[Elecraft] RE: More Audio OUTPUT please: The ongoing saga...

[Bruce Thompson]

I have had a big problem with my audio output.  (I made were several
posts about 6 weeks ago.)  I am trying to use the K2 mobile and the SSB
audio was not high enough to use it in this application.  (CW is OK) Too
much road, wind, air conditioner,background noise.  I've spent quite a
bit of time on this issue.  I now have a way to use it in the truck with
the RF and AF gains on full blast with the preamp on with an external
speaker about 2 feet from my head:

Removed C180 in the 2nd xtal filter section.

Rewound T7 for 20:5 rather than 13:3 turns ratio.  The newer units
should already be at 20:5.

Replaced R1 with a 33k resistor, from its original 51k.  This is because
the voltage on the 8 volt regulator was 8.4 volts, not 8.0.  According
to Elecraft, this was reducing the RF gain.  Changing out the resistor
gave it a little more gain.  Note that it is relatively easy to measure
the regulator voltage with the top cover off so it should be simple to
check.

The rig/ant combination does work.  Antenna is a Stealth II screwdriver
with the 4" coil and a 4 foot whip.  Good signal reports and some DX.

There was one more suggestion to replace one of the resistors in the
preamp stage to get a little more gain but can't seem to find it in my
notes right now.   I have not done that yet.

I also think the antenna has a lot to do with the signal level and thus
the available audio level but I haven't experimented with it too much.
(Have a 2 element Fluid Motion portable beam on order) I also agree with
the comments of Mike AD5IU with the only one exception being my K2 is
one of the earlier units and it does exhibit the audio (should rename it
gain) problem.  

Tom (N0SS) and Gary, I am more than willing to help out finding the
problem.  I have been on a long business trip so I have been away from
the rig/test equipment for a while.  I have been considering buying
another SSB board to see if the newer board/crystals make a difference
or if there is something wrong with my board somehow.  I get to build
something else and I'm sure I could sell a completed board for about the
cost of the kit.  That might be better than trying pull components on my
current board.  I might end up with nothing!  Tom and Gary, let me know
how I can help out.  If you want me to ship you my SSB board, K2, etc.
let me know and we can work something out.

On a side note, after my last "low audio" set of posts, I received a lot
of private email saying something to the effect of, "I also have low
audio.  Please let me know what you find out..."   I personally think
there is something going on here that is more than a single instance.  I
had to go through the "you built it wrong", "you aligned it wrong", "you
connected it wrong","you're using it wrong" ,"you listened to too much
rock music"...    No, it's not built wrong.  No, I have never had a
problem with badl toroid leads.  No, the alignment is just fine (via
Tom's noise source and spectrogram), Yes, I am using an external
speaker.  Yes, I have the preamp on, etc.  No, I didn't listen to too
much rock music.  (I grew up in Iowa and rock music didn't get to my
home town until the late 80's.)  It is encouraging to see Tom and Gary
looking to see if there is a bigger issue here and I want to support
that effort.

Bruce "Not an unhappy customer, I use it all the time, just want to be
able to hear"  KG0SH

K2 SN 549 all options including the KPA100 except the 160m option.  



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