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Old 28th February 2012, 08:28 PM   #21
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Quote:
Originally Posted by Neutrality View Post
Well, after I found the complementary floating JFET input stage topology I'm never going back to BJT's for input stages and output stages. For VAS, drivers and other stuff I would still use them.
Yeah, I haven't been able to get it to work yet in my simulation software, Tina. I don't have models for the JFETs you specify. I used others but it didn't look too good.
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Old 28th February 2012, 08:32 PM   #22
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Originally Posted by dirkwright View Post
Yeah, I haven't been able to get it to work yet in my simulation software, Tina. I don't have models for the JFETs you specify. I used others but it didn't look too good.
I use these :

.model 2SK246 NJF (Beta=1.07m Rs=56.76 Rd=56.76 Betatce=-.5 Lambda=2.8m Vto=-2.638 Vtotc=-2.5m Cgd=10.38p M=.4373 Pb=.3905 Fc=.5 Cgs=6.043p Isr=112.8p Nr=2 Is=11.28p N=1 Xti=3 Alpha=10u Vk=100 Kf=1E-18 Af=1)

and

.model 2SJ103 PJF (Beta=2.197m Rs=76.76 Rd=76.76 Betatce=-.5 Lambda=735.3u Vto=-2.037 Vtotc=-2.5m Cgd=18.95p M=.5045 Pb=.3905 Fc=.5 Cgs=17.02p Isr=38.48f Nr=2 Is=3.848f N=1 Xti=3 Alpha=10u Vk=100 Kf=1E-18 Af=1)
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Old 28th February 2012, 08:34 PM   #23
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Tomorrow at work I'll see how many boards I have left.
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Old 28th February 2012, 09:14 PM   #24
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I will also be ordering the No-Thump boards tomorrow, cant wait to see how well they work.

Waiting for PCB's is always hard and then finding the time to mount and test them. If only there were more than 24 hours in a day.

Last edited by Neutrality; 28th February 2012 at 09:18 PM.
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Old 28th February 2012, 09:57 PM   #25
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Default THOR

Quote:
Originally Posted by Neutrality View Post
Tomorrow at work I'll see how many boards I have left.
Hi ,
Count me in for one set ,please.ho
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Old 29th February 2012, 04:23 AM   #26
qusp is offline qusp  Australia
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yeah let me know about boards too please
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Old 29th February 2012, 05:32 PM   #27
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I have 5 pairs left in total, so there is still 2 pairs left.

Ordered the No-Thump boards.

Attached is the PCB Layout.
Attached Images
File Type: png Thor No-Thump Board.png (121.2 KB, 490 views)
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Old 29th February 2012, 07:14 PM   #28
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Below info is for those who are interested in a pair of PCB's :

First of all, there will be no BOM with a complete list of components from Mouser, Digikey, Farnell or similar. What I supply is the schematic as attached and a component list generated from Eagle which I have attached as well. So you do have to go out and spend some time and effort sourcing all the components yourself. However, if there is any question about component choice I will ofcourse be answering those.

There will be no handhelding, so a minimum of experience with electronics is required, including soldering(there is a small SMD OPAMP and a few 0603 resistors and caps). Also, you will need a DMM to do the matching of the input JFET's and setting the correct output stage bias.

Payment will be by Paypal.

Price will be $20 USD for a pair of boards + $10 USD packaging, handling,shipping.

If you are still interested send me a PM with :

Diyaudio.com Screen name
Real Name
Shipping adress

3 pairs of boards should be spoken for already so 2 pairs left.
Attached Images
File Type: png Thor_Schematic.png (51.7 KB, 493 views)
Attached Files
File Type: txt Partslist.txt (4.7 KB, 45 views)
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Old 1st March 2012, 02:23 AM   #29
qusp is offline qusp  Australia
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so is there any pics of the boards? smd is good, in fact i would have loved it if all of the small signal and 100nf decoupling was smd. i'll probably get a set i reckon, as i have most parts, but i would love to see pics.

edit: found the pics, for some reason didnt see them yesterday. hmm yeah stuff it I think i'll grab a set. i'm going to have to add an instrumentation amp in front if them though, for bal-se. I could get 2 sets and patch them together but that seems silly.i have to sort out my finances as i have other purchases i have to make today, but i'll get back to you in a few hours

Last edited by qusp; 1st March 2012 at 02:33 AM.
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Old 1st March 2012, 08:06 PM   #30
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20 kHz, 5.6V p-p into a 32 Ohm load simulated FFT.
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File Type: png Thor-20kHz-FFT.png (40.0 KB, 429 views)

Last edited by Neutrality; 1st March 2012 at 08:12 PM.
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