you can up the feedback resistors from 100R to 150R, I believe that provides some of the gain your looking for. Give it a try.
In which preamp circuit? I don't see one in the b1 circuit.
he meant on altering F5's gain
several times explained in thread
Yes, I will try that. I had been planning to build a version without the limiting circuit. I will try this out too. Thanks.
... and another F5
Soon to be a J2 I might add.... 😉
Soon to be a J2 I might add.... 😉
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Dear All,
I have a recurrent problem when it comes to buy transformers. I temporary live in Japan that has 100 V main. I'll go back to Europe sooner or later with 230 V.
Any trick to use the same transformer in both places, using a 115-230 primary transformer ?
Additionally, do you know any source of toroidal transformer in Japan ? Here is easy to find normal transformers, but I cannot find toroids.
Thanks,
Davide
I have a recurrent problem when it comes to buy transformers. I temporary live in Japan that has 100 V main. I'll go back to Europe sooner or later with 230 V.
Any trick to use the same transformer in both places, using a 115-230 primary transformer ?
Additionally, do you know any source of toroidal transformer in Japan ? Here is easy to find normal transformers, but I cannot find toroids.
Thanks,
Davide
> Any trick to use the same transformer in both places, using a 115-230 primary transformer ?
Yes.
> Additionally, do you know any source of toroidal transformer in Japan ?
Since you are there, you might as well get proper Japanese R-Core.
http://www.kitamura-kiden.co.jp/english/index.html
ƒeƒNƒjƒJƒ‹ƒTƒ“ƒˆ�[
Patrick
Yes.
> Additionally, do you know any source of toroidal transformer in Japan ?
Since you are there, you might as well get proper Japanese R-Core.
http://www.kitamura-kiden.co.jp/english/index.html
ƒeƒNƒjƒJƒ‹ƒTƒ“ƒˆ�[
Patrick
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> Additionally, do you know any source of toroidal transformer in Japan ?
Since you are there, you might as well get proper Japanese R-Core.
KITAMURA KIDEN CO.,LTD.
ƒeƒNƒjƒJƒ‹ƒTƒ“ƒˆ�[
Patrick
I'd love to !! I tried to contact them few months ago for another project, but with no success, and on the open market I could not find their products.
Additionally, Japanese products are almost always 100V only, so no way to use the same transformer.
I'll give another try, anyway.
My idea for the toroid, was to buy the 20 V from Antek. This will give me 18 V in Japan. When I go back to Europe I can reduce the voltage a bit increasing the resistance of the CRC filter. But this is extra heat.
Is there is any smarter way. How is it in the production models for Japan ?
I have also a step up/down autotransformer, but it's a bit noisy and bulky.
Thanks,
Davide
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The boards are my own.
Very nice boards, I like so much your PSU boad
Cheers
Hi,Dear All,
I have a recurrent problem when it comes to buy transformers. I temporary live in Japan that has 100 V main. I'll go back to Europe sooner or later with 230 V.
Any trick to use the same transformer in both places, using a 115-230 primary transformer ?
230:50+50Vac used in reverse for your 100Vac mains to 230Vac input.
or
a tapped autotransformer.
Or dimension for EU, 115-0-115, 2x 18V
paralel the primary
back in EU you use the primary in series
while you are in Japan just live with a loss of output
paralel the primary
back in EU you use the primary in series
while you are in Japan just live with a loss of output
Plitron has some transformers with two primaries 115 V tapped at 100V. If they give me a reasonable price I will go the clean way (easier).
Thanks,
D.
Thanks,
D.
Plitron has some transformers with two primaries 115 V tapped at 100V. If they give me a reasonable price I will go the clean way (easier).
Thanks,
D.
Try Sumr. I think they are a little more accommodating than Plitron.
SumR - Richard Sumner Technology
Why not try a JC-2?
I use one with very good results.
Franz
JC-2 clone is a good candidate, since it is direct couple(no input and output caps), which I like the most.
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Try Sumr. I think they are a little more accommodating than Plitron.
SumR - Richard Sumner Technology
Thanks, really the kind of suggestions I was looking for.
D.
Thanks, really the kind of suggestions I was looking for.
D.
Actually SUMR has universal transformers on one page.
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