Power amp under development

Re: I also thank You Q

ppcblaster said:
Perhaps someone like TomWaites can post an assembly manual

and parts list or a kit and/or boards.

I really don't know what to do with a PDF file. Perhaps someone could tell me.

Thank you............Gary

Jump on the net and download a free copy of Adobe Acrobat reader (there are others too). If you use the internet, you will need this for many documents.

After you have the "reader" installed you can crack open Q's pdf and view & print the love.


Cheers,

Shawn.
 
Thank You, too, Quasi! ;)

PDF files in general are print-alikes of documents (of any kind).

The files You're trying to use can't be converted into gerber format, but can be printed out by You or a board house in order to make PCBs via UV exposure techniques.

You should ask Your board maker about their possibilities to handle PDF layouts. But as You can see from Shawn's pictures, this method can be done "Yourself" (DIY). ;)

Cheers,
Sebastian.
 
...I have software...

sek said:
PDF files in general are print-alikes of documents (of any kind).
The files You're trying to use can't be converted into gerber format, but can be printed out by You or a board house in order to make PCBs via UV exposure techniques.
You should ask Your board maker about their possibilities to handle PDF layouts. But as You can see from Shawn's pictures, this method can be done "Yourself" (DIY). ;)
Cheers,
Sebastian.
Sebastion nailed it. I, like many others around here etch my own pcb's at home cause I get them when I want and they are very cost effective if you are willing to work with chemicals. Here is my attempt to explain the process that I use. Watch out, it is a pdf :D


ppcblaster said:
I have Eagle 4 and Altium Protel 2004 and Acrobat 7 .

I have a streak of an artist so I also use photoshop to mess around with the images inside the pdf's (not conventional). I edit them like photos. I too am learning the ways of electronic CAD software and I am still experimenting with low(ish) cost methods. Who knows, I may break down and buy a proper editing suite some day.

...back to Quasi...email me if you have questions about my methods as it is kinda off topic here on Q's thread. Or start a new thread and invite the forum to discuss your tech questions. Everything you ever wanted to know is contained within the brains of these many good peoples!

Good times,

Shawn.
 
Children of Quasi?

Twins? Could be?

Jah,

Shawn.
 

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Sorry , there is a mistake in my previous post, I was asking if its possible to use 2sk1530 on Quasi Amp?, Did anyone tried it already ? I have a half dozen of this component here , I compare the IRFP450 and 2sk1530 , they are both N type Mosfet so (did not check datasheet though) so I was thinking maybe I can use 1530 instead of 450, my mistake sorry again guys..:D
 
2sk1530

...is a winner! It will be good...very good. I don't know of anyone in the Quasi history that has used it YET but as I stated previous, I WILL be using 2SK1530 in my current build of Quasi amps. I should have them tested in a week or two. The only hold-up for me is waiting for my 2SK1530's as they are on the way....:)

Cheers,

Shawn.
 
DC Protection Circuit (substitutes) ?

Hi,

I already have a bunch of little 10uF bipolar caps that I just found in my stash. If I change the value of the 33K resistors can I substitute my 10uF caps for the 20uF caps already being used in the circuit and achieve the same result?

Cheers,

Shawn.
 

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Re: DC Protection Circuit (substitutes) ?

Hi,

I already have a bunch of little 10uF NONOPOLAR :smash: caps that I just found in my stash. If I change the value of the 33K resistors can I substitute my 10uF caps for the 20uF caps already being used in the circuit and achieve the same result?

Cheers,

Shawn.

Typo corrected...:xeye:
 
Hi Tomwaits,
those two input caps need to be Bi-polar or non-polar.

Nono polar could be mono polar or non polar, I cannot tell.

Each half of the 2pole filter has a 700mS RC time constant.
If you replicate the RC then you will mimic the filtering before the detector.

Your proposal will increase the resistors which has the advantage of reducing the voltage going into the detector, particularly if the amp output slews to one supply rail. But will also reduce the detector sensitivity.
 
AndrewT said:
...Each half of the 2pole filter has a 700mS RC time constant.
If you replicate the RC then you will mimic the filtering before the detector.

Your proposal will increase the resistors which has the advantage of reducing the voltage going into the detector, particularly if the amp output slews to one supply rail. But will also reduce the detector sensitivity.


As always, thanks Andrew,

t=rc

t=726uS but there are two RC's in parallel, why? Is t doubled by using two RC's one after the other? Does this make t=1.452mS for the over all RC? I guess two stages of RC help eliminate transients of soft clipping or low frequency audio signals from tripping the relay unnecessarily?

Substituting 50K R's for 33k R's and using my 10uF bipolars instead of the 22uF, the circuit would respond around 1mS. Could be better or worse? I will give it a try or find some better 22uF caps. Your thoughts? I have some time before final assembly.

Cheers,

Shawn.