Something which I have been planning of testing.
I recently purchased about two sets of Titanium Bullet tweeters about 500 ringgit each set.
The tweeters are meant for cars but I saw in Lenggong BH.
The owner without any knowledge installed it and I was very sure that where ever this tweeter was installed there will be nest above or beside it.
This give the idea to try out and see how good is the tweeter in attracting those swiftlet.
What I did was to combine the installation with fake nests (3 pieces) and at the same time apply the super pheromone.
The four tweeters complete with fake nests were installed at Bujang Valley BH.
Give these test tweeters about 2-3 months and see how good will they work in a BH.
See these photos: