Hi,
I'm currently working on a transformer design, mainly to substitute the LL5402 as a direct replacement. It is a 2+2:1+1 design used in many DIY applications (PEQ, LA4 etc.).
In the past few years I've been producing hifi tube output transformers for special requests.
I'm planning to produce different alternative core options (iron, steel, nickel) at different prices, with some kind of electromagnetic shielding (MuMetal, 3M tape etc.).
I've already made a few prototypes, with which I was able to do some measurements and calculations.
Iron core frequency response at +4dBu: 25Hz - 70kHz (+/-1dB)
Iron core THD at 50Hz +4dBu: 0.11%
Iron core THD at 1kHz +4dBu: 0.009%
Iron core THD at 5kHz +4dBu: 0.008%
The above figures were measured values in real life applications.
Frequency response chart
Total harmonic distortion
I can post the measurements of the steel and nickel core transformers later.
If someone has some kind of transformer design request, I can also consider it.
If there is an interest for the transformers, I may put it on the White Market. I'm planning to offer the transformers at a consideably lower price than the original. I live in Hungary so I can make the transformers easily available in the EU.
Regards,
schawo
I'm currently working on a transformer design, mainly to substitute the LL5402 as a direct replacement. It is a 2+2:1+1 design used in many DIY applications (PEQ, LA4 etc.).
In the past few years I've been producing hifi tube output transformers for special requests.
I'm planning to produce different alternative core options (iron, steel, nickel) at different prices, with some kind of electromagnetic shielding (MuMetal, 3M tape etc.).
I've already made a few prototypes, with which I was able to do some measurements and calculations.
Iron core frequency response at +4dBu: 25Hz - 70kHz (+/-1dB)
Iron core THD at 50Hz +4dBu: 0.11%
Iron core THD at 1kHz +4dBu: 0.009%
Iron core THD at 5kHz +4dBu: 0.008%
The above figures were measured values in real life applications.
Frequency response chart
Total harmonic distortion
I can post the measurements of the steel and nickel core transformers later.
If someone has some kind of transformer design request, I can also consider it.
If there is an interest for the transformers, I may put it on the White Market. I'm planning to offer the transformers at a consideably lower price than the original. I live in Hungary so I can make the transformers easily available in the EU.
Regards,
schawo
