Krill - The Next Generation

[andy_c]

Originally Posted by Steve Dunlap

I have been a little slow getting back to things today. We flooded overnight and have been busy getting someone to pump out the basement. Give me a chance to look over what was said overnight. Can I E-mail you at the address in your profile?

Steve, take as long as you want. Seeing as how it took me over two weeks to respond to this, I've got no room to talk. I hope your basement thing gets taken care of soon, and that the maggies and other items are okay.

It's fine to email me. I just looked at the file size limit for the forum, and it's 976k for zip files. I would think that a schematic would be smaller than this, but if you have a problem posting it, don't hesitate to email.

[Steve Dunlap]

Hi Thomas,

The HiFi is fine. The basement floor isn't completely flat and the stereo is at the high end. It was only about an inch of water in the low spots. I am sitting in my chair, but my feet are wet. The shop is fine. It doesn't have a basement.

Andy,

I guess I haven't tried to post a large file since the upgrade. Wasn't the old limit 100k? I will make a PDF and post it.

[andy_c]

I can't remember what the old limits were. The attachment below shows the new ones. By using zip, you can get the biggest file size even if the file type is one of the others.

[GK]

Originally Posted by Steve Dunlap

I started reading from where I left off yesterday. Can someone tell me where some of my posts went? And why? I had quoted GK in a post that is now gone. I also see that his post was changed after I quoted from it. Are there new rules I should know about? I certainly didn't say anything that should have been objectionable.

The omnipresent Net Nanny
I actually edited that post about 2 or 3 minutes before your reply appeared (while you were typing). It was a remark on the comments of others intent on resurrecting this 'debate'. I deleted it because I figured it would be taken personally.

[scott wurcer]

I have hate mail now so I turn this over to andy_c who I trust totally to be objective.

[Steve Dunlap]

Referring back to my question in post 77,

Krill - The Next Generation

I am not trying to insult GK with my question. Perhaps I am misunderstanding what is being said by either GK or Andy. It seems that Andy is saying the circuit will only operate as I think at high frequencies and GK is saying it can only work at low frequencies. Since these appear to be opposing views, I simply ask which is correct. I could be interpreting on of you incorrectly. Is that the case?

[Steve Dunlap]

As a follow up to my previous question, here is what my simulator says. This was run on the amp that I started this thread with and is the one I will be posting the schematic for later. The first 3 are at rated output of 50W into 8 ohms. This is the minimum current in each emitter resistor at the listed frequencies. You can see how this could lead me to believe the outputs stay on. These numbers lead me to believe GK might be correct at some sufficiently high frequency, but it should be well outside the audio band.

8.87827M amps Minimum at 20 KHz

9.98479M amps Minimum at 1K Hz

10.0355M amps Minimum at 20 Hz

9.99978M amps at DC with 28.3VDC at output with 8 ohm load

[andy_c]

Hmm. The data I was looking at are in your post #4 of this thread. This shows 96uV across a 0.22 Ohm emitter resistor, giving 436 uA per device.

[Steve Dunlap]

Originally Posted by andy_c

Hmm. The data I was looking at are in your post #4 of this thread. This shows 96uV across a 0.22 Ohm emitter resistor, giving 436 uA per device.

Quoting myself from post 4:

You will notice that this amp is of the inverting persuasion. There is no reason for this other than this was what I was working on at the time I decided to do this. I used 0R22 emitter resistors and 34V supplies. I should also state that this amp uses 4 pair of output transistors. Again, it is what I was working on.

I think "working on" is the key here. I changed a few values as I worked on the design. I now feel it is finished. Attached is a Zip file with the schematic in PDF. The node numbers didn't print for some reason. They do show in the print preview. I am also including a screen shot of the schematic which does show the node numbers. I have also included the net list of the complete amp. It will very interesting to see how the results differ between sim packages.

I checked out the Intusoft demo package. The 20 component limit does make it pretty useless.

I just tried to attach the Zip file and was told it exceeds the limit. I will try breaking into 3 files.

[Steve Dunlap]

We will see how it goes this time.