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

[Eslheadphone]

listening test

That very slight rectifier buzz ( the one I had to stick my ear in the speaker to hear ) is gone. The amp is dead silent. As far as sound quality goes. The Aleph J has always been a great performer. The music comes out of a silent background. A very worthwhile addition to the amp, easy and inexpensive.

 

[thompsontechs]

That very slight rectifier buzz ( the one I had to stick my ear in the speaker to hear ) is gone. The amp is dead silent. As far as sound quality goes. The Aleph J has always been a great performer. The music comes out of a silent background. A very worthwhile addition to the amp, easy and inexpensive.

Cool, so the snubber took care of the buzz. Thanks for the update. I didn;t have my snubber jig until after I build the F5T and was thinking of pulling the tranny, but it's dead silent and a loath to try and get those leads out and back in the PSU. The next build will have monolithic bridge and will be snubbed.

 

[meanie]

Sought and permission was given by Mark to go-ahead....V4TH

So I have sent out to get it to produce, total 10 PCBs. I will be keeping 2, so the rest is up for grab.

USD13 (postage and PCB) to most parts of the world

Anyone interested may PM me.

 

[Eslheadphone]

Mezmerize-dcb1-buffer gets snubbers. The two sections of the secondary in the transformer are different, so the snubber resistors will be different. The Dcb1 is dead silent. Going forward I will include snubbers on all my builds.

 

[jackinnj]

Mezmerize-dcb1-buffer gets snubbers. The two sections of the secondary in the transformer are different, so the snubber resistors will be different. The Dcb1 is dead silent. Going forward I will include snubbers on all my builds.

EI transformers, most those I've tested, have higher leakage inductance than toroidal transformers, while the recipe remains the same, the quantity of ingredients changes.

 

[genechow]

I just bought a very good quality V4 TH kit from Dmitry. Measured my Antek AS-5218 and got a value of 11.2 ohms using the standard C values.

 

[meanie]

Populated the V4TH and fire up for the first time.....Success!





Sorry pictures posted in the wrong sequence.

 

[Mark Johnson]

Looks great, congratulations on your success!

 

[RickRay]

Not cooperating

View attachment infinite.bmp

View attachment 47r.bmp

The first picture is with pot removed, the second is as far as I can reduce damping without it increasing again. I've used this on two other transformers with success, this one doesn't want to cooperate. It is an Antek AN-10440. Any ideas?

 

[Deke609]

... I've used this on two other transformers with success, this one doesn't want to cooperate. It is an Antek AN-10440. Any ideas?

I had a similar issue that turned out to be a problem with the adjustable resistor that came with my kit: a "Bochen 3296W" that started giving me screwy resistances after a short while. Bought a legit Bourns 3296W from a local electronics store and problem solved. So check the make of the 3296W.

cheers, Derek

 

[RickRay]

Primary and other secondaries are all shorted. I did try the other power secondary and it does the exact same thing. 47r gives the lowest damping, anything lower or higher increases the ringing.

 

[RickRay]

awesome suggestion, I'll try lower the resistance with the screw and see if it really lowers.

 

[RickRay]

Derek, I just checked the resistance after turning the screw and it is all over the place. It is a Bochen brand. I'll order a Bourns!

 

[Mark Johnson]

Also buy a 200R multiturn trimmer pot and a 50R multiturn trimmer pot, from a top tier brand like TE Connectivity or Bourns or TT Electronics, sold by a top tier distributor like DigiKey or Mouser or Arrow or RS Components or Element14. The 1000 VA transformer may have a very low leakage inductance, meaning its optimum snubbing resistor value is quite low. When you own low-valued trimpots, you're ready!

 

[Deke609]

Good stuff. I had the same problem and it was driving me nuts until I tested the Bochen - 5 minutes later the Bochen was in the garbage and I was in the car on the way to the electronics parts supply store.

 

[RickRay]

I will order an assortment, thank you Mark!

i had a cheap 1k spare pot and guess what, I now have a damped transformer!

 

[RickRay]

I'll post the pic in a few.

 

[RickRay]

View attachment 15.bmp

Another successful snubber!

 

[RickRay]

Mark, you were right, the resistor value is 15r.

 

[JeffYoung]

I think I spend as much time & effort these days learning how to identify counterfeit and crap parts as I do learning how circuits work. I'll admit sometimes the detective work is interesting, but it still seems like a colossal waste of human endeavour....