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75 Ohm switched attenuator, with impedance matching pad.



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The ELV SUP3 Stereo FM test signal generator is just perfect for aligning my tube radios, but as mentioned previously, the output signal level is a little high and needs some attenuation. It has a 75 Ohm output impedance, and the option to switch to 300 Ohm for tube radios is a good idea. This iteration of the project takes into consideration some suggestions received from viewers, and is a stepped attenuator that can be switched up to 50dB of attenuation, as well as an impedance converter, from 75 to 300 Ohms.
The Gerber files will be on the PCBWay share section if you want to order boards for yourself.
Hope it proves helpful.

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TimeStamps
00:00 75 Ohm switched attenuator, with impedance matching pad.
00:10 Intro.
00:45 The new project version.
04:15 The PCBWAY boards.
07:02 The schematic.
10:53 The calculations.
16:30 Built begins.
18:59 Build done.
20:28 Testing.
30:14 Conclusion.

#tuberadios #antiqueradio #radiorestoration

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