[ICOM] 751A and DB from Heaven

[John Geiger (NE0P)]

Hi Adam and list members

Thanks for the link to the DB from Heaven article.  I have read that before, but never tried it out yet until this AM.  Using my Icom 756 I was listening to and then working JA1NUT on 40 CW.  Noise level here without the CW filters in line was S5.  Adding 6db of ATT lowered the noise level to S2-go much for the 6db per S unit idea.  I think switched antenna ports, lowered the RF gain, and then switched to the main antenna again.  Yes, the noise was reduced, and JA1NUT was a little easier to copy.  Thanks for the tip.  I just worry about the stations I might be missing because they are in the noise, and am wondering which rig would have the best NB and NR controls for taking out that noise at the beginning.

I just looked at the ARRL expanded report for the Icom 756, the MDS for 80 meters, preamp off is -134.9dbm and for 40 meters, preamp off, is -134.2.  That seems overly sensitive on the low bands, as I am sure that all of us get more band noise than that.  So adding the 6db of attenuation probably brings the MDS to a more reasonable level for 80 and 40. The expanded report show the MDS for the FT1000MP to be around -127dbm on 40 and 80 which is probably a more reasonable level.  One nice thing about the 756 series is the incremental attenuator.  Many radios just have 20db, which is probably too much in many cases.  I like being able to add 6 or 12db as needed.  Now if the 756 original just had a manual IF notch....

73s John NE0P 

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