[aprssig] APRS in-dash display

Greg D ko6th.greg at gmail.com
Sun Jan 17 16:35:30 CST 2016


Hi Travis,

My in-dash unit has a setting which automatically selects the camera 
when in reverse, or manually.  There's also an interlock that one can 
turn off, which I believe is for viewing DVDs (not a good idea IMO, but 
it's there).  So, it was just a matter of picking the right settings; no 
external bypassing was required.  The unit has a lot of features, which 
just about make up for its horrible user interface ergonomics.

Besides mounting another display somewhere on the dash (not possible for 
me), an alternative to using the in-dash display might be to swap out 
the factory rear view mirror for one that adds a backup camera / 
monitor.  There are a number of them on the market, some with integrated 
GPS / navigation, and one I saw even runs Android (touch screen on your 
mirror, really?).  Most seem to have two video inputs, one for the 
backup camera, one for DVDs, which could theoretically serve as the Pi's 
display.

Again, I am unsure why/if these are allowed, but they are widely 
available (Amazon, etc.).  I actually have one in the car, as getting to 
the back of the in-dash unit was initially thought to be a significantly 
bigger deal (like, take the dash apart) than it ended up being.  What I 
found was that the in-mirror display is hard to use in practice, due to 
two issues:  glare from the front window behind it, and the need to 
substantially change your eye's focus to look at the mirror instead of 
through it out the back of the car. The glare was supposed to be 
overcome by the mirror's self-adjusting brightness, but in practice I 
don't find that effective enough.  The focus thing might be just a 
matter of getting used to it, though anyone with bi-focal glasses will 
have a bit of a challenge.  But it is kind of interesting, as if you 
keep your long distance focus, the mirror part still works.  One 
signficant issue would be the legal implication of having the display so 
visible, especially at night. Mine comes on when I start, and I 
sometimes look at it while backing up (just to try it - the camera is 
taped to the rear window), but then turn it off and leave it that way.  
In hind sight, I probably wasted my money.

Greg  KO6TH

* - The newly introduced Chevy Bolt claims their rear mirror can be 
turned into a rear camera, and others are trying to use cameras for the 
side mirrors.  If these solutions start becoming common, the legal and 
ergonomic issues might get clarified.


KB5ILY - Travis W. Burton wrote:
> Greg,  Does the gear-shift have to be in Reverse to view that input ?  
> If so, how are you bypassing it ?
>
> On Sat, 16 Jan 2016, Greg D via aprssig wrote:
>
>> Hi folks,
>>
>> Picking up on a thread I started a while back...  Not sure if this 
>> will lead to something permanent or not, but I tought I'd give it a try.
>>
>> I got access to the back of my car's in-dash unit, and the video 
>> input connector.  It's meant for use with a back camera, which I 
>> currently don't have (though it's on the wish list...).  Found a VGA 
>> to RCA adapter box, and fired up APRSIS32 which was loaded on a small 
>> laptop. Here's the result:
>>
>> http://home.wavecable.com/~ko6th/aprs_dash_display.jpg
>> http://home.wavecable.com/~ko6th/aprs_laptop.jpg
>>
>> Given the difficulty, if not questionable legality, of controlling a 
>> GUI-based laptop while driving, I think the next steps need to include:
>>
>> 1.  Replace the laptop and VGA adapter with a Raspberry Pi.  VGA 
>> output is built-in, also much better power draw and small size. (The 
>> car is a sports car, so no room for anything bigger.)
>>
>> 2.  Replace APRSIS32 with YAAC (for Raspberry Pi compatiblity).
>>
>> 3.  Probably still need a keyboard for full control while parked, but 
>> add some fixed key switches tied to keyboard shortcuts for the common 
>> stuff while driving.  During the earlier exchange, Andrew figured it 
>> was a "simple" matter of a Java library to bridge the swtiches to 
>> keyboard shortcuts... Hope he's right.
>>
>> 4.  The Pi will boot itself when the car turns on, but I need a way 
>> to automatically safely power down the Pi when I turn the car off. 
>> Any ideas on this?
>>
>> Anything else I'm missing?
>>
>> Greg  KO6TH
>>
>>
>>
>> _______________________________________________
>> aprssig mailing list
>> aprssig at tapr.org
>> http://www.tapr.org/mailman/listinfo/aprssig
>>
>
> 73 de Travis KB5ILY / PG00041468
> 870-260-6068 (Phone)
> -- 
>     Travis W. Burton, NP, ESQ., KB5ILY (QCWA) & GROL / Arkadelphia AR
>                 President, DeGray Amateur Radio club, Inc.
>        EC - Clark County AR / SW Arkansas District Emergency Coord.
>                SATERN, ARRL Instructor & VE, AREC I, II & III
>                           W5YI Instructor & VE
>                       Internet: mailto:kb5ily at arrl.net
>          http://www.broadcastify.com/listen/feed/9877/web/?rl=rr
>                          WWW:  http://www.kb5ily.org
>                    GOD BLESS THE UNITED STATES of AMERICA
> Only he who Attempts the Ridiculous can Achieve the Impossible. (WILL 
> HENRY)
>                    Linux is my operating system of choice.
>
>                    Computers are like Air Conditioners,
>              they stop working correctly when you open windows.



More information about the aprssig mailing list