[aprssig] Limitations of D700a

[Steve Bragg]

Kevin VA3SU wrote,

 > I plan to purchase a Kenwood d700a (at Dayton) <snip>
 > ... looking forward to seeing the new Hamhud V and I plan to look at it's features before I 
 > buy the Kenwood.

Kevin,

Thank you for considering HamHUD V; the HamHUD team is really excited about it, too.  But if you're looking to get an APRS rig right now, and you're not willing to wait a few more months, then you might better go ahead and get the Kenwood D700a at Dayton.  

HamHUD V kits will NOT, repeat WILL NOT be sold at Dayton this year.  There is a rumor going around to the contrary.  Close, but not quite.  We will only be showing the "demo board", with "demo" firmware, in order to get valuable feedback from our propective customers.  We WILL be taking orders for _HamHUD II_ kits, for people who already have a D700a/DR135t/TNC, and don't want or need the fantastic capabilities that HamHUD V promises.  Anyway, the plan is for HamHUD V kits (as well as fully-assembled units) to be available in the fall.  And don't forget, you *still* could connect the HamHUD V to your D700a.

 > It is a shame that Kenwood didn't make the firmware upgradeable, if it 
 > was the purchase of the radio would be a no brainer imho.

I keep hearing this from hams I meet everywhere, and that's a good thing.  There's a revolution brewing that the major ham radio manufacturers are doing nothing about.  A new generation of hams has arrived to LIKE to "tinker": they want to modify their radios, adjust things, try new modulation types, etc.  It's that whole "advancing the state of the art" thing.   Often, that means they need to change the radio's firmware to accomplish their goals.   I don't truly understand Kenwood's reasoning on locking down their firmware, but HamHUDs have been and always will be open source.

And Kenwood's reasons can't be of a regulatory nature.  The FCC recently clarified its position on open-source and software radio in the amateur bands.  They want to encourage them as much as possible, and put as few restrictions on firmware as possible.  It's sad that radio manufacturers can't see as clearly as a government bureaucracy!

 > So what cool features of APRS will I miss if I go with the d700a? 

Strictly speaking, none, because SmartBeaconing is not part of the APRS specification.  But SmartBeaconing produces tracking data far superior to fixed beacon rates, with lower QRM.  This is true even if the fixed-rate tracker uses PROPORTIONAL-PATHING (which HamHUD V will support).   But you can get SmartBeaconing by combining a HamHUD II (or V) with your Kenwood D700a.  You may want to buy both ;-)

Bob Bruninga wrote,

> For what it is worth, 85% of all mobiles that
> receive-and-display APRS in the mobile use the D7 or D700. 
> The HAM-HUD is the only other non-PC that also has a decoding and
> display system and it represents some of that other 15%.

The HamHUD team hopes to change that ratio ;-)

And note, the trademark (registered pending) is HamHUD, "H" (uppercase) "am" (lowercase) "HUD" (uppercase).
 
> To me while mobile, receiving and seeing what is around me on
> APRS is actually more important than transimtting... That's
> what APRS is all about... 

I could not agree more; desiring this awareness in my mobile station led me to develop the HamHUDs.
 
> They announced a possible new radio back at the Digital Comms
> Conference in September... It will be intreresting to see what
> they might be showing at Dayton?

It will be interesting to see what Kenwood will show at Dayton.  But unless they seriously reverse course in corporate policy, three things will remain the same:

1.  The firmware will be closed-source.
2.  The flash memory will NOT be user-modifiable (precluding open-source alternate firmware).
3.  They will not incorporate SmartBeaconing.

See-y'all-at-Dayton 73s,

Steve Bragg KA9MVA
"The HamHUD Guy"