----- Original Message -----
From:
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To:
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Sent: Thursday, April 30, 2009 11:57 PM
Subject: Fwd: K2 alignment problems
------------ Forwarded message ------------
From:
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Date: Apr 29, 2009
Subject: K2 alignment problems
To:
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After 3 years I have finally gotten to complete the construction of kit # 5233. The first 2 phases I got completed with only a couple of glitches that with your help I got corrected. I completed istalling the parts for phase 3 and started the alignment section as per the manual. I set power to 2 watts and started to tune L1 and L2 to peak the transmitter but to no avail. Further checks per the troubleshooting guides found the diode and resistors in the first few steps were ok. I did not have any signal at r50 using the rf probe.
I then went back to checks from phase 1 and was ok until I got to the tone freq and pitch test. I now have NO tone or pitch control and no tone. The display shows the correct values as when I first did them during the construction but no tone is present. I did notice when I hit edit to activate the tone the "white noise"went away. Rotating the vfo I can hear faint clicks in the head sets but no tone. I then discovered the "birdy" tone at 7000 is now very faint and goes away totally when I vary the vfo. I can get it back when I hit edit.
Further checks of the transmit section of the rf board finds none of the values listed for the U chips are correct. Mostly where voltage is indicated on the different pins I have either no voltage or double voltage! So far no overheating or smoke is present.
Male logic indicate that the problem is in section 3. I have double checked parts placements, filter and transformer windings and can not detect any solder bridges. Thus two questions.
1) suggestions as to where to start from her and
2) where can I obtain a picture of the front and back of the rf board without any components installed. That would make bridge location a little easier for those close pads that are easily bridged. Holding the board up to a strong light helps but a picture is worth a thousand words or light sightings.
Thanks in advance.
Dan
af4lb
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