[Elecraft] Calibrate TX Gain error

[Gregg W6IZT]

Thanks Guy. Cc'd support

73
Gregg

-----Original Message-----
From: guyk2av at gmail.com [mailto:guyk2av at gmail.com] On Behalf Of Guy Olinger
K2AV
Sent: Saturday, March 27, 2010 10:29 AM
To: Gregg W6IZT
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] Calibrate TX Gain error

Gregg, at one time I had this problem with bandpass tuning on 40
meters.  I would get in touch with K3 support for guidance on touching
up bandpass filter tuning.  I don't believe I've ever seen tuning
instructions that published for a K3.  They told me what to turn and
in what order to flatten it out, though some might want to send the
radio in to have that aligned.  There was nothing missing, burned,
shorted or open on my unit. It has remained tuned since then.   73,
Guy.

On Sat, Mar 27, 2010 at 9:34 AM, Gregg W6IZT <w6izt at bellsouth.net> wrote:
> Good Morning:
>
>
>
> I just ran the TX gain calibration and it fails on 29 MHz at both the 5
and
> 50 watt power levels indicating an SWR of 2.1:1. I checked the SWR
manually
> and indeed it is indicated at approximately 2:1 at 29 MHz. I manually
> checked all bands and 24.9 MHz is indicating an SWR of 1.6:1. On all of
the
> other bands the SWR is 1:1 with the tuner in bypass. I am using a load
good
> up to 3 GHz. I have swept the load and the cable that I am using and the
RL
> is better than -40 dB throughout the HF and VHF spectrum.
>
>
>
> It seems to me that all this points to the lowpass filter in the K3 for
> 12/10 meters. I can do a physical check for a bad cap or cold solder joint
> and it looks like I can sweep the filter by opening W3 and sweeping into a
> load connected to the antenna connector. Before I do this I wanted to
> confirm if anyone else has seen this problem and if so, what was the root
> cause?
>
>
>
> Thanks in advance for your assistance.
>
>
>
> 73
>
> Gregg
>
> W6IZT
>
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