Fix for a Linear taper Pot « JT30 – Amplified Blues Harmonica One of the big problems with working with high impedance mics is that a volume control potentiometer must be large enough to match both the element impedance and the input impedance of the amplifier. Volume control pots for high impedance mics feeding tube amps should be larger than 100K ohms and a 1-meg pot is a common value. The actual tonal difference, to my ears, between a 100k and a 5-meg is small. Other differences in the circuit, the qualities of the mic, the characteristics of the amp, and the acoustics of the room are much more noticeable than the small tone changes introduced by the volume pot. The main problem, though with using a large value for the pot is the difficulty of finding an audio taper pot.
Diystompboxes.com Caveats Permission is granted to link to the schematics on this page however I do not extend permission to place copies of the schematics stored on this site on other sites. In other words, you can link, but don't download and place them on your server and show them as yours. Before you go wild downloading these links and buying parts for the schematics listed below, there are a few things you should know. If you don't feel like reading yourself or helping yourself, you shouldn't pursue building your own boxes. Read all the links you can before asking questions. 4ms Pedals: Kits about 4ms Pedals ... contact ... news ... pedals ... custom ... kits ... gallery ... dealers ... for sale ... barter list
College Instrumentation Specialist - NEETS * These files are Adobe Acrobat files that are 100-400 pages in length and depending on your ISP connection speed may take some time to open. You can also save these files directly to your computer without opening them by right-clicking on the link then select "Save Target As". All text below is copied directly from the forward that is in each NEETS manual: The Navy Electricity and Electronics Training Series (NEETS) was developed for use by personnel in many electrical and electronic related Navy ratings. Written by, and with the advice of, senior technicians in these ratings, this series provides beginners with fundamental electrical and electronic concepts through self-study. The presentation of this series is not oriented to any specific rating structure, but is divided into modules containing related information organized into traditional paths of instruction.
View topic - Interfax - Harmonic Percolator Re: Interfax - Harmonic Percolator by Kregg » 17 Aug 2009, 23:34 A problem that I had with my Collins HP was the battery holder was too close to the output jack (which for some reason a stereo jack). The battery made contact with the jack and shorted out the circuit. I could have taped over the battery, but, I thought it best to move the battery holder back a half inch. Guitar Circuits and Schematics: Fuzzi, Amps and other Effects Note: I designed the unique-sounding KOVIAK tube effect for a friend, but here's lots more schematics! The date of this collection is 1995. Fuzz Central I personally do not think that wiring up PNP transistors (Silicon or Germanium) as negative ground is one of the best ideas. The PNP transistors are simply not meant to function with a negative ground and osciallation and "motorboating" sounds are common results of wiring a Fuzz Face with PNP transistors as such. Here's some more information from R.G. Keen: While in theory, the negative ground conversion for FF and other PNP circuits ought to work every time, there are a significant number of times where it causes oscillation, motorboating, etc. Sometimes you can clean this up by putting a big freaking capacitor across the power leads, sometimes you also need a low-impedance 0.1µF ceramic, too, and sometimes you need divine intervention.
Ampeg Scrambler Ampeg Scrambler The Wild Octaver This is the clone of the very rare Ampeg Scrambler, which was built in very small numbers back in the late 60s. Originals are very rare these days and sell of outrageously high prices when one does become available, similar to the Tycobrahe Octavia. Guess what? I love this thing! This pedal is everything that I expected it to be and more! Arbiter Fuzz Face I personally do not think that wiring up PNP transistors (Silicon or Germanium) as negative ground is one of the best ideas. The PNP transistors are simply not meant to function with a negative ground and osciallation and "motorboating" sounds are common results of wiring a Fuzz Face with PNP transistors as such. Here's some more information from R.G. Keen (GEOFEX): While in theory, the negative ground conversion for FF and other PNP circuits ought to work every time, there are a significant number of times where it causes oscillation, motorboating, etc.
Homemade PCBs for Effects Pedal Projects Jun 22 This article looks at a common alternative method to using press ‘n’ peel transfers, hand drawn layouts, or routed boards. This will cover each stage of the process in detail, showing you how to get a good result. You need access to a laser printer, and some copper clad board. Because the normal methods of making a PCB can be relativly expensive, or quite crude (when hand drawn) this provides a cheap, accurate alternative.