[Premium-Rx] Problem with my long-wire with balun 4:1

[joseph.bozzer at skynet.be]

I don’t understand what’s happened with my 80m long-wire since I installed a balun 4:1 on it

In 20 meter i’ve a SWR <1,5
In 40 meter i’ve a SWR 1,5 =< 2 
In 80 meter i’ve a SWR <5

With the ATU of my FTDX5000 I put all them to 0 but I have a big problem:
- On 40 and 80m all is ok .. I’ve very good results in transmission
- But on 20m it’s a disaster … some LED lamps in my house start to flash at the rate of my CW and the monitoring sound on my FTDX5000 becomes very raucous

It's impossible to use my Long-wire in 20m
What's is happen? ... I remind you that without ATU the SWR is <1.5 over 20m