David and all,
I am a little late chiming in here, but all David's points are correct
except for a caution on one.
The alternate winding ratio for T4 should never be used with the KSB2 or
the KPA100 installed. It is OK for power in CW kept below 5 watts.
If the PA is operated above 5 watts,
Surely the binocular transformer is converting the input impedance of
the filter to the optimum load line for the PA transistors. Typically
that would mean such that the the voltage swing was just short of the
full supply rail for the worst case complex impedance, at the worst case
acceptable
Carlos,
Do you have the internal frequency counter probe plugged into TP2? That
is one possible cause, remove it and retest. CW or SSB mode? All
spurious signals should be greater than 43 dB below the carrier level -
they cannot be expressed meaningfully in dBm, only with respect to the
hi, i see 2 spurious left and right from the 3,5mhz main carrier, output 10w,
on 2,1 mhz and 4,9 mhz -40 and -38 dbm with -30dbm attenuation
i wonder i anyone could tell me the correct level for the attenuation
and maybe why this signals are there, not so simple as i stated of
course,and what is
Thanks to those who replied to my post. I've now reached the point where the
level of the spurious tone is low enough. Here's what I did.
Following Don's suggestion I isolated the KSSB2 speech processor from the
balanced modulator by removing C20 and grounding the free end of R2 via a
100nF
Chris
Is the frequency separation exactly 900 kHz? If a bit more, perhaps the
oscillator in the KSB2 MCU (U1/Z1) at (nominally) 4 MHz is coupling into the IF
(nominally 4.915 MHz) path on the same board, on the output side of the crystal
filter). Problems with grounding, bypass capacitors
Chris,
I suspect that artifact is being introduced by the Speech Processor on
the KSB2 board.
Do you know any locals who have a K2? The quickest way to verify my
suspicion is to swap out the KSB2 board.
BTW - TUNE switches to CW even if in SSB mode.
73,
Don W3FPR
On 8/30/2020 1:07 PM,
I built K2 s/n 253 many years ago, and it's been updated with the A-B kit and
all other Elecraft updates. It currently has the KSB2, noise blanker and
160m/2nd Rx options. The ATU is not currently fitted to make access easier,
though it has been.
I'm planning to use the K2 with transverters on
I don't operate the two higher frequency WARC bands, but decided to try
out the K2/100 with the KAT100 using my low band sloping Vee. At
18085.66, I have a moderately strong steady carrier that tunes in
jumps rather than smoothly like real signals. My guess is the
jumps are maybe 150 - 200
9 matches
Mail list logo
