[Elecraft] K2 VCO Test pg 57: Problem -reading 0000 kHz

[k6se@juno.com]

Chris, W5CKH wrote:

"Yes correct signals at TP2 and TP3. 
Yes, I am using a 20MHz scope.
 U4-13 : 5 V DC ; nothing but ripple noise at about 1 mV on my scope. 
 
 U6-6: 5 VDC, 0 V AC on my scope
 U6-7 : 17 mV DC; 0 V AC ; just some ripple noise
 T5 pin 2 = 0 Vrms
 T5 pin 4 = 48 mV DC; 0 VAC on scope
 U3-3 = 4 VDC; AC ripple only

The K2 probe shows the correct signals at TP2 and TP3 - but 0000 kHz at
TP1"
==========
I would think that an RF signal would appear at U4-13, but I may be
mistaken.

Even though you're at the Part II alignment and test, the VFO should work
on all bands.  Even though there's no output at TP1, do you get a
frequency reading on the LCD display?  If not, how do you know which band
you have selected?

If you can see which band is selected, does TP1 still have zilch on every
band?

Also, regarding the LCD display, I assume that Pin 6 of U4 (/PLLCS) is
low when you are not accessing a menu item (or anything else other than
VFO frequency readout).

Also, perhaps something isn't working right in U5, the 12-bit DAC.

Your best bet for help on this is Gary at support@elecraft.com .

73, de Earl, K6SE