I NEED HELP WITH MY K1

[Len [K4IWL]]

I have a K1 problem. maybe there's someone out there that can point me in
the right direction.
First some background: I am an experienced developer and troubleshooter and
have designed and built many rigs as well as many kits including the K2
#848, the Sierra, and dozens of RockMites and more. But this K1 has me
stumped.

Here are the symptoms: No RF output. RF present on base of Q6 but No RF on
the collector of Q6.
The receive side appears to be working OK. I have traced the RF from the VFO
through the filter and all the way down to the the driver. By the way, I
have replaced Q6 [2SC2166] just in case.

I originally ordered the K1 with the 4-band filter last year but due to
other priorities didn't start building everything until around April of this
year and have been working on it when I have had the time. But now I am
devoting full time to it. My intitial testing was blocked because of
problems with the 4-band filter relay switching so decided to order the
2-band filter (since it is a much simpler device) to help me debug the K1
problem. This has worked so far and the 2-band filter is working normal.
Once I get the K1 problem fixed, I will work on the 4-band filter.

The test equipment I am using is a Tektronix dual-trace scope, digital
voltmeter, two RF probes, XTAL generator (adjustable output). My current
testing is using 7030 KHz input and output.
STARTING ON PAGE 5, APPENDIX E, K1 MANUAL, REV F.

Here are my results from the signal traces.
Although the receive side seems to be working OK, I am also including the
signal trace.

Receiver and VFO (using RF probe and DMM on 3VDC scale):
VFO: U7, pin 1: EXPECTED: .02-.04, ACTUAL: .021
Premix: U7, PIN 7: EXPECTED: .04-.25, ACTUAL: .286
U7, PIN 4/5: EXPECTED: .04-.25, ACTUAL: PIN 4=.027, PIN 5=0
BAND-PASS FILTER: FIL-P1, PIN 6. EXPECTED: .04-.15, ACTUAL: .010
BFO: U2, PIN 7: EXPECTED: .015-1.00. ACTUAL: .010 (PROBABLY LOW DUE TO
DETUNING)
   RF INPUT FROM XTAL GENERATOR SET TO 0.140VDC As per instructions.
LOW-PASS FILTER: FIL-P3, PIN 1: EXPECTED: .12-.16, ACTUAL: .161
T-R SWITCH: FIL-P2, PIN 8. EXPECTED: .07-.12, ACTUAL: 0.111
RF BAND-PASS FILTER: FIL-P2, PIN 1. EXPECTED: .06-.13, ACTUAL: .058
ATTENUATOR AND T1: U1, PIN 1. EXPECTED: .40-.70, ACTUAL: .046
RECEIVE MIXER: U1, PIN 4. EXPECTED: .50-.80, ACTUAL: .476
POST-MIXER AMP: R14 RIGHT END. EXPECTED: .5-.80, ACTUAL: .526
CRYSTAL FILTER: U2, PIN 1. EXPECTED: .30-.50, ACTUAL: .329 (PEAKED)
THE PRODUCT DETECTOR AND PRE-AMPS CHECK OUT OK.

HERE'S WHERE I'M HAVING PROBLEMS:
TRANSMITTER SIGNAL TRACING @ 7.030 KHz
PRE (premix): EXPECTED: .04-.09, ACTUAL: .038
ATTN: EXPECTED: .02-.05, ACTUAL: .016
OSC: EXPECTED: .01-.04, ACTUAL: .010
MIX: EXPECTED: .1-.2, ACTUAL: .114
BUF: EXPECTED: 1.5-2.0, ACTUAL: 1.783
TR1: EXPECTED: 0.5-1.0, ACTUAL: .773
BPF: EXPECTED 0.5-1.0, ACTUAL: .539
TR2: EXPECTED: 0.5-1.0, ACTUAL: .519
TR3 = 0.0  *SHOULD BE OK*
DRV: EXPECTED: 0.9-1.6, ACTUAL: .003 ***NOT GOOD***
PA, ANT, RFD ALL = 0.0 ***NOT GOOD***

ONE FINAL COMMENT: I have spent many hours visually inspecting the involved
components for bad solder joints, wrong values, and missing components. Also
all toroids have been checked for correct windings, continuity, and good
solder connections. (By the way, I design a lot of circuits using toroids
and have wound several hundred in the past 2-3 years so I doubt that could
be where the problem is although no one is perfect.  :-)

I am finally stumped! Any and all suggestions will be appreciated including
test procedures and/or evaluation of my actual test results for weak areas.

I do not have mice in my shack and there are no traces of mouse feces on the
boards. Hi Hi

73 to all,
N.T. "Len" Carlson, K4IWL
Plano, TX
www.qrz.com/k4iwl

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