Rap 'n Tap
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From: Henk Blom
Date: 8/21/2005
Time: 3:27:30 PM
Remote Name: 82.169.93.177
most Litz wire can be tinned with your soldering iron and a good quality of soldering tin. The enamel vaporises and the copper wire takes the fluid. Greetings Henk. bolom@tiscali.nl
From: Bruce B.
Date: 4/8/99
Time: 11:31:30 PM
Remote Name: 24.131.150.94
>Two problems: First, radio frequency (RF) >getting into audio circuits. Second audio >circuits demodulating the RF. You can try the >following: 1) Make sure the input shielding is >well designed and has not broken its ground. Yes, the input shielding is good. Actually, a better quality cable INCREASES the problem! I believe it is because the better cable has less capacitance to ground. >If you hear any TV buzz or radar beep under the >AM, use a high-quality cable. No TV or FM. Just the three main stations in Chicago (670, 780 and 1000KHz) >Make sure the amplifiers are designed for clean >linear operation and B. no shorted capacitors >have messed up the bias (thereby causing >non-linear operation). Here is where the challenge is...guitar devices like this are akin to sound generators, instead of linear amplifiers. >Distortion amplifiers will likely demodulate >anything that gets into them. Yes, this device is a distortion device that adds a strong octave sound to a single note being played. >Try Amadon ferrite beads (Owen, Larry what >number?) around the input signal leads. They >give you some RF filtering. I have had this suggestion, but I want to get the right kind. I go to a few hamfests every year. >Amateur radio clubs and suppliers can direct you >to reasonably plain language, low-cost >radio-frequency interference (RFI) books. Let >us know what works for you. I realize this is a tough one and I don't expect 'silence'. I am encouraged because the A/C mods (better ground, .01 cap filtering) have helped noticeably. An audible difference is at least 3 db, so I believe I have already cut out 6-9 db of AM. Anything else I can do to filter the A/C? What about bypass caps on the collectors to B+? I have bypassed the 9 volt supply with a .1uF cap to ground and this helped also. Thanks, Bruce