Well i have been working on this little filter for a long time and now I am happy with it, it works great on my FT818 and IMHO sounds better than the yaesu stock 500Hz filter i have fitted. Really happy with it. Have a look on the kits page and click on the video link .
Well the Crystal sets and the new TRF-1 Kit have been out of stock for a while, its taken about 10 weeks for the Litz wire coils to arrive, then i had a note through the door telling me that the post office are holding them for ransom. i had a to pay them off before they delivered. anyway i have them now and the crystal sets are now available, once i have kited them the new TRF-1 radio will be avaiable too.