AudioRoundTable.com: Group Build » A little help posting a schematic

Home » Audio » Group Build » A little help posting a schematic

Show: Today's Messages :: Navigator :: Polls
E-mail to friend

A little help posting a schematic [message #32040]

Thu, 28 September 2006 22:01

Forty2wo
Messages: 163
Registered: May 2009

Master

OK, I drew a nice schematic in CircuitMaker, which saves to a ‘.ckt ’ file, what ever that is. I tried to open it with all of my limited library of imaging software. No dice. So I cut and pasted it into a Word doc and from my end it looks fine. Now how do I move it to the forum? I tried to paste it in but it didn’t take. Wayne I could e-mail you the word doc , but it is probably time to learn to do this…John

Report message to a moderator

Re: A little help posting a schematic [message #32042 is a reply to message #32040]

Thu, 28 September 2006 22:18

Wayne Parham
Messages: 18831
Registered: January 2001

Illuminati (33rd Degree)

You can send me the file and I'll upload it for you. But here what you can do if you want to do it yourself. Do the same copy-and-paste that you did into MS Word, but do it into MS Paint instead. Or if you have another graphics program, you can paste into that instead. Then save the file. Most paint programs will let you choose a format; The GIF and JPG formats are most widely used on the web. Of those two, I'd choose GIF for a line-art drawing or JPG for a photo. You can also select one of the other image formats like BMP, TIF or TGA. Most browsers will display images saved in those file types too. After you have an image file, upload it just like you've done for your amp photos.

Report message to a moderator

There we go [message #32043 is a reply to message #32042]

Fri, 29 September 2006 08:20

Forty2wo
Messages: 163
Registered: May 2009

Master

Thanks Wayne,
The outputs are Dynaco A-470's from a ST-70.The 6a5-G will run a bit harder then a 2A3 or 6B4. I should get about 10 watts with cathode bias...John

Report message to a moderator

Re: There we go [message #32044 is a reply to message #32043]

Fri, 29 September 2006 09:26

Wayne Parham
Messages: 18831
Registered: January 2001

Illuminati (33rd Degree)

Very cool. Can you still get those transformers from Dynaco Doctor or somewhere? How hard are they to come by? What would you estimate is the cost most people would pay to build this amp?

Report message to a moderator

Re: There we go [message #32045 is a reply to message #32044]

Sat, 30 September 2006 23:47

Norris Wilson
Messages: 361
Registered: May 2009

Grand Master

Dyna clone output transformers can be bought here for reasonable money.

Have fun!

http://www.triodeelectronics.com

http://dynakitparts.com

Report message to a moderator

Some Corrections and clarifications [message #32047 is a reply to message #32043]

Mon, 02 October 2006 22:05

Forty2wo
Messages: 163
Registered: May 2009

Master

I have connected the grid, of the lower second stage tube and removed the "primary" of the EXO-173. This was the closest symbol that CircuitMaker had. In Paint I was able to edit it .

this is a work in progress. After Dimar’s excellent series on the design of the SE amp, I though it would be fun to do a ‘practical’.

As it stands now, the amp sounds OK, not great. there is a bit too much bass. I will try reducing the size of the coupling caps.

There is a bit of ringing on the leading edge of a 1k square wave at the output but this may be normal for a P-P amp with no feedback.

Anyone with any ideas, let’s hear them, I’m not proud…John

Report message to a moderator

Re: Some Corrections and clarifications [message #32052 is a reply to message #32047]

Tue, 03 October 2006 16:42

Brucie
Messages: 8
Registered: May 2009

Esquire

Could you expound a little on the input /driver section. At first glance it appears to be an Aikido but it is not (input top tube grid not connected directly to input lower tube plate, for instance).

Report message to a moderator

Re: Some Corrections and clarifications [message #32056 is a reply to message #32052]

Tue, 03 October 2006 21:53

Forty2wo
Messages: 163
Registered: May 2009

Master

No my error, It is an Aikido. Time fro Rev III...John

Report message to a moderator

Re: Some Corrections and clarifications [message #32057 is a reply to message #32056]

Tue, 03 October 2006 22:28

Brucie
Messages: 8
Registered: May 2009

Esquire

OK then; suggest revision of R11 to about 121K for better noise/distortion cancellation. Also, based on my own Aikido experience, I don't think reducing your coupling cap size in and of itself is going to get you where you want to go.
PS: Really nice looking amp!

Report message to a moderator

Re: Some Corrections and clarifications [message #32058 is a reply to message #32057]

Wed, 04 October 2006 22:02

Forty2wo
Messages: 163
Registered: May 2009

Master

Yea, your right there. I had one 82k resister I tried as R 12. it scales about the same. As a driver I did not hear a difference. Perhaps when I get the bigger problems worked out, plus I need to make a parts order.

Lowering the coupling cap to .22uf did make a big difference. I ran a low freq. Sweep and there was a slightly rising response from about 30hz or so peaking at 17hz. The .22uf pretty much flattened it out and it sounds much better. More killing a resonance, rather than true low pass. Plus a bit of hum has crept in, when befor the amp was very quiet. Probably fouled a ground up when I was in there…John

Report message to a moderator

Previous Topic:	The Finished 6A5
Next Topic:	The "Evil" Dr. Brown

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Jan 31 10:54:26 CST 2025