20dB/16W Attenuator

I'm in the process to get building again and have come across this place VK3AQZKITS.

So I bought the 20dB/16W Attenuator, which will come in handy for future projects. Don't be afraid of the surface mount parts in this project, these are BIG legless lizards, and as such don't really qualify as SM. Anyway, the whole kit is very nicely packed and easy to build thanks to the excellent documentation (CD with PDF and VIDEO). Oh, and as a very nice benefit the price is right .... (less then I would be able to buy it for).

I'm not going to pilfer Lou's excellent documentation. But, here are a couple of pictures to show my build.

A couple of small changes, I did not use the two small boards to hold the series resistors, I rather soldered the resistors on top of each other and then across the gap. As can be seen in Pic 2.

I also used my Dremel to remove the paint from the edge of the case to make better ground contact between the connectors and the case, as might be seen in Pic 1. Below is a quick performance check (VSWR & Return Loss).

The yellow line is the return loss of the directional coupler in use, and the pink line the return loss of the DUT, in this case the attenuator. Pretty good up to 2 m (146 MHz) and quite usable on 70 cm (436 MHz). Oh and it is 20 dB attenuation, well close enough anyway.

If you don't have a Spectrum Analyser use a Voltage Source and a DMM.