T&L Publications

MrAl,

The M4 is a standard metric size as far as thread pitch is concerned. Should just need to determine length needed. Here's a link for a dimensions chart if that helps.
http://www.tribology-abc.com/calculators/metric-iso.htm

Steve G.

CeaSaR, Should work OK . My only concern is the output voltage loss across resistor R6. That's a 50% loss which might be OK if the device this is plugged into has plenty of gain to compensate. I would change R6 to 100K or use a buffer transistor to lower the output impedance of the circuit. Steve G.

MrAl,

If you have a tap and die set you could re-tap the nuts for 10/32 and 8/32 screws but that seems like a waste of time. At this point might as well just keep in a seperate bin marked "Dollar Store" size. You only payed a buck for em right? You get what you pay for.

Steve G

MrAl,

Assuming they are standard metric sizes I would just go down to Ace Hardware and find the matching nut in their metric bins. Are you suggesting they're some "off the wall" size that only works with the nuts supplied?

SteveG.

Correct. From the emitter of Q2 to the base of Q1

Steve G.

CeaSaR,

Got a chance today to tweek some of the component values. Here's the improved version with specs if still interested.

Cheers,
Steve G.

CeaSaR,

In my circuit you can adjust the gain by changing the value of the emitter resistor on Q1. A higher value will lower the gain.

Steve G.

dacflyer, If you decide to use common anode dual red/blue LEDs and a 4017 then the circuit below is one possibility. The outputs from the 4017 are normally low so all the blue LEDs are initially on. Just don't exceed the 10 ma current limit of the output pins. Would only require two 4049's to comple...

CeaSaR, The capacitor values will depend on the frequency of the signal and the input and output impedance involved. Some of the poor low end response might be from the microphone . 1000uf caps are extreme in this case. Below is a schematic that I have used for a mic preamp numerous times. It has a ...

laeeq,

Go to Google, type in "ULN2003" You will find everything you need to
know about this chip.

Steve G.

"Characteristics" on page 3 give the leakage current.
"Operation" on page 11 talks about leakage current which is normal.

Steve G.

Can't you just plug the event timer into the output of the inverter? It's 120vac correct, or am I missing something in your post?

Steve G.

MARK,

Short answer,yes. Data sheet shows simple connection as long as the power supply is a least 5 volts.

Steve G.

jimandy, Here's a simple three station setup using two conductors (coax). You didn't mention how the stations were getting power. Assuming battery power, you can use an additional switch for power as shown or possibly a momentary DPDT switch if available. Cheers, Steve G http://www.postimage.org/Pq1...

bena, Here's a circuit that might work for your application. Using a HTC550 monostable with a pulse width of .1 second duration. Circuit works with the components values shown in the schematic using an ordinary cadmium photocell as the sensor. R1 may need to be adjusted depending on the type of ligh...