[1000mp] Another kind of mod

[1000mp@mailman.qth.net]

Pete, N4ZR wrote:

"According to INRAD, there is a default active low pass filter in both RX
chains of the MP when the DSP is off.  On some radios, the main RX is
flat to about 1.5 Khz, while the sub-RX peaks around 700 Hz and has
considerably lower response above 1000 Hz.  They say adding one .047 uF
cap to the main RX LPF can cut high-frequency hiss by 10-15 dB, and
include the cap as a "bonus" with their IF mod.

I'm wondering if anyone has installed this mod and what you think of it?"
==========
One of the benefits of the INRAD front-end mod is that the IF hiss in the
audio on CW without the DSP turned on is reduced.  This is because you
reduce the IF gain in Menu item 9-1 after installing the mod.

The "bonus" capacitor mod reduced the IF hiss even more than the Menu
item 9-1 reduction in IF gain does.  I was dissatisfied with the amount
of IF hiss that remained after installing the front-end mod, but was
quite happy after installing the "bonus" mod.

If the actual value of C3015 in your MP is not the same as your schematic
shows, shunting it with a .047 uF cap is well worth the effort.

73, de Earl, K6SE