[Reverie]

Hey all!

I've nearly finished a 41hz amp4 kit, but I've come across a pair of issues I could do with some advice on, and I can't seem to get the 41hz site to work for me.

If anyone can lend any advice, it would be greatly appreciated!

Firstly, how do you tell the difference between the N-channel and the P-channel Mosfets? They both appear to be in the same bag, and I can't tell the two apart 

Secondly, is there any way you can measure an inductance without an inductance meter? Can you apply a signal with a signal generator and then measure the resistance with an ohm-metre, then do some formula work?

Thanks to all who can help!
peter

[ohenry]

Hey all!

I've nearly finished a 41hz amp4 kit, but I've come across a pair of issues I could do with some advice on, and I can't seem to get the 41hz site to work for me.

If anyone can lend any advice, it would be greatly appreciated!

Firstly, how do you tell the difference between the N-channel and the P-channel Mosfets? They both appear to be in the same bag, and I can't tell the two apart  ....

peter

Q4,5 and 6 use the part labeled "SA 1".

Good luck!

[Reverie]

Hey Henry!

Long time no speak.

Thanks for that! Should solve the first problem! 

I'll send you an email when it's all finished. 

[Speedskater]

Use an AC Voltmeter (it doesn't even need to be accurate) a resistor in series with the inductor across the output of a small power amplifier. Output a 1 or 2 Volt sine wave. Adjust the frequency and resistor value until the voltage across the inductor is the same as the voltage across the resistor.

       xL
L = ______
      2 pi f