Search found 42 matches
- Mon Aug 31, 2015 7:17 pm
- Forum: Marshall Discussion
- Topic: Marshall 1959/1987 and 2203/2204 mods
- Replies: 34
- Views: 10137
Re: Marshall 1959/1987 and 2203/2204 mods
In. Should be some interesting reading.
- Sat Aug 29, 2015 11:32 pm
- Forum: Garage Talk
- Topic: TAG problems!
- Replies: 88
- Views: 29085
Re: TAG problems!
But now I can't click on those links and read the thread. you get the below image correct? if so you can just copy past the link in the body, annoying but is what it is. the google warning pretty much screams run away, anyone new searching google will do just that. I'm guessing we all pretty much g...
- Thu Aug 27, 2015 9:37 am
- Forum: Garage Talk
- Topic: TAG problems!
- Replies: 88
- Views: 29085
Re: TAG problems!
Me and the site's search engine are just not good friends. It seems searching from google with a TAG tag produced better results. But now I can't click on those links and read the thread.
- Tue Aug 25, 2015 6:29 pm
- Forum: Garage Talk
- Topic: TAG problems!
- Replies: 88
- Views: 29085
Re: TAG problems!
I get a warning anytime I click on a link to TAG from google. I don't even have the option to go anyways.sepulchre wrote:Still getting the warning from Google. I haven't been here in a long while (insane work hours) and wondered what was up. Hope you guys get that warning down.
- Tue Jul 07, 2015 12:47 am
- Forum: Technical Discussion
- Topic: Purpose of these resistors and caps...
- Replies: 2
- Views: 687
Re: Purpose of these resistors and caps...
Ah, thanks Roberto.
Wouldn't all three be a local feedback circuit then? And I assume they would be negative feedback, right?
Wouldn't all three be a local feedback circuit then? And I assume they would be negative feedback, right?
- Mon Jul 06, 2015 9:40 pm
- Forum: Technical Discussion
- Topic: Purpose of these resistors and caps...
- Replies: 2
- Views: 687
Purpose of these resistors and caps...
I tried to search but wasn't sure what they are called, so nothing came up. This was posted in the fender forum, and I've seen them in other circuits as well. http://ampgarage.com/forum/download/file.php?id=41581 V1B, V4A and V4B all have resistors (rather large value) and capacitors bypassing the g...
- Mon May 18, 2015 5:54 pm
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
from "Design and Construction of Tube Guitar Amplifiers" by Robert Megantz, on page 85-86 for anyone that has the book. It is discussing the reverb driver circuit of a typical fender type reverb. The parallel 12at7, transformer coupled (22.8k primary), 2.2k cathode resistor. It has a picture of the...
- Sat May 16, 2015 11:23 pm
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
Yeah, Blencowe's book has so far been the standard to which others are compared. I really wish he'd do a power amp book. I'd buy two. I'm just reading all I can get my hands on now. Megantz is the current one. It's not bad, but not "complete". There's been a few times I've had to stop and say, "wait...
- Sat May 16, 2015 7:41 pm
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
Ah, right. The working load line wouldn't be as steep a slope because the AC impedance would be greater. Thanks! So what is Megantz's reasoning for just shifting the original load line straight up by 3.7mA and keeping operating point right at the supply voltage? I wished he would have went into more...
- Sat May 16, 2015 3:46 pm
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
Thanks Martin. That makes a little more sense and that method for finding the operating point is the one I'm familiar with from the Merlin book. The final result from the Megantz book has the second load line ending at 415V at 3.7mA, with the operating point being there at -8V. I couldn't figure out...
- Sat May 16, 2015 10:49 am
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
Sorry guys, I guess I've not been clear. The 3.7mA and -8V are unknown values. The known quantities are 415V supply, the 2.2k cathode resistor, and the 22.8k primary. He draws a load line at 0 mA 415V and 18.2 mA 0V. He then states the tube isn't operated a max dissipation so has to find the "actual...
- Sat May 16, 2015 1:46 am
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Re: Help me to understand this please
Thanks Phil
How did he come to the conclusion 3.7mA was what was flowing through the tube (and thus the cathode resistor)? This is where I'm confused. He just states it and didn't go into detail how he arrived at that conclusion.
How did he come to the conclusion 3.7mA was what was flowing through the tube (and thus the cathode resistor)? This is where I'm confused. He just states it and didn't go into detail how he arrived at that conclusion.
- Fri May 15, 2015 11:26 pm
- Forum: Technical Discussion
- Topic: Help me to understand this please
- Replies: 16
- Views: 3134
Help me to understand this please
from "Design and Construction of Tube Guitar Amplifiers" by Robert Megantz, on page 85-86 for anyone that has the book. It is discussing the reverb driver circuit of a typical fender type reverb. The parallel 12at7, transformer coupled (22.8k primary), 2.2k cathode resistor. It has a picture of the ...
- Fri Mar 20, 2015 2:45 am
- Forum: Speakers and Cabinets
- Topic: installing grill cloth...
- Replies: 8
- Views: 2131
Re: installing grill cloth...
The 1x2 is the length of the baffle, (or longer). The corners I cut, and fold the side over. Once the top-bottom is tensioned, and stapled, all that is needed is to tighen the sides enough to remove any slack. I'm going to try it again this weekend. I've cut another baffle...I'll just use whichever...
- Wed Mar 18, 2015 7:08 pm
- Forum: Speakers and Cabinets
- Topic: installing grill cloth...
- Replies: 8
- Views: 2131
Re: installing grill cloth...
Thanks Bill. Is that 1x2 a long piece that covers the length of the baffle? I thought about doing something like that, but then wasn't sure how to get the sides tensioned up that way. What techniques do you use for the corners? Two cuts parallel to each edge at the end of the board? I've got black g...