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

[George Ramsower]

  I caught one of my own mistakes in this post.
  Phone lines are BALANCED. An unbalanced audio line is quite different. 
The shield is usually grounded in an unbalanced audio line. A balanced 
audio line has no ground on the two wires and normally has no shield.
  On microphones, some use balanced audio lines but those two wires are 
shielded making it a three wire audio line.
  My dusty brain does that from time to time

On 8/17/2015 10:27 PM, George Ramsower wrote:
>  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" <georgera at gvtc.com>
>> To: <coco at maltedmedia.com>
>> 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.
>
>