2004年8月11日 · Matching of the NPN/PNP pair didn't seem terribly critical. I found that a 2N5087/MPSA18 pair also sounded quite good. Also, the 1M trimmer isn't needed. I replaced it with a 500k-1M resistor connecting collectors to bases of the NPN/PNP pair. In fact, it seems if the pair are high gain transistors, you may hardly need any resistor there.

6 天之前 · Any of the suggestions above will work, just watch the pinout, since it may be different from the MPSA18. A 2N5210 will also work. Depending on your circuit, a 2N2222 will work. If the circuit actually uses all the gain in the transistor (like a twin-t …

2010年6月5日 · The higher-gain trannies like the much-used MPSA18 tend to impart some distortion to the sound of the wah. If you go with really low gain transistors you will most likely have to change the value of some other components (resistors, mainly) to compensate.

2010年6月5日 · They used the same transistors, as you said. The fact that all of these wahs use the high gain transistors is one of the reasons they don't sound like the vintage wahs. I'm sure they use those MPSA18's because they are cheap and plentiful, being that they are mass-produced pedals, and the sound is not a consideration in their choice. Al

MPSA18 vs. 2N5088/5089 May 21, 2020, 02:30:49 PM I just realized that all the graphs in the On Semi datasheets for the MPSA18 and for the 2N5088/5089 are identical.

2008年12月19日 · As long as the MPSA18 isn't considered a military secret, shipping to India shouldn't be a problem. Last edited: Dec 21, 2008 Inside every little problem, is a big problem trying to get out.

2009年7月7日 · For the MPSA18, try a 2N5089. A lot of circuits I've seen call for using either of those. I don't think MPSA18 is a Darlington. According to the datasheet, the HFE for the MPSA18 is around 500-1500. The MPSA13 datasheet actually states that it …

4 天之前 · A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America

2025年3月11日 · 2n5087 is the complement of 2n5088 which is more or less equivalent to the mpsa18, but there might be an mpsa... too. In general NPNs are better regarding noise and gain, at least that's what I have learnt years ago.

2016年5月17日 · Easiest way IMO is to use 3pdt toggle and just put mpsa18 on one outter row and 2n2907 on other outside row, and id just go to radio shack and get some T0-19 2n2907s that are plastic , they have the same pinout as mpsa18 CBE.