smeggy
Member of the Trade: ThunderpantsTP1
- Joined
- Feb 9, 2004
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so I hear tell that it's a bad idea to mount the tube off the board by a few inches with wire. Is this correct and why?
Originally Posted by MrSlim /img/forum/go_quote.gif goes up to 1 3/8", which is plenty large enough for the tubes used in the CTH. In fact, it's just the right size to use a ring from a tube protector to "finish" it up, like the last pic here: |
Originally Posted by sachu /img/forum/go_quote.gif Congrats on your first build...That was really fast considering the components had to be shipped to australia.. |
Originally Posted by runeight /img/forum/go_quote.gif It's simply that any extra wire between the tube and the board introduces opportunity for E/M to get into the signal circuit. And since the buffers in this amp have very high input impedance they will be sensitive to this, including the burst of radiation that occurs when the e12 relay turns on and off. Keeping the tube close minimizes the chances for problems. But there is no hard a fast rule. There is also a switching regulator on the board which generates some noise too. The closer the tube socket is to the ground plane on the board the less opportunity there is for this noise to get into audio as well. Although, IIRC, the oscillating freq of the regulator is 150kHz. |
Originally Posted by runeight /img/forum/go_quote.gif OK. Is the 2227 a jfet input opamp? I have forgotten. Next text is to meaure all of the pins on the buffer opamp with respect to SG and report back. And you said that OG is 12V (or very close)? |
Originally Posted by smeggy /img/forum/go_quote.gif Thanks for that, I think I'll try it see if it's workable or not, I can always stick it on the board if there are problems. Thanks |
Originally Posted by smeggy /img/forum/go_quote.gif Holy crap Sachu! now you're not just putting these bits in place with Blutac are you... |
Originally Posted by smeggy /img/forum/go_quote.gif Awesome!!! It's so cute! |
Originally Posted by Nebby /img/forum/go_quote.gif eagerly awaiting my package to show up so I can get started. Best finish my buffalo build first so I have a source though! |
Originally Posted by sachu /img/forum/go_quote.gif Heh..not as pretty as I could have made it...but I was moving fast on this one. Btw, DO you want me to install the BOM standard coupling caps? OR do you want me to get some fancy caps for them? Basically C4L and C4R which are 0.22uF polypropelene caps. There are many options...let me know. I might socket the caps in case you want to try different caps later |
Originally Posted by smeggy /img/forum/go_quote.gif I dunno, whatever is good. I have no idea what the bigger caps etc do so can't really say. I'll leave it in your drunken hands Oh, did you ever win that tube auction you were going for or should I just order the $30 one from wherever it was? |