|40 dB attenuator built by DK5LH|
Click to enlarge
PA1B 40 dB attenuator. Click for schematic.
He is very pleased with the excellent accuracy of the attenuator, that makes this attenuator suitable for measuring purposes.
Hartmut uses the attenuator to measure the power of his transmitter (2 watts) with a power meter for -80 dBm to -10 dBm
The attenuator is used to reduce the output power of the set to a value that is less than 0.1 milliwatt. (-10 dBm)
|40 dB attenuator with metal film resistors of 2 watt and 600 mW - DK5LH|
Hartmut has used resistors, that he ordered at the firm Reichelt. Resistors 2 watts.
In his email Hartmut writes:
Ich habe diese widerstände nicht ausgemessen, sondern einfach so genommen.
Offensichtlich sind dieses sehr genau.
I did not measure the resistors, but just used them.
Obviously they are very accurate.
The attenuator is built with good available metal film resistors from the E12-series, with an accuracy of 5%. It shows an excellent accuracy, because in practice the resistors show a accuracy of 1.5 %, or better.
The picture below shows the excellent accuracy of each of the four attenuator sections.
Hartmut is very pleased with the excellent accuracy of his 40 dB attenuator. His attenuator shows an attenuation of 40,5 dB, with the maximum attenuation, with all sections switched to ON. He has calculated the attenuation with the method of measuring DC voltages.
Thank you, dear Hartmut for emailing the beautiful pictures and additional info.
It's my pleasure to show your beautifully built attenuator.