[Elecraft] KIO2 no oscillator

[Bob Hawkins]

Hi,

I completed KIO2 this morning and started the testing. The radio (K2 #606
with most options) is fine. The mod to the control board (Rev A) is OK.
Side tone is OK.

The KIO2 is DOA. Voltage on U2 pin 1 is supply voltage. Voltage on Pin 9 is
4.97 V. Voltage on pin 8 is 0 (actually tests as 0.12 V positive decaying
to 0 on the voltmeter). There is no trace of the 16 MHz oscillator signal
on the K2 and on an external radio tuned to 16.29 MHz. The oscillator is
not running.

Checking the two boards, I found only one broken wire (ground wire on cable
end on KIO board). Repair changed nothing on the KIO2. The manual trouble
shooting says if oscillator DOA continue with voltage tests...what tests?
All that appears is the software testing part.

The interface is drawing no current. Front panel current when interface in
is 0.30 A. When interface is out current is 0.30 A. 

The voltage table on page 23 provides voltages but no clue. D1, D2 and D3
are O V on both pins. D4 is normal. The pins of U2 are nominal. The
voltages on Q1 are 6.87 V (supply is 14.6 V) on the pin nearest the back
edge of the board (S by the diagram on the back page). The other two are
nominal and 0 V. The voltage on both sides of R2 are the same (nominal)
indicating no current flow on that line.

Help is needed.

73

Bob Hawkins ve3agc