Mucking around last night on 20m, whilst tuning up I smelt this faint tinge of smoke in the air. Looking around the equipment, I couldn't see anything so I continued eventually powering up to 100 watts (SSB).
Later that evening, I decided to go down to 1/2 watt (CW) as I heard this loud station and thought maybe I could get him. After going down to 5 watts on the Icom 7300, I switched on the Attenuator and ...nothing. No power. After a bit of clicking the switches on and off (they can get "sticky" at times) I then realized that it was switched on when I went up in power previously. Whoops....I just FRIED it.
I had a feeling this was going to happen sooner or later with those push button switches. They are just too small and finicky and can get stuck "on" due to being "sticky"
Anyway... time to build a new one. Only better
Here's a couple of good sites out there on the web regarding attenuators.
https://www.pasternack.com/t-calculator-pi-attn.aspx
https://a29.veron.nl/hams/pa1b/
I also had a look around on you tube for a few ideas and found WV2YAU who had build his own. It looked nice and robust with good switches. He uses 1 watt resistors which is good for 1 to 2 watt tx power output, but I'll use 2 watt resistors (better suited for the 5 watt output of my TX). Overall.. a nice unit
Anyway.. made a list of the required parts. Stay tuned
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