http://draftwebpage.4t.com/TEA5711T%20FM%20Receiver.htm http://www.circuits.8m.com/Fm-radio.htm

Go here for the schematic: http://pg.photos.yahoo.com/ph/aliwag.../ph//my_photos

Eduard Orvisky's Audio Page can be found here: http://www.geocities.com/oviktor/aud9.html It looks like he removed the schematic though. I'll try to post it here.

Anyone know of a good place to purchase these FETs?

I belive it uses a 10-turn pot.

www.Digikey.com has more than 10,000 OPA2134s in stock right now.

From what you described there are only 3 things you need to recheck: Miswired (or short) Backwards capacitor or a bad opamp The easiest thing to do is verify the cap polarity, then throw in any compatible, cheap opamp and see if it works. If not, you'v already narrowed the problem down...

Thanks CETOOLE for the information. I purchased a quantity of 10 and received 12 Noble pots like the ones shown above!!!!

Here's a nice application of this circuit. http://www.pha.inecnet.cz/macura/buffer_en.html

You cannot place opamp power rail decoupling caps, MOSFET gate resistors, and other "distance sensitive" components using wire-wrap. There will be additional noise and/or oscillation if you do.

It's great as long as you don't try to build any high-speed circuits with it. Wire-wrap can be kind of noisy.

Thanks, guys.

I was looking for HP amp enclosures. I would like to have a good Hammond enclosure source. My main concern is: I am in the USA and they are in Europe. I ordered something from China once and it took more than a month to arrive!

http://www.elfa.se/en/ I just wanted to know if they are reliable and fast with the orders. I live in San Diego, Calif. (USA)

...or crd (current regulator diode).

If your just replace the LED with the same color you should be, "at least close" to the right voltage and current. Here are some reference points: Red LEDs: approx. 1.7 volts @ up to 20ma Green LEDs: approx. 2.0 volts @ up to 20ma Blue LEDs: approx. 3.6 volts @ up to 20ma Each color has...

First check to see if the two 9V batteries are connected in series (probably so) on the board. Next, see if there is continuity between the junction of the two batteries and circuit ground. If their is, you should only use a power supply with a V+, V- and ground connection - not a two-wire wall...

The -S and +S is for remote sensing. You can leave them blank or ... Connect the +S to the +Out and the -S to the -Out for slightly better regulation. Here is an example: http://www.power-one.com/technical/remote.html

A lot of guys think these sound better than Polypropolene. Silver mica is used all the time in high-end audio for coupling and decoupling. Take a look at this: http://www.thlaudio.com/soshinmnE.htm

The heat from the soldering iron will crack the glass sooner or later. I know from past experience.

If the original tip came with a silver-colored coating on the tip, don't grind or sand it. If you do you will have solderability problems.

Most older caps tend to be larger because of the materials and mfg process used to make them. Modern caps can be mfg'd with the same amount of capacitance in a smaller package (like surface mount caps for example). I read somewhere that smaller caps tend to have a higher ESR than the larger ones...

You keep saying two 9V batteries in series "doesn't work". What do you mean by that? To me it means you have a short in your circuit. Do this: Put back the two 9V series batteries and turn the circuit on. Then measure the voltage across the batteries. If you don't get near 18V, you have some...

All "decent" soldering irons have a hard metalic coating on the tip that should never be removed or scraped off. If you do, the tip will not be receptive to tinning and the solder will just bead-up on the tip.

Carefully... use a small wire brush on the tip while it's hot --> apply more solder --> wipe with a damp sponge. If that doesn't get the tip clean enough for you, toss the tip and get a new one.