Quote: Originally Posted by Nemo de Monet You're not serious, are you? Unless you manage to find a fab house that specializes in radio-frequency (RF) PCBs, what you get is perfectly serviceable everyday ordinary copper on perfectly serviceable ordinary everyday fiberglass. If you do...

Quote: Originally Posted by AudioCats anything that can be sold retail for $3 a piece probably is a "child's play". It isn't a big deal to spend the several tens of thousands of testing equipment to characterize a process until you get it right. Especially when you already make...

What kind of probe are you using? A 1x probe will add more load capacitance to the scope's 20pf which some of the opamps might not like much even though the frequency is pretty low. A 10x probe will minimize the capacitive loading (but make sure it is properly compensated!).

Quote: Originally Posted by FloydCouncil I can find out a transfer function of a circuit with an op-amp, if I assume the Op-Amp to be ideal and all. But if I don't, I don't understand where to get the real transfer function for the op-amp. You can do pretty well by remembering...

Not a really good idea unless you just really want to do it on your own. They can be had for about $3 on monoprice and shipping isn't much so just buy a tested category 2 one. HDMI is a moderate/high speed digital interface. You can't just use a coat hanger and get a usable signal like you...

I am the original owner of (and still own) #422. Been away for a while but I am out of college now and have money again =).

Also, I am trying to avoid simply changing the gain. For the most part the gain is great, but when using it with ipod line out and low impedance phones it is a bit much. I would like to make this cable for use with high gain/low Z phones. It doesn't seem as if it should impact performance...

Hi All, Finished my first amp (PIMETA) a few weeks ago and have been enjoying it a lot. I switched over to the line out of an ipod for my current source and the original gain (I think I came up with something like 10.5 - the multiloop complicates it a bit) is a bit too much for when I use my...

I realize that would work, I'm trying this more as a versatility thing so that I don't have to change gain with different sources/headphones. I didn't have any sockets when I built the pimeta and was too impatient to wait. I don't really see why adding output resistance would change the sound...

Hi All, Finished my first amp (PIMETA) a few weeks ago and have been enjoying it a lot. I switched over to the line out of an ipod for my current source and the original gain (I think I came up with something like 10.5 - the multiloop complicates it a bit) is a bit too much for when I use my...

You might want to switch out the lead-free for leaded solder. It is easier to work with and you don't need as much heat.

Is there any benefit to using the standard (thicker) varieties of star-quad or neglex? I am trying to decide between neglex quad mic cable, neglex mini quad mic cable, and canare mini star-quad audio cable.

Found the answer in an app note I think. Talks a lot about the small signal output conductance and how to calculate it. Then taking output resistance as the inverse of output conductance got a value of almost 2.5 megohms for a JFET cascode of 2x 2N5484. The app note gave output conductance...

Looking at the Class A biasing method for PIMETA, I have a question. I understand the point of the current source (to force the opamp's output stage single ended using the faster BJT's) but am a little confused on the effect that the cascode has on the load resistance of the opamp. The...

Thanks for the help all. I'll keep any further questions to the proper support forum. Excited to start on this after I finish my pimeta.