At 10:46 PM 12/25/2001 -0600, Jim Clark wrote...
>I have heard the same for the 890. Also a mod for converting the auto
>tuner to tune TX AND RX.
>Please post here if you have any info!
>Tnx
>Jim, N5QL
>
>-----Original Message-----
>From: yaesu-admin@CONTESTING.COM [mailto:yaesu-admin@CONTESTING.COM] On
>Behalf Of Graham Shortreed
>
>Seasons Greetings to all.
>I'm new to the list, so I hope I'm doing this correctly.
>I've got a FT990 and I read somewhere there is a mod you do to lower the
>noise in the receiver. I understand that it is called a diode mod.
I have an FT-890, and simply replaced all of the 1SS184 rectifiers (diodes are
tubes, aren't they :-) ) before the preamp with Motorola MPN3404 PIN diodes.
There are quite a few in the bandpass filter. I also replaced D2001 and D2002
with MI308 (higher voltage) ones while I was at it, per a Yaesu Tech Bulletin.
www.rfparts.com has both of these types.
I also replaced the 1ss184 (surface mount dual) types up through the roofing
filter, with low capacitance PIN types. Can't remember where I found these
replacements.
It seems to have made a bit of difference by ear. I don't have the equipment to
measure the difference.
Mike - W8UR
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