KX1 Nearly Deaf

[drew.neve]

Gentlemen,

I had a similar experience with my KX1.  I could hear signals fine when aligning and the screwdriver was touching the trimcap, but very little as soon as I pulled it off.
I didn't have desoldering equipment available and knew that I had tried to do some adjusting to my L1 so that was suspect.
When I was finally able to purchase a desolderer, the first thing I did was rework the L1 connections.  It has been fine ever since.

It was perplexing for a while:  I didn't know if the problem was the receiver, the new antenna, or just that there were no stations on the air here.

20M is populated here, but sparsely.  Most of what I hear is European.  I have heard one VA3 call.  I've heard Finland and Sweden both pretty well.  Nobody seems to hear me at all.  I'm working on locating a higher antenna site hoping to reach out better.  I'm fairly limited to 12' tents (no trees).  Radials and poles are out of the question due to a need for secrecy.

CPT Drew Neve - 9K2/KB9LLO
Battle Captain
S3 ASG-Kuwait
Eager to Assist


Hi folks,

I have resolved the "signals getting loud when I touch the board" mystery
with help, but there is still something amiss.  Upon further testing, the
receiver appears to be profoundly deaf. It does hear some signals on 40, and
even some on 20, but not nearly as well as it should. However, I have some
clues here. Attaching the antenna does affect the signal level, so the
receiver is, to some degree at least, seeing the antenna. Also, the receiver
is detecting signals and is on frequency.  It hears my signal source OK, and
even the few strong external signals are perceptible, but again not nearly
as strong as on other receivers here. Another point of note, the background
hiss really doesn't sound like what I would expect. No static crashes, not
the background noise I would expect. Just a dull hiss like you would hear
when raising the volume on a PA system with no input.
Another point, although seemingly unrelated, is the AF gain control gives me
basically no audio until I get to about 3 o'clock. Then it gets loud very
quickly. (This could be a combination of not very sensitive headphones and
the audio taper characteristics of the pot, if in fact it is an audio
taper.). And then just before it hits maximum clockwise position, I hear a
slight "pop" and it gets noticeably louder.  I do realize that I probably
need more sensitive headphones/ear buds, but this would not explain all of
these symptoms.

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[Vin Cortina]

I appreciate your input, CPT Neve.  My problem may be different though.  I
solved the mystery of the signal getting louder when I touch it via a
combination of using a completely non-ferrous adjustment wand and the
realization that when I used my K1-4 into a dummy load in the shack, I was
coupling a much larger amount of RF to the KX1 via capacitive coupling
through yours truly.  L1 probably (?) is not the issue as I get a 0.0 ohm
reading from the center pin of the antenna jack to the schematic "point B",
which of course passes through L1 and L2.

I am going to begin some dynamic testing via crystal oscillator and an RF
probe as soon as I can find the parts I need for the oscillator.  I was
going to use my XG1, but Don W3FPR (who has been helping me along here),
informs me that it doesn't have enough output, so I am going to build the
one from the K2 manual.

Thanks so much for taking the time to offer your experience, it is always
welcome and appreciated.  You take care of yourself.


Best Regards,

Vin Cortina  KR2F

K1-4 s/n:1977
KX1  s/n:1476 (still under construction)


-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of
[hidden email]
Sent: Friday, July 07, 2006 6:52 AM
To: [hidden email]
Subject: [Elecraft] KX1 Nearly Deaf


Gentlemen,

I had a similar experience with my KX1.  I could hear signals fine when
aligning and the screwdriver was touching the trimcap, but very little as
soon as I pulled it off.
I didn't have desoldering equipment available and knew that I had tried to
do some adjusting to my L1 so that was suspect.
When I was finally able to purchase a desolderer, the first thing I did was
rework the L1 connections.  It has been fine ever since.

It was perplexing for a while:  I didn't know if the problem was the
receiver, the new antenna, or just that there were no stations on the air
here.

20M is populated here, but sparsely.  Most of what I hear is European.  I
have heard one VA3 call.  I've heard Finland and Sweden both pretty well.
Nobody seems to hear me at all.  I'm working on locating a higher antenna
site hoping to reach out better.  I'm fairly limited to 12' tents (no
trees).  Radials and poles are out of the question due to a need for
secrecy.

CPT Drew Neve - 9K2/KB9LLO
Battle Captain
S3 ASG-Kuwait
Eager to Assist


Hi folks,

I have resolved the "signals getting loud when I touch the board" mystery
with help, but there is still something amiss.  Upon further testing, the
receiver appears to be profoundly deaf. It does hear some signals on 40, and
even some on 20, but not nearly as well as it should. However, I have some
clues here. Attaching the antenna does affect the signal level, so the
receiver is, to some degree at least, seeing the antenna. Also, the receiver
is detecting signals and is on frequency.  It hears my signal source OK, and
even the few strong external signals are perceptible, but again not nearly
as strong as on other receivers here. Another point of note, the background
hiss really doesn't sound like what I would expect. No static crashes, not
the background noise I would expect. Just a dull hiss like you would hear
when raising the volume on a PA system with no input.
Another point, although seemingly unrelated, is the AF gain control gives me
basically no audio until I get to about 3 o'clock. Then it gets loud very
quickly. (This could be a combination of not very sensitive headphones and
the audio taper characteristics of the pot, if in fact it is an audio
taper.). And then just before it hits maximum clockwise position, I hear a
slight "pop" and it gets noticeably louder.  I do realize that I probably
need more sensitive headphones/ear buds, but this would not explain all of
these symptoms.

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_______________________________________________
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Post to: [hidden email]
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