and dont know its speed...but it run good  .

Gb..its very appreciable effort, indeed.. :thumbsup:and she ran over 53 Km/Ph. but the ground clearance of my car is too low.so she slows up now and then as she dribbles over the stones. and the 7.2 volts battery was running out fast. but now, i replaced with new reworked motor, added two high amp, relays,all with 11.1 volts 2500 mA LiPoly battery.waiting for my friends, to cover the video, and GPS, but looking for a good ground,within 100 meters at least.after that i will check it with twin brus hless..need a little time..