2022 JP new build part 4

[graham pipe]

With the tank nigh on finished I faced the dilemma of which control system to use – the wonderful Armortek modules or to go my own route.

As I was using 12 volt motors and the factory system runs on 24, the possibility that there might be a shortage of modules available following the sales of the new Panther G, plus the £1200 cost of same, I decided to use a hybrid system of my own making.

A pair of 40 Amp Robbe electronic speed controllers were selected along with a model boat mixer unit I'd had knocking about unused since my boat modelling days back in the 1990's. My 35 Mhz JR X388 8 channel programmable transmitter and receiver with which I previously used to fly model jets was dug out of hibernation and the program mixing functions set up to enable tank operation.

The sound system was looking to be problematic as, to my knowledge, the factory sound unit won't work without the matching motion packs. So, finding a full option Tamiya 1/16th Tiger 1 (missing 9 track links) on a local French website for only £74 struck me as being something of a bargain as I could use its DMD system for sound, gun motion and firing sounds.

Duly acquired, the small Tiger was fully operational so everything was rigged up on the JP for a test with the DMD connected into the receiver's steering and throttle outputs by a pair of Y leads. The redundant Tamiya speed and steering controller were left unconnected but powered up as all the other functions slave off it. A few adjustments in the menus to travel rates and mixing et voila, it all worked!

So, a 12 volt gel cell powers the tank's motion and gun elevation, a 7.2 volt nicad pack supplies the DMD unit (though will be running off the main 12 volt battery once I've stepped the voltage down with a variable or fixed resistor).

The transmitter is set up with throttle on the left stick (forward and reverse each side of neutral position), steering on the right, gun elevation/depression on the right stick in the vertical plane and, with full trim selected on the gun movement, a quick jab of the stick to max position gives machine gun fire upwards and main gun sound and recoil downwards. The left stick sideways movement controls the gun traverse. Sounds a little complicated but is really simple and well worth the £74. Anybody want a full option Tamiya Tiger minus its DMD?

The Tamiya speaker box whilst being loud, was very plastic sounding so a pair of 70mm square speakers were acquired and built into plywood speaker boxes who's slanting faces direct sound up and out of the cooling fan grilles.

The sound is good and very realistic but I may incorporate an amplifier and step up the speakers from 4 to 8 ohms. Time will tell.

One day I might replace this set up with a proper Armortek system but for the time being I'm quite happy with my budget hybrid. Certainly, the tank looks very empty inside when compared with models one can see on this site!

More to come in Part 5...

[Steve Norris]

Hi Graham.
Pm sent
Regards
Steve

[Chang]

Hi Graham,

Read through and enjoy all of 4 parts of your new built JP. The internal mechanism is an eye-widening to me.

So far I have only one question : Where is the main 12V ( and / or 7.2V) battery located?

Regards,
Lerh Chang

[graham pipe]

Hi Chang and thanks for the comments. Much appreciated.

The main battery sits underneath engine deck on an aluminium plate spaced from the hull floor on hex standoffs like the motor and radio gear plates. The DMD nicad pack which also powers the receiver by a BEC system lives adjacent to the big 12 volt gel cell.

Not sure of running duration yet as the vehicle has yet to drive. Am waiting for brother-in-law to help me lift it off the bench and get it downstairs when they stay with us for Christmas. Will hopefully be posting some video of it running once we get the hefty lump outside. My wife suggested I put boards on the stairs and drive it down... I think not somehow!!!!

[Chang]

The main battery sits underneath engine deck on an aluminium plate spaced from the hull floor on hex standoffs like the motor and radio gear plates. The DMD nicad pack which also powers the receiver by a BEC system lives adjacent to the big 12 volt gel cell.

Hi Graham,

Thanks for the above quoted answer, which does confirm my thought. Eager to see the following photos in part 5.
While possible, better keep the JP downstairs after testing (garage ). Believe me, you don't want to lift it back and forth each time, even with help.