??? 07/12/05 01:09 Read: times |
#97110 - quote from my previous post Responding to: ???'s previous message |
If there is no proper reference a short could assume any potential tip, ring, or something in between from the perspective of your selected input point so it is difficult to imposible to define the led states from this snippet your reference must be defined and its relationship to this "tester" clearly shown before anyone can properly figure the correct led response for a given circuit condition. Here in Canada You can not connect market even a tester for the phone system unless it is an approved device. Well you can but you do risk negative results. What is the value of a piece of test equipment that is not robust enough to survive under all anticipated line conditions. If you make 10,000 pieces and may save a $1 on each that is a reasonable goal to strive for. But on a one off tester that must work and that that costs $2 for parts and $100 in labour to make saving $1 on protection seems questionable economy. Terry |
Topic | Author | Date |
First:Wiring Error Detection! | 01/01/70 00:00 | |
It depends | 01/01/70 00:00 | |
First observation | 01/01/70 00:00 | |
First observation | 01/01/70 00:00 | |
Danger of surges | 01/01/70 00:00 | |
Sort of. | 01/01/70 00:00 | |
Sort of | 01/01/70 00:00 | |
Re: Sort of... | 01/01/70 00:00 | |
Phone line transients | 01/01/70 00:00 | |
Schematic of a simple filter | 01/01/70 00:00 | |
Research... | 01/01/70 00:00 | |
router | 01/01/70 00:00 | |
gas discharge tubes | 01/01/70 00:00 | |
GDT | 01/01/70 00:00 | |
Gas discharge tubes | 01/01/70 00:00 | |
Oh dear... | 01/01/70 00:00 | |
Gas Tubes | 01/01/70 00:00 | |
Or | 01/01/70 00:00 | |
Ring. | 01/01/70 00:00 | |
Where's Ring? | 01/01/70 00:00 | |
I say .. | 01/01/70 00:00 | |
Telephone systems | 01/01/70 00:00 | |
Telephone systems | 01/01/70 00:00 | |
tester | 01/01/70 00:00 | |
Yep Jan! | 01/01/70 00:00 | |
Even for testing not allowed | 01/01/70 00:00 | |
Line simulator | 01/01/70 00:00 | |
Another Misunderstanding Kai | 01/01/70 00:00 | |
misunderstanding | 01/01/70 00:00 | |
Jan | 01/01/70 00:00 | |
Confusion... | 01/01/70 00:00 | |
quote from my previous post | 01/01/70 00:00 | |
It's a current loop ... | 01/01/70 00:00 | |
Correction | 01/01/70 00:00 | |
ring? | 01/01/70 00:00 | |
Yes Jan! | 01/01/70 00:00 | |
Agreed | 01/01/70 00:00 | |
it explains a few things, though | 01/01/70 00:00 | |
Phone Line Ground | 01/01/70 00:00 | |
Not quite offtopic... | 01/01/70 00:00 | |
Alternative schematic | 01/01/70 00:00 | |
Just a simple comparsion !!!!!!!!!!!!!!! | 01/01/70 00:00 | |
please help me (telepone)![]() | 01/01/70 00:00 |