>>
>>Is this a modification which is likely to be beneficial in 160 meter use,
>>or is the major improvement on the higher bands?
>>
>
>There are 2 parts to the Inrad mod--an IF board and a capacitor for
>modifying the audio response. I find both very useful on 160. The IF
>board adds gain which improves reception with a Beverage antenna because
>the 1000MP has marginal amplification gain for lossy antennas like
>Beverages. The capacitor (which they call a "bonus" mod) rolls off the
>excessive high frequency hiss which is present in some 1000MP's (including
>mine) and makes it much more pleasant to use.
First off, let's explain what this mod does: It adds amplification at the
70Mhz IF stage. This to compensate for a lack of front-end gain when
listening to very quiet high bands (such as 15 meters at night, etc.). My
experience with the MP's is that the only bands that really benefit from this
mod are 21 and 24 mhz. Maybe slightly on 14 and 17 mhz on a very quiet night.
Otherwise, the MP has plenty of gain for any situation as long as you have the
radio set up properly (ie., run TUNED mode when needed, use the IPO, ATT, and
RF gain's, and have the menu RF gain set properly).
This mod will do absolutely nothing for you on 160 meters. The radio has
plenty of gain on the low bands as is, and normally requires a fair amount of
attenuation, IPO, TUNED mode, etc. use to maximize dynamic range. If you have
a quiet beverage, you'd be wise to use a filtered preamp on that antenna alone
rather than boost everything up and then clobber your RX when you switch to
the TX antenna.
That said, I've installed the INRAD 70mhz preamp mod on both of my MPs and I
think it's valuable for 15 meter weak signal work, although I think an
external RF preamp would work just as well. The INRAD kit is very high
quality and has very good instructions. I give them an A for their
implementation.
The mentioned Capacitor mod is not an INRAD mod per se, but was initiated by a
9 lander who had discovered that some early MP's had the wrong capacitors
installed on the audio board. Both of mine, one of which is fairly old
already had the proper caps installed. While INRAD supplies this mod
capacitor along with an brief instruction sheet when you by a preamp kit, it's
not really an INRAD mod and certainly not required on most MP's. However, a
lot of this is personal taste as well.
73, Ty K3MM
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