Last one, I promise.

I just applied 1.4 amps in that coiled 4 wires in parallel, it just
dropped 0.13 Volts, what gives me a total resistance of 0.0975 Ohms in
6ft cable.  A total power dissipated of 30mW per ft is acceptable for a
800mA 15 minutes glorious demo to a customer.  For sure Robert, for the
series production I would not go to BellSouth handset coiled flexible
cables, a heavy cable literature is the best choice, I agree with you.
But requiring the cable at 10:00am to a demo at 01:00pm is something
that no cable company could delivery as fast as the headset cable, not
from RadioShack, but from K-Mart... :)

When somebody says to me "YOU CAN NOT DO IT", but he doesn't know
exactly why, it sounds to me one of two possibilities:

1) His knowledge is suspected, so I would delight myself exploring his
information resources.

2) However, if this guy is in militar clothes, pointing a machine gun to
me, and there are tanks and helicopters all around, then I am in a
military dictated country, I would delight myself to the first
international airport.

...next time at RadioShack I would be listening my portable CD player
with earphones... :)

Wagner.

"Robert K. Johnson" wrote:
>
>         I wasn't aware that an EE degree was a requirement for a sales positio
n at
> Radio Shack... Seems to me that the sales persom was trying to do him a
> favor...
> BTW Telephone Coiled handset cords are probably the poorest choice for ANY
> load greater than 50 MA. Typically they are composed of small flat (ribbon)
> conductors wrapped around a fiber filler... At least this is the experience
> of this 53 year old Engineer... REALLY! why would anyone oin his rifgt mind
> expect a salesman at an appliance store that stocks a limited number of
> parts to be an expert on all parameters of the materials they sell...
> Suppost next it is justifiable to be angry with the person for not knowing
> the 1/2 power beamwidth of every led that the store stocks. In My
> profession I first detirmine the wire that is required (most wire catalogs
> are free if not directly on the internet) and then it is a simple task to
> evaluate various possibilities... it seems to me that a 100 % margin for a
> wire that needs to be flexed repeatedly is a very poor margin. That is
> however a matter of experience and preference... But 2 to 3 amps would be a
> better choice...