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xrk971 Pocket Class A Headamp GB
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Old 9th February 2018, 07:08 AM   #1531
xrk971 is offline xrk971  United States
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Yes, a $10 hotplate cooker and a small nonstick aluminum skillet (don’t use for food again). Heat on medium and wait for paste to turn shiny liquid silver. Watch parts align via surface tension and make sure all have melted. Carefully remove plate and place on wet paper towel to quench and quickly remove heat to prevent excessive time components spend at high temps. An IR thermometer is useful if you have one but not necessary if you don’t let it cook too long.

https://www.walmart.com/ip/Elite-Cui...-Plate/8467243
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Old 9th February 2018, 03:41 PM   #1532
DontHertzMe is offline DontHertzMe  South Africa
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Bigger bypass caps, provision for chunky input film caps, and RK09 pot have been added . Input cap footprints are 27.5mm and 22.5mm lead spacing suitable for Wima, Kemet, or Panasonic, as well as many boutique caps.

Board is now 150mm square. I can get it down to around 100 by 130mm at the cost of less elegant traces.

I'm still working on the 20mH inductor. Those things are each 140 by 40mm . Is a ferrite core inductor a no go?

DCA v2.png

DCA v3.png

Last edited by DontHertzMe; 9th February 2018 at 03:46 PM.
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Old 9th February 2018, 04:00 PM   #1533
pcgab is offline pcgab  United States
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Those layouts are looking great!

FWIW, I'm good with the 150x150 layout, it's a desktop build so for me that means having plenty of room to build an all out HA.
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Old 9th February 2018, 08:14 PM   #1534
xrk971 is offline xrk971  United States
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I’m looking into those ferrite toroidal 20mH inductors. They certainly are a lot smaller. We may be ok with 100mA dc current. Those big speaker steel laminated core Erse ones seem a bit out of place and expensive. I can get nice 100mH 10A microwave oven chokes for almost free but of course they weigh 10lbs! But they sound great on my MoFo.

Thanks for indulging our requests - the new layouts look great. I don’t mind a 150mm x 150mm square but I guess we should look into a convenient size and reasonably priced case to with it.
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Old 9th February 2018, 08:23 PM   #1535
Aatto is offline Aatto  United States
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x, do you think 1.5uf as input cap would be ok ?
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Old 10th February 2018, 12:58 AM   #1536
xrk971 is offline xrk971  United States
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If R2 is 47k then 1.5uF gives 2.2Hz F3. So 2 octaves above is 8.8Hz. Should be ok.
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Old 10th February 2018, 02:10 AM   #1537
stellarelephant is offline stellarelephant  United States
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I used 1.36uF on the input of my second mint tin build and the bass is awesome. (The weird value came from stacking two 0.68uF WIMA PPS caps in parallel.)

It will be great to have more room to play with on this desktop board

Last edited by stellarelephant; 10th February 2018 at 02:27 AM.
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Old 10th February 2018, 02:31 AM   #1538
Aatto is offline Aatto  United States
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cool then, i have a pair of Cornell Dubilier 940c 1.5uf laying around, gonna give it a try. caps alone are almost as big as the board itself.
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Old 10th February 2018, 09:38 AM   #1539
DontHertzMe is offline DontHertzMe  South Africa
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Quote:
Originally Posted by Aatto View Post
cool then, i have a pair of Cornell Dubilier 940c 1.5uf laying around, gonna give it a try. caps alone are almost as big as the board itself.
I see the lead diameter on those is 1.2mm. I'll add some bigger pads.
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Old 10th February 2018, 09:41 AM   #1540
JPS64 is offline JPS64  Germany
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Hello BabyDontHertzMe,

would be nice screenshots with trace?!

JP
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