@IAIMH
Just wanted to know which Antek you ordered?
ZM said to me:
“Take this as Bible, 10VA per channel, best 30Vct or 2*15V, and you'll solder it on pcb in CT fashion
Why as Bible - there is no need for more, and you must!!!!!! keep size of Donuts lowest possible, to avoid stray magnetic field reaching Turtle itself
Logic calls for 24Vct, also 10VA; also possible to take 2*12V, and you'll solder it to pcb in CT fashion”
I couldn’t find an Antek that was 30Vct or 24Vct…or even one that had a single secondary with the proper voltage.
I ended up with a pair Antek AN 0115 10VA 15 volt and one 0112 10VA 12 volt.
My interpretation of his instructions were that when I wire them in series to achieve the correct voltage that I’m supposed to solder the two connected secondary wires to the center tap pads?
I also ordered shielding covers for them.
Do you think a snubber is really necessary/beneficial in this application?
Where would you mount the snubber?
If you happen to have ordered the same donuts, could post your Quasimodo results?
CN
Just wanted to know which Antek you ordered?
ZM said to me:
“Take this as Bible, 10VA per channel, best 30Vct or 2*15V, and you'll solder it on pcb in CT fashion
Why as Bible - there is no need for more, and you must!!!!!! keep size of Donuts lowest possible, to avoid stray magnetic field reaching Turtle itself
Logic calls for 24Vct, also 10VA; also possible to take 2*12V, and you'll solder it to pcb in CT fashion”
I couldn’t find an Antek that was 30Vct or 24Vct…or even one that had a single secondary with the proper voltage.
I ended up with a pair Antek AN 0115 10VA 15 volt and one 0112 10VA 12 volt.
My interpretation of his instructions were that when I wire them in series to achieve the correct voltage that I’m supposed to solder the two connected secondary wires to the center tap pads?
I also ordered shielding covers for them.
Do you think a snubber is really necessary/beneficial in this application?
Where would you mount the snubber?
If you happen to have ordered the same donuts, could post your Quasimodo results?
CN
as far as I can see, from across Big Pond, AN0115 is having two secondaries, 15Vac each, so good
same for AN0112 - two secs, 12Vac each
now, you only need to grasp how to arrange CT secondary of 2 independent ones
(you have wire colors, easypeasy)
maybe this will help, ignore typos
same for AN0112 - two secs, 12Vac each
now, you only need to grasp how to arrange CT secondary of 2 independent ones
(you have wire colors, easypeasy)
maybe this will help, ignore typos
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Wow, finally, glad to see you are building this masterpiece 👍I am a happy camper...
Thank you to @Zen Mod and @Gianluca
FedEx brought some parts from Mouser and a lovely box from Italy an hour ago.
Need to do quick Quasimodo for Antek donuts that just came in the regular post and install snubbers. Then.. some assembly.
=😁
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@chromenuts
Just got a little pile of each of below. One nice thing is they come potted. 🙂 If you want to use their little steel cans, you'll need to drill it out just a bit to accommodate the screw. 1/4" bit for the perforated base plate and through the potting worked well for me.
https://www.antekinc.com/an-0112-10va-12v-transformer/ (For logic etc)
https://www.antekinc.com/an-0115/ (for audio ... Need two for balanced)
https://www.antekinc.com/ca-001-steel-cover/ (small covers)
Note - All of them will have the little covers, but I only have one on at the moment for test fits.
ZM has provided wise guidance re: placement and how to use them to achieve a CT configuration on the boards.
Separately if you need the information - I love my Quasimodo, but I always wonder if I did it perfectly properly. When I measured the 15V in dual secondary configuration yesterday I got 40R ish. When I measured them in CT configuration I got 33R ish. I settled on 39R as the snubber value using the 0.01uF and 0.15uF values (per the norm) as Cx and Cs respectively. Always double check my work on a Quasimodo.
Just got a little pile of each of below. One nice thing is they come potted. 🙂 If you want to use their little steel cans, you'll need to drill it out just a bit to accommodate the screw. 1/4" bit for the perforated base plate and through the potting worked well for me.
https://www.antekinc.com/an-0112-10va-12v-transformer/ (For logic etc)
https://www.antekinc.com/an-0115/ (for audio ... Need two for balanced)
https://www.antekinc.com/ca-001-steel-cover/ (small covers)
Note - All of them will have the little covers, but I only have one on at the moment for test fits.
ZM has provided wise guidance re: placement and how to use them to achieve a CT configuration on the boards.
Separately if you need the information - I love my Quasimodo, but I always wonder if I did it perfectly properly. When I measured the 15V in dual secondary configuration yesterday I got 40R ish. When I measured them in CT configuration I got 33R ish. I settled on 39R as the snubber value using the 0.01uF and 0.15uF values (per the norm) as Cx and Cs respectively. Always double check my work on a Quasimodo.
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@zm
Thanks for confirming the CT wiring of the dual secondaries. That is how I was understanding it.
@IAIMH
I figured we’d end up with the same Antek parts. I noticed the smaller hardware provided on the potted donuts and intended to bore them out to 1/4” same as you did.
Thanks for sharing the snubber info. Where will you be mounting the snubber components?
Thanks for confirming the CT wiring of the dual secondaries. That is how I was understanding it.
