gondola1988 ww.ebay.com/itm/20-HO-SCALE-RED-FLASHING-3MM-LEDS-WARNING-BEACONS-FREE-RESISTORS-FOR-12-V-/360449757806?pt=Model_RR_Trains&hash=item53ec7ad26e#ht_3733wt_1270 Try this its for 20 of them,Jim.
ww.ebay.com/itm/20-HO-SCALE-RED-FLASHING-3MM-LEDS-WARNING-BEACONS-FREE-RESISTORS-FOR-12-V-/360449757806?pt=Model_RR_Trains&hash=item53ec7ad26e#ht_3733wt_1270 Try this its for 20 of them,Jim.
What a mess. Now it is clickable.
http://tinyurl.com/83zmej6
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
MrMick I am trying to build a FRED circuit using a 555 timer. Hoe do I tell which terminal ls 1 on the chip? It is a Radio Shack 555 timer built by Texas Instruments. I suspect that the ! termnal is onthe lower left end when reading Texas Instruments from the top of the chip, but I am not certain ( as thisis teh frist time I have tried anything like this). Thanks for any help. My searches of the Internet were fruitless.
I am trying to build a FRED circuit using a 555 timer. Hoe do I tell which terminal ls 1 on the chip? It is a Radio Shack 555 timer built by Texas Instruments. I suspect that the ! termnal is onthe lower left end when reading Texas Instruments from the top of the chip, but I am not certain ( as thisis teh frist time I have tried anything like this).
Thanks for any help. My searches of the Internet were fruitless.
No problem here. No idea on how you did your search. I use this search engine which does not track you like Google does.
http://privatelee.qrobe.it/search/?q=555+circuit
Store the below link in Favorites. This guy has a lot of good info.
.http://home.cogeco.ca/~rpaisley4/LM555.html
http://home.cogeco.ca/~rpaisley4/CircuitIndex.html
Thanks for help solving the problem for me; the TI "top" view and the idea of the dimple, both confirm what I thought was the terminal #1; thanks stevert and rrinker; (I had tried to find a 3mm blinking led, could only locate a 5 mm in the local RS's.) Thanks again, guys.
Pin 1 of most any IC is indicated by a dot or dimple, if not an outright mark like a small triangle or in some cases even the number 1.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Instead of all the additional circuitry required for the 555 timer, you can get red 3mm LEDs with built-in flashers, and I have seen some advertised that are even smaller.
Google is your friend:
TI 555 specs
Edit: More here.