[Boatanchors] Odd behavior by NRD-515

[Ron Youvan]

On 07/16/2015 06:14 PM, Howard Ritter wrote:

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> The band of decreased sensitivity corresponds so closely to the MW broadcast band that I wonder whether this is a coincidence. It would make sense if the receiver were to automatically switch to a different antenna input when it’s tuned to the BCB, and that could explain the sound of the relay—except that there’s no separate antenna input for a BCB or ferrite antenna. It may be significant that, outside the affected frequency range, the background hiss drops markedly when the antenna lead is disconnected—in fact, to the same level as the background hiss within the affected range. And, within the affected range, the hiss does NOT drop when the antenna is taken off. This suggests to me that the RF from the antenna is not getting amplified within that range. Still, why or how a problem could affect just part of one tuning band and the adjacent part of another band, spanning exactly 1000.0 kHz, remains a mystery.

   My Yaesu FT-990 purposely adds an approximately 10 DB pad in for the 
broadcast band.  The reason is that most stations on that band are very 
nearby and very high power.  (comped to SW stations)
-- 
   Ron  KA4INM - Youvan's corollary:
                 Every action results in unwanted side effects.