Friday night date with Chubby Clementine

[TomMcNally]

I put this Chubby Clementine together last night. Fell asleep listening to Jimi Hendrix ... sounds great.
I used my first Antek Toroid in one of their covers, an AS-1T300. James JS-6113HS outputs, and the
ubiquitous Hammond 156-R choke. PSVane KT-88T's and generic Russian 6SL7 equivalent.





A few more of my amps at http://tmamps.com

[fiftyfivefilms]

Nice build Tom!! love that Ankek....I've been hoping to use one in My "Chubby" build...but the only one available was the AS-4T320,and now I've created a cloud of confusion over its compatibility,...Oye! BTW alway appreciate your posts, they are most helpful.
Kirk

[fiftyfivefilms]

Hi Tom,
I was hoping you could offer some advice. I'm building an "Ultra" with an Antek The AS-4T320 ( over kill I know but a long story!)..I've posted this question on my thread "Advice on a Clementine build" but knowing how busy Shannon is I thought I'd ask here as well.

The Yellow/ White leads..one pair goes to J-5... but from your photo it looks like the other pair is soldered to the ground eyelet.. is that correct?

I had another question regarding the grey wire 70v tap on my transformer..If you would care to weight in on that I've posted a diagram on my thread.

Again thanks for your time, I've built several of Shannon's designs and your site has been my fall back for a visual and is much appreciated.

Cheers,

Kirk

[fiftyfivefilms]

Hi Tom,
Shannon answered my questions so I'm good to go!...just one thing about the Antek.. Do you keep the plastic wrapping on or remove it?

Cheers!

Kirk

[battradio]

Hi Tom,
Shannon answered my questions so I'm good to go!...just one thing about the Antek.. Do you keep the plastic wrapping on or remove it?

Cheers!

Kirk

Hi Kirk ,

Do Not remove the Plastic film !

[fiftyfivefilms]

Hi Tom,
Shannon answered my questions so I'm good to go!...just one thing about the Antek.. Do you keep the plastic wrapping on or remove it?

Cheers!

Kirk

Hi Kirk ,

Do Not remove the Plastic film !

Thanks Mark!...

[TomMcNally]

Sorry for the slow reply ...

The Antek high voltage windings are a little tricky. You need to put them in series, by connecting the "yellow and white" the issue is you don't know which is which. What I did is connect a low voltage AC transformer (9 volt wall wart) to the primary, and then carefully measured the secondary voltage, which when correct is about 70 volts. If you have it right, the windings "add" and if incorrect, they subtract. Easy ! I had to do the same thing with the two 6.3 filament windings, as the color codes on my transformer didn't match the documentation.

Good to hear the pics on my web site are inspirational. I often look back at my own amps for layout ideas too.

This is my first go at a big toroid, so far so good. Next time I'll go with a bigger chassis, the normal 12x8x3 is just big enough for the Clementine and James outputs.

[fiftyfivefilms]

Sorry for the slow reply ...

The Antek high voltage windings are a little tricky. You need to put them in series, by connecting the "yellow and white" the issue is you don't know which is which. What I did is connect a low voltage AC transformer (9 volt wall wart) to the primary, and then carefully measured the secondary voltage, which when correct is about 70 volts. If you have it right, the windings "add" and if incorrect, they subtract. Easy ! I had to do the same thing with the two 6.3 filament windings, as the color codes on my transformer didn't match the documentation.

Good to hear the pics on my web site are inspirational. I often look back at my own amps for layout ideas too.

This is my first go at a big toroid, so far so good. Next time I'll go with a bigger chassis, the normal 12x8x3 is just big enough for the Clementine and James outputs.

Tom,
Thanks for the heads up... I was wondering about how to approach that... I don't have a wall wart so I'm going to use my Variac @ 9 volts....I think I've got an understanding of how to proceed but no doubt some confusion will arise...I've got my entire build done and ready to go.....hopefully tomorrow!!!
Cheers,
Kirk

[fiftyfivefilms]

Sorry for the slow reply ...