@IAIMH
I figured we’d end up with the same Antek parts. I noticed the smaller hardware provided on the potted donuts and intended to bore them out to 1/4” same as you did.
Thanks for sharing the snubber info. Where will you be mounting the snubber components?
^ I know we have different board revisions, so check yours.
Snubbers are on the main PCB for mine.
Snubbers are on the main PCB for mine.
OK…I’ll cross that bridge when I get to it.
Purdeeee…
I might rub some charcoal paint into the logo…or not. Just wanted something subtle to match my other builds…and the SIT-1 when I get them back together 😉
P.S. I can machine a knob for the rotary controller to fit the recess once I have my lathe set up again…unless you have a link to the one it was made for?
Purdeeee…
I might rub some charcoal paint into the logo…or not. Just wanted something subtle to match my other builds…and the SIT-1 when I get them back together 😉
P.S. I can machine a knob for the rotary controller to fit the recess once I have my lathe set up again…unless you have a link to the one it was made for?
While we are at it, I must confess that in my build I seem to remember using a 30 VA transformer. Bigger is better, right? Then I also used the steel cans. I placed the transformer away from the circuitry so things should be peachy. Whether I use the 6 or the 12 dB gain, at Louder/full volume, the Right channel gets a considerable amount of hum. I normally don't turn it up except when using my phono preamp. In fact, I padded down all inputs by 14DB to compensate for too much gain.
When fighting one problem you encourage others to rise. Start looking for ground issues? The chassis is not grounded since I use a 2 prong plug for AC input. Any ideas out there?
When fighting one problem you encourage others to rise. Start looking for ground issues? The chassis is not grounded since I use a 2 prong plug for AC input. Any ideas out there?
Not exactly related to the knob itself, but you'll also either need to create a little notch in the front plate of the chassis for the nub on the rotary controller or grind off the little nub.
Edited to add pic of a knob from Parts Express (I think) also and to mention that a fairly sturdy pair of wire cutters will also take that little nub right off in one clip. 🙂
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Ha!…didn’t even really start and I already screwed up.
I thought the Pumpkin kit I ordered came with everything to stuff the boards. Got spoiled with your amp kits ZM!
Looks like I have transistors, a few caps, some diodes and headers…EDIT* and some multi turn trim resistors (4ea)…(pic).
So I have to start digging through my still unorganized parts and bins and figure out what I might have on hand…and inevitably what I have to order.
I’m referencing the circuit diagrams I printed from post #136…and also an Eagle generated BOM I found that was posted in the Tips and Tricks thread.
You said “avoid Borbely WCF”. I did a search of all three threads and only found a specific parts reference in Tips and Tricks thread post #126:
“R38 is a part of so called WCF option, which I later excluded from pcbs; White Cathode Follower, rearranged to JFet world by E. Borbely”
Since I don’t know a pickled herring from a White Cathode Follower…do I just not populate R38?…and what other components?
Anything else I can cross off besides what was noted previously?
I thought the Pumpkin kit I ordered came with everything to stuff the boards. Got spoiled with your amp kits ZM!
Looks like I have transistors, a few caps, some diodes and headers…EDIT* and some multi turn trim resistors (4ea)…(pic).
So I have to start digging through my still unorganized parts and bins and figure out what I might have on hand…and inevitably what I have to order.
I’m referencing the circuit diagrams I printed from post #136…and also an Eagle generated BOM I found that was posted in the Tips and Tricks thread.
You said “avoid Borbely WCF”. I did a search of all three threads and only found a specific parts reference in Tips and Tricks thread post #126:
“R38 is a part of so called WCF option, which I later excluded from pcbs; White Cathode Follower, rearranged to JFet world by E. Borbely”
Since I don’t know a pickled herring from a White Cathode Follower…do I just not populate R38?…and what other components?
Anything else I can cross off besides what was noted previously?
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stare at goats for a day more, and I'll collect some brain and post bunch-o-files to address all your questions
as I wrote to IAIMH, considering that I'm sending Duelund Silver Foil caps for all signal carrying caps positions, normally that I opted to save some greenies, on few resistors and elcos
Catch 22 is ......... once ( hopefully sooner than later) when you finish Iron Pumpkin and actually hear it, you will cry realizing how much time you wasted, living IronPumpkinless
as I wrote to IAIMH, considering that I'm sending Duelund Silver Foil caps for all signal carrying caps positions, normally that I opted to save some greenies, on few resistors and elcos
Catch 22 is ......... once ( hopefully sooner than later) when you finish Iron Pumpkin and actually hear it, you will cry realizing how much time you wasted, living IronPumpkinless
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Handy Eagle BOM now printed and easier to stare at goats…
Looks like no Borbely means:
- 0R (aka jumper wire) @ R38 position
- 100R (instead of 220k for WCF) @ R32 position
- C13 do not populate …not sure what C5/3 note means
Anyway…will search my stores for everything else that you didn’t populate as bird seed/SMD critters
Looks like no Borbely means:
- 0R (aka jumper wire) @ R38 position
- 100R (instead of 220k for WCF) @ R32 position
- C13 do not populate …not sure what C5/3 note means
Anyway…will search my stores for everything else that you didn’t populate as bird seed/SMD critters