MFJ-1025 Noise canceller with a Mark V transceiver

[W2IRT]

Hi all,
I'm suffering S9 to 10dB-over powerline noise here all of a sudden on several bands. I'm using an MFJ-1026 noise canceller on 160 and 80 with great success, using a K9AY loop and a long vertical wire sense antenna, feeding the AUX port. However, the problem is far worse on 10, 12 and 15, and therein lies the problem. The unit is rated for only 100W, and my transceiver is a 200W radio that I like to run full out when not using my amp. Is there any possible configuration that I could use that would allow me to use a noise canceller on my array yet still be able to put out 200W from the radio?

Here in NJ, the PSE&G infrastructure is so bad that they just don't fix anything until it breaks and will deny the problem is theirs even if it is...I went this route in the past. The noise is enough to render HF completely useless unless I'm beamed due north.

[KB4QAA]

It is possible to fry the 1025/26 units, particularly if using the 'RF sense' function for change over.  Best to have a dedicated keyline from the radio.

They also use a lightbulb as an RF fuse.

Given all that I wouldn't try to exceed power limits on an MFJ product! 

 

[WX7G]

Looking at the MFJ-1026 manual it is rated for "approximately 100 watts" (page 9). On page 2 it says "Some exciters overshoot to as much as 350 watts on key closure before settling down to rated power." This tells me that the mechanical T/R relay will handle 350 watts peak. I would give it a try at 200 watts.