Ron...There will be 2 wires from the board 1 will be ground and the other will be the one that has to momentarily connect to the ground to enable the board. The led can be powered by any source that I will supply.
Rich --- Ron Wright <[EMAIL PROTECTED]> wrote: > > Rich, > > Now you are talking about some power for the light. > Best use an LED > that draws low current, 5 ma. > > Not knowing what you are connecting to, it might > have enough current to > drive the LED. > > Are you simply grounding an input, appling power to > an input, etc. Do > you have details of what you are connecting to??? > > 73, ron, n9ee/r > > > Ron Wright, N9EE > > 727-376-6575 > > MICRO COMPUTER CONCEPTS > > Owner 146.64 repeater Tampa Bay, FL > > No tone, all are welcome. > > > > > On Mon, May 12, 2008 at 2:29 PM, Rich Summers > wrote: > > Ron...That is exactly what I could use as long as it > had some type of light to let the person know that > the > board has been enabled. > > Rich > > --- Ron Wright < [EMAIL PROTECTED] net > <mailto:[EMAIL PROTECTED]> > > wrote: > > > > > One can get push button switches that latch on > when pushed/latch off > > when pushed again. IF you want just digital mode > while switch is > > pressed then no problem. If you want to make sure > the radio stays in > > analog until commanded requiring the op to hold > during digital then a > > momentary switch can be used. > > A "flip flop" or D-Type latch like the 74LS74, a > 30 years old part, > > can be made to work, but unless you are driving > with some electronics > > to automatically change between digita/analog it > would be over kill. > > Also sounds like the latch is still going to a > switch to flip the > > flip-flop and with switch bounce one would need a > de-bounce circuit. > > A 74LS123 one shot is good for this. However, > still over kill. We > > could also do with a CPU like the PIC processors, > etc. Fun to work > > with and would learn something, but WAY OVER KILL, > hi. > > A switch is easy no brainer here unless there are > othe issues. > > Requires no power, just some wiring and about > every type and size of > > switch one can imagine is on the market. > > 73, ron, n9ee/r > > > > > > > > On Sun, May 11, 2008 at 8:22 PM, Rich Summers > wrote: > > I can't use a toggle switch because the contact to > enable the scramble > > board needs to be momentary to turn on the board > and then a momentary > > contact to switch off the board. This contact will > be using an enable > > wire from the board and another wire that is a > ground. I think a flip > > flop MAY be the way to go. I was also wondering if > there is a push > > button switch that has 2 spst contacts? Thanks. > --- MCH < [EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]> <mailto: [EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]> > > wrote: > >> For that matter, why not just a toggle switch? > Joe M. Rich Summers > >> wrote: > >>> I need to build a simple circuit to enable a > > voice > >> scrambler in a radio. > >>> What I need is a momentary contact by pressing a > >> button so that the > >>> activation lead goes to ground and when this > >> happens I need an led > >>> indication that the unit has been activated. I > > also need the led to > >>> turn off when the button is > >> pressed again. This > >>> deactivates the board and the radio returns to > >> normal mode. > >>> I need this in a small box. Does anyone have a > > circuit I could build > >>> for this > >> particular application? > >>> > >>> Thanks, Rich > >>> > >>> ------------ --------- --------- ------ > >>> > >>> Yahoo! Groups Links > >>> > >>> > >>> > >> > > > > ____________ _________ _________ _________ > _________ _________ _ Be a > > better friend, newshound, and know-it-all with > Yahoo! Mobile. Try it > > now. http://mobile. <http://mobile.> yahoo.com/ > ;_ylt=Ahu06i62sR > > 8HDtDypao8Wcj9tA cJ > < http://mobile. yahoo.com/ ;_ylt=Ahu06i62sR > 8HDtDypao8Wcj9tA cJ > <http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ> > > > > > > > < http://mobile. yahoo.com/ ;_ylt=Ahu06i62sR > 8HDtDypao8Wcj9tA cJ > <http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ> > > > > > > > > ____________ _________ _________ _________ _________ > _________ _ > Be a better friend, newshound, and > know-it-all with Yahoo! Mobile. Try it now. > http://mobile. yahoo.com/ > ;_ylt=Ahu06i62sR 8HDtDypao8Wcj9tA cJ > <http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ> > > <http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ> > > ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
