Mods...

[Mike Morrow-3]

John/VK7JB wrote:

>About the ACG response time mod :  changing C31 to a lower value cap (from
>2.2uF to 1uF or lower) is mentioned most often...

I've used my K1 (SN 175) for going on ten years, starting with the stock
C31 value of 2.2 uF.  Later, I changed to 1 uF.  That caused a tremendous
improvement in AGC (and S-meter) action.  The last thing that you want on
a CW rig is slow AGC, and 2.2 uF causes an incredibly slow AGC.  I have
absolutely no reservations about recommending use of a lower value.

If anything, something lower than 1 uF might be better, but de-soldering
C31 is not without some risk of damage to the RF PCB if done too often...
I've left the 1 uF cap in place.

I have never read a convincing reason for Elecraft using 2.2 uF for C31.
If you are bound and determined to start out using the 2.2 uF value,
then tack it in place below the PCB so that it'll be easy to remove later
for a more appropriate value.

>there is a  variation of opinion whether C67 should be lowered also.

I wouldn't bother.  The stock value works fine.

There's also been suggestions of changing the KNB1 noise blanker AGC cap C10
from 2.2 uF to a lower value.  I haven't tried that...I don't find the KNB1
to be all that effective on power line noise, which is what I most often
encounter, so I seldom use the KNB1.

>I've read on JL3AHK's site, about a mod to increase OP power of
>the K1 to a consistent 7W across all bands.  He suggests adding a 0.001uF
>cap in parallel with R30 on the RF board.

I've never had problems getting 7 watts out from my old K1/KFL1-4/KAT1/KNB1
system.  I haven't tried this mod.  It's a very logical suggestion, though.

I tried the KBT1 internal battery for 18 months before removing it permanently.
The stock K1 speaker is far better than the micro speaker that is necessary
on the KBT1.  The K1 looks a lot better with the stock top cover and speaker.
The eight AA-cells must be removed from the K1 for charging.  Most importantly,
I don't like having no compartmentalization between the battery cells and the
RF circuit board below them.  These cells do sometimes leak.  Instead, I use
an external AA-cell holder (ten cell) that provides significantly higher
operating voltage, is NOT inside the K1, and is easier to connect to
a charger.

The best K1 battery system I've ever found, though, is a 4 to 5 AH SLA battery,
when weight is not at a premium.

73,
Mike / KK5F
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