[Coco] An X-10 usage for the Direct Connect Modem Pak

[K. Pruitt]

If I pursue this modification and go ahead and just install the CM17A in to 
the DC Modem Pak or at least a well-grounded DB9 port wired for the CM17A, 
that would leave most of the electronics in the pak just sitting there 
working but not really ever doing anything other than wasting energy.

That Marty Goodman modification is looking better all the time. I'd just 
hate to needlessly screw up one of these paks and Marty's mod is really 
outside of my current skill level.. I got them for $5 a piece back in the 
mid 90s, so they were cheap enough to screw up. But now they are becoming 
rarer. Still essentially useless in their current state, but still too rare 
to needlessly trash.

Guess I'll just let it percolate on the back burner and go back to messing 
around with the ol' reliable (sorta) RS-232 Pak.


----- Original Message ----- 
From: "George Ramsower"
Sent: Monday, August 17, 2015 8:27 PM
Subject: Re: [Coco] An X-10 usage for the Direct Connect Modem Pak


>  Phone lines are unbalanced. The means there is no ground. The tip is + 
> and the ring is - . This protects the phone company and the same is true 
> on all broadcasting audio lines and a heckuvalotta of other electronics.
>  If one device has a different ground potential than the other, a balanced 
> circuit is necessary.
>  You can't win this scenario. Play it safe, ground both phone lines to be 
> safe or use another connector where the phone jack was/is.
>  Never assume no one will plug it into a phone jack. However, since it 
> most likely will be used by the person who can modify it for your purpose, 
> it's not likely they would connect it to a phone line. But in time... 
> memory fades or the ownership can change. I expect anyone that buys this 
> setup, would not know.
>  My guess is that if someone was lucky enough to get MY coco stuff, they 
> would not even know what to do with all the mods I've made to the 
> "system". The coco itself is basically stock but all the plug-ins are not.
>  If I pass away, all this would end up in a recycling center. Even my 
> brother wouldn't want it and wouldn't know where to sell it, if he had the 
> time.>>> recycle bin.
>  I only personally know of a couple people that even vaguely remember a 
> Coco.
>
>  Consider all this dumb stuff. I don't, because I know after I'm gone... 
>  >>> recycle bin is where it's going.
>
> George R.
>
> On 8/17/2015 10:00 PM, K. Pruitt wrote:
>> I think the Tip line functions as a ground. Well at least in regular 
>> phone systems. I'll take it slow. I'd hate to fry a CoCo.
>>
>> ----- Original Message ----- From: "George Ramsower" Sent: Monday, August 
>> 17, 2015 7:49 PM
>> Subject: Re: [Coco] An X-10 usage for the Direct Connect Modem Pak
>>
>>
>>>  You will have to cut the phone line pair and use one or both of those 
>>> wires for a ground. The DTR and CTS lines do need a ground. Then, the 
>>> phone jack is totally useless for anything else. However, using the two 
>>> center pins as a ground will eliminate the possibility of destroying the 
>>> pak and the possibility of killing a coco.
>>> George R.
>>>
>>> On 8/17/2015 9:42 PM, K. Pruitt wrote:
>>>> I used my zap utility and just changed the addresses to look at the DC 
>>>> modem pak. I just didn't change it everywhere.
>>>> Honestly I'm surprised it worked at all.
>>>>
>>>> Only two of the 4 wires in that 4 wire connector are even used. Yellow 
>>>> and blue are unused. So they are wide open for use and can be easily 
>>>> jumpered to the DTR and RTS pins on the 6551. I'm fairly certain even I 
>>>> can pull this one off. Not quite mod-free, but a really easy mod.
>
>
> --