We are somewhat lucky here in the US that CUSTOMS duties do not matter until the value exceeds $800.00.
Most/all other countries will impose duty on all amounts along with the ancillary charges for brokerage, etc..
Noticed some little things that might confuse those even more inept than I.
On the parts list there are different values for the zener string for "left" and "right" channels. I decided to meet them in the middle with 116 volts. (I got my zeners before the list was published)
There is a misplaced K on the circuit board for Z13, I think it is. The band markings are what matter, anyway.
Most/all other countries will impose duty on all amounts along with the ancillary charges for brokerage, etc..
Noticed some little things that might confuse those even more inept than I.
On the parts list there are different values for the zener string for "left" and "right" channels. I decided to meet them in the middle with 116 volts. (I got my zeners before the list was published)
There is a misplaced K on the circuit board for Z13, I think it is. The band markings are what matter, anyway.
Rick, I am not seeing it on the parts list.
Attached all the build docs again. Use these please.
1. Schematic.
2. Footprints.
3. Parts list.
Attached all the build docs again. Use these please.
1. Schematic.
2. Footprints.
3. Parts list.
About Trafo options, we had some discussion earlier. See posts 472-479.
https://www.diyaudio.com/community/threads/schade-common-gate-scg-preamp.380487/page-24#post-7135617
I have used the Antek 120V, 50VA toroid. Originally purchased for the LuminAria, but works very well here. I copied the single secondary to the two channels. Others have provided options from Triad and Hammond. My current working version uses the Hammond EI trafo, but it is quite noisy and produces audible buzzing. The Antek one is dead quiet.
https://www.diyaudio.com/community/threads/schade-common-gate-scg-preamp.380487/page-24#post-7135617
I have used the Antek 120V, 50VA toroid. Originally purchased for the LuminAria, but works very well here. I copied the single secondary to the two channels. Others have provided options from Triad and Hammond. My current working version uses the Hammond EI trafo, but it is quite noisy and produces audible buzzing. The Antek one is dead quiet.
Who knows what I did? Certainly not me.
I have downloaded both schematic and BOM many times and somehow printed out an earlier one when I thought it was the newest.
Mea mea mea culpa ...
Sorry fir the false alarm.
I have downloaded both schematic and BOM many times and somehow printed out an earlier one when I thought it was the newest.
Mea mea mea culpa ...
Sorry fir the false alarm.
Thanks Rahul, is it AS-05T120 - 50VA 120V TRANSFORMER https://www.antekinc.com/as-05t120-50va-120v-transformer/ that you are referring above?
This one has 2 windings of 6.3v which need not be used.
You could use the 6.3V windings to power the filament of some nice looking bottle shape but cheap or defective vacuum tubes, your friends will believe you’ve built a tube preamp, works every time...lol and you get that nice tube glow 👍
The Antek from your link only has 1 x 120Vac secondary winding instead of 2.
The Antek from your link only has 1 x 120Vac secondary winding instead of 2.
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Vunce, Thanks! Wow, not sure how that happens because that label comes from KiCAD. I will add it to the fix list.
Yes, that’s the one. It has a 100V tap that could also be used.
Yep! I have seen that done and the illusion is very strong
Yes and as Rahul suggested he used a single secondary winding of 120v for both the channels on the pcb. But your idea of glowing the vaccum tubes with 6.3v is awesome 🙂
Thanks
For europians toroidy could be a good trafo source
https://sklep.toroidy.pl/en_US/p/ATSS0050-230110V-50VA-step-down-autotransformer/206
https://sklep.toroidy.pl/en_US/p/ATSS0050-230110V-50VA-step-down-autotransformer/206
Attachments
TOROIDY will give you any voltage you want. No need to give the Zener string more voltage than it needs.
I am going to use lengths of wire in the TP holes to make the ZM approved solid connection with the test points and allow 3 meters to be used easily.
I figure 18 gauge solid wire is the biggest one could use but I do not have any so am asking before I buy some.
Is that as large as it will accept?
I figure 18 gauge solid wire is the biggest one could use but I do not have any so am asking before I buy some.
Is that as large as it will accept?
I do exactly the same thing. In fact, I have a collection of cut off resistor and cap legs, ready to be pressed into action.
Hole size is 1.2 mm. Hope I'm reading that right. Edit: yes, it is 1.2 mm, just measured.
Hole size is 1.2 mm. Hope I'm reading that right. Edit: yes, it is 1.2 mm, just measured.