Simple, no-math transformer snubber using Quasimodo test-jig

[Mark Johnson]

In the Linear Audio article tests, {the very worst diode plus CRC snubber}, performed better than {the very best diode with no snubber}.

Circuit engineers can incorporate this finding and apply it, however they see fit.

 

[phase]

I started upgrading power supplies in dacs and preamps using soft recovery diodes with snubber circuits, but now don't bother with the better diodes, just use a snubber with decent quality capacitors...

 

[Mark Johnson]

For DIY projects I prefer a belt, and suspenders, and elastic waistband.

Excellent diodes and CRC snubber on each secondary. I am happy to pay the small additional cost. The Fairchild 30 amp 200 volt diodes used in the RingNot supply, are a personal favorite.

 

[rickmcinnis]

I figured there was something about them considering you using them and then ,in your sly way, saying they are, at least, worth a try.

The measurements are interesting but real experience with a component is immeasurable. When one can take advantage of the knowledge of someone who uses both test equipment and their ears ...

Thanks,

 

[Mark Johnson]

As the admiral used to say, "I'm so rich, I've got money I haven't even spent yet."

 

[Piersma]

Quasimodo boards

hi all,

I have received a batch of Quasimodo boards, through hole version V4.
The surplus is available for DIY members, please drop me a PM if you are interested. Mark thanks for making the gerbers and the design available.

 

[Simon1972]

Piersma, your pm box is full.



I'd love to take one of your Quasimodo boards. How much would it be with shipping to the UK?

Simon

 

[kissmurphy]

Two Boards Left - V4 Through Hole for AU/NZ members - $AU3.20 + $AU(1/1.85) post

Hi Snubbers,

I still have two V4 through hole boards available.

For AU & NZ members only, $AU3.20 each plus at cost postage - $AU1.00 to Australia or $AU1.85 to New Zealand. You can have both or just the one board for the same postage.

See my earlier post in this thread for actual board size/weight and photos:

http://www.diyaudio.com/forums/powe...-using-quasimodo-test-jig-99.html#post4804076

Please PM me.

Regards,
Rob

 

[poisedforflight]

What's my best option for ordering a v4 PCB or kit in the U.S.?

 

[Mark Johnson]

If you search real hard in the Vendor's Bazaar you can find Cheapomodo kits for as little as ten dollars. You can also read post #1 of the Quasimodo thread, find the names of people who have built V4 QM boards, and send them a private message asking for advice, and/or to buy a spare.

 

[poisedforflight]

If you search real hard in the Vendor's Bazaar you can find Cheapomodo kits for as little as ten dollars. You can also read post #1 of the Quasimodo thread, find the names of people who have built V4 QM boards, and send them a private message asking for advice, and/or to buy a spare.

Thanks Mark. Someone's already come through with a PCB for me and I'm working through your BOM now to find the right parts. I appreciate the work you put into this, thanks for sharing it.

 

[bkdog]

I just have to say a big THANKS to Mark and to dsolodov - I built the kit a couple of weeks ago and last week had a fine evening with all of it working and "ringing out" some transformers. The scope traces were just as Mark shows and it was quite fun to damp the ringing. I've cleaned up the power to my DAC and power amps. Cheers!

 

[jameshillj]

Could you describe in simple terms what actual 'change in the sound' (?) that you achieved?

 

[Simon1972]

Gents does anyone have the BOM for the V4 through hole, I've searched the thread but can't find it

 

[kissmurphy]

Hi sqww5917,

Gents does anyone have the BOM for the V4 through hole, I've searched the thread but can't find it

Yup, in the zip file attached to the first post:

Quasimodo_TH_Gerbers_and_everything_else.zip

Cheers!
Rob

 

[Mark Johnson]

Screen capture image:

 

[bondini]

Anyone snubbed the choke in a choke-filtered supply?

 

[herrstagl]

Hello,

Wanted To Buy: 1 thru-hole V4 Quasimodo kit of all parts and PCB. Please reply by Private Message

many thanks and best regards,
tom

 

[stajo]

Hi guys, just a quick question. C1, labeled 1 nF in the schema on first page. I got a 10 nF for that (the only one left) in my V4 kit, is that just as well?

 

[Simon1972]

The choke is usually between psu caps. Doesn't need it generally, certainly not in the paradise pre reg, though the common mode choke is where I apply the rc snubbers.