The Antek high voltage windings are a little tricky. You need to put them in series, by connecting the "yellow and white" the issue is you don't know which is which. What I did is connect a low voltage AC transformer (9 volt wall wart) to the primary, and then carefully measured the secondary voltage, which when correct is about 70 volts. If you have it right, the windings "add" and if incorrect, they subtract. Easy ! I had to do the same thing with the two 6.3 filament windings, as the color codes on my transformer didn't match the documentation.

Good to hear the pics on my web site are inspirational. I often look back at my own amps for layout ideas too.

This is my first go at a big toroid, so far so good. Next time I'll go with a bigger chassis, the normal 12x8x3 is just big enough for the Clementine and James outputs.

Tom, so I ran this up to 9v on my variac, and found the yellow/white pair with the larger value. My question, does the larger value pair connect to the grounding pad? or does the lower value pair connect to the grounding pad?
Thanks and Merry Christmas!
Kirk

[TomMcNally]

They aren't pairs the way I have them twisted ... it's the "top" white and the "bottom" yellow, while the "center" white and yellow are twisted together and grounded. You are making a "center tap" with the center pair. When you series up the windings for testing with low voltage AC, you're looking for a high reading. If you get a low reading, reverse the pairs. In other words, when they are correctly in series, you will get a higher voltage than you get with them wrong. When you get it right, connect the "center" white & yellow to ground and use the other two for your high voltage. The voltage of the individual yellow and white winding sets doesn't matter.

[fiftyfivefilms]

They aren't pairs the way I have them twisted ... it's the "top" white and the "bottom" yellow, while the "center" white and yellow are twisted together and grounded. You are making a "center tap" with the center pair. When you series up the windings for testing with low voltage AC, you're looking for a high reading. If you get a low reading, reverse the pairs. In other words, when they are correctly in series, you will get a higher voltage than you get with them wrong. When you get it right, connect the "center" white & yellow to ground and use the other two for your high voltage. The voltage of the individual yellow and white winding sets doesn't matter.

Tom,
Thanks again,I think I've got it now,

if I understand you correctly this is how:

Twist the yellow and white together to form the center tap, but test for voltages on the "top" white and "bottom" yellow on the remaining two. Reverse the procedure to to find the best combination (the highest reading)...once you find the right combination ( highest voltage on the "top' and "bottom") solder the center tap to the grounding pad and remaining two for high voltages...Ahh!

Thanks again!
Kirk

[TomMcNally]

Well, almost ... you have to make sure you're not shorting out the winding. You need yellow from one and white from the other. But the right ones. Antek would have made it a lot easier using different colors! Measure yellow to white (ohms with power off) and use two to test with that don't have readings between them. It's that phasing that's important, they will short, add or subtract depending on how you connect them.

[fiftyfivefilms]

Well, almost ... you have to make sure you're not shorting out the winding. You need yellow from one and white from the other. But the right ones. Antek would have made it a lot easier using different colors! Measure yellow to white (ohms with power off) and use two to test with that don't have readings between them. It's that phasing that's important, they will short, add or subtract depending on how you connect them.

Hi Tom, Before getting your last post I gave it a whirl and the magic smoke escaped!
In my impulsive state and using my methodology I forged ahead and brought it up slowly with my Variac..@90V it tripped the fuse, thinking I had it wrong I reversed the wires, again started up slowly and got some smoke on the primaries...OYE!

Then after reading your last post I checked continuity, I now have readings between all 4 yellow/white wires so I think my PT is toast...

Now I wonder should I just get the recommended Dynaco PT or try another Antek!!! ( your Antek only has 50mA is that enough for an Ultra?)...hopefully I haven't damaged any components on the board with my missteps.

but again thanks for your help..I always seem to run into some type of problem with my builds but I haven't been defeated yet! I've built a G*S*G and a Stereo 35 and a Budgie... so I think theres hope..

Cheers,

Kirk

[tmbg]

Where can you get the antek transformers? I've tried to find them in the past and been unsuccessful.

[hilldweller]

Where can you get the antek transformers? I've tried to find them in the past and been unsuccessful.

You can get them here but their web site is currently under reconstruction. Try Monday
http://www.antekinc.com/index.php