Stupid Motorola Trick #1,000,451: Using a W3 head with a MCS

[motorola_otaku]

I'm not joking. It works.. sort of.

What you need is the straight-through cable from a regular GMN6147 MCS mic (the one that looks like a Jedi/XTS speaker mic and has 3 side buttons). Plug the mic end into your HMN4044 W3 head, the other end into the mic jack on the MCS, and away you go. I tried it on a Model 1 MCS and the 3 "dot" buttons underneath the display correspond to the 3 side buttons on the MCS mic, the VOL button corresponds to the channel selector, and the left top button corresponds to power. Everything else just bonks. It displays channel text on the top display line, and even correctly displys the little |->| symbol on simplex channels. And yes, it TXes and passes mic audio just fine.

Operation is flaky, though.. sometimes the display on the mic loses sync with the control head display, sometimes the radio won't complete a self-test and freezes up, sometimes the HHCH display will freeze up on SELF TST while the radio boots normally, and other fun stuff.

Have fun. Personally, I'm curious to see if it displays both lines of CH text when used on a model 3 radio.

[alex]

Keep in mind for the most part, all the Motorola Radios (maybe except for the new 05 stuff) use SB9600 to communicate, and have button addresses that are probably very similar. So when you hit a button, SB9600 goes, oh look, button 123 and it's state is x. Much like when you throw the radio in to the display/button test, and you see 1/0, etc. This is also why a W7 head when placed on a W9 radio, will still work and function, your just missing a couple of keys that aren't physically present on the head.

It doesn't really shock me to learn that this is possible (although neat). I would probably put some money on the table that the model III MCS2000 would in fact show two display lines because of the addressing on the screen. If you had a way to muck with the firmware in the W3 control head and re-assign buttons based upon a model III configuration of the radio, you more than likely could have a W3 MCS2000.

Although expensive - the MCS2000 style jedi mic head with a keypad on it can be used on a model I or II radio to act as the unlimited keypad and manually punch in MDC ID's and such for paging. Thinking about it more - I forget if you can enable unlimited calling in a model II/I mcs2000. Eh.

-Alex

[resqguy911]

Wonderful. So the HHCH works on an MCS but not an AVA.

[mr.syntrx]

Keep in mind for the most part, all the Motorola Radios (maybe except for the new 05 stuff) use SB9600 to communicate, and have button addresses that are probably very similar.

I understand the new heads use a similar protocol operating over CANbus.

[motorola_otaku]

Wonderful. So the HHCH works on an MCS but not an AVA.

Like Alex pointed out, the HHCH is looking for SB9600 data which the stock AVA doesn't provide. Most likely (speculation ahoy) the AVAs that DID support an Astro HHCH had a different firmware load that DID provide SB9600 data to the mic jack.

[bellersley]

Unfortunatly, the one person who claimed to get a W3 working with an AVA wasn't smart enough to document anything.