[Elecraft] operating HF / KX3 in a Tesla Model S

[Lyle Johnson]

Hello Johnny!

You may need some filtering on the 12V power connector in the center 
console of the Model S.  The 12V battery is also quite small in the 
vehicle.  I'd be inclined to package an LiFePO4 battery pack and a 
charger for it and place it in the center console area, powering the 
mobile rig from the LiFePO4 pack.  That will give you surge capacity for 
higher power should you desire it, probably make any necessary 12V noise 
filtering easier and limit the stress on the 12V system in the Model S.

For antenna mounting, you might consider adding a trail hitch adapter, 
and then mount the mobile antenna to that, using its bonding to prevent 
possible damage or modification to your vehicle.  In the U.S., such a 
hitch is made by Torklift (www.torkliftcentral.com then click through 
Ecohitch and Tesla Model S) and seels for under $400 plus shipping and 
installation. It is invisible when not in use.  I know a couple of Model 
S owners here in Tucson that have these hitches and are satisfied with 
their quality and durability.

73,

Lyle KK7P


On 10/19/16 7:45 AM, Johnny Siu via Elecraft wrote:
> Thanks Bill.  The fuse in the cigarette lighter is 15A.  I think only a 50 W amplifier is workable.
> 73
> Johnny VR2XMC
>
>        寄件人︰ Bill Frantz <frantz at pwpconsult.com>
>   收件人︰ Johnny Siu <vr2xmc at yahoo.com.hk>
> 副本(CC)︰ Elecraft Reflector <elecraft at mailman.qth.net>
>   傳送日期︰ 2016年10月19日 (週三) 10:15 PM
>   主題︰ Re: [Elecraft] operating HF / KX3 in a Tesla Model S
>     
> On 10/19/16 at 9:02 PM, elecraft at mailman.qth.net (Johnny Siu via
> Elecraft) wrote:
>
>> I am thinking operating my KX3 in my Tesla and have some questions:
>> 1.  Is it ok to direct drain DC supply from the cigarette
>> lighter socket since there is no ignition system in the Tesla?
> You will be drawing less than 4 amps, so the lighter socket
> should work fine. If you decide to add the 100W amp, then
> running dedicated wires will probably be the correct choice. I
> would want to know more about the 12V supply in the Tesla before
> running them. Perhaps the car manual has some advice.
>
>
>> 2.  The body of Tesla is aluminium alloy (if I am correct.
>>   How can I ground a mobile whip to the car body?
> Grounding techniques should be the same as for steel. Do be
> aware of the corrosion issues when different metals are in
> contact. Aluminium corrodes easily, so having a sacrificial
> piece of metal to protect the car body may be a good idea.
> Perhaps a piece of aluminum bonded to the car body with copper
> or brass bonded to it. (My electro-chemistry is a bit rusty.)
> Then that piece of aluminum will corrode and can be easily
> replaced. Also think about the materials for any screws/bolts
> used for the bonding.
>
> 73 Bill AE6JV