[Elecraft] 2T Gen problem

[Don Wilhelm]

Raymond,

I believe the oscillator should oscillate even with Q1 removed.  Look 
carefully at the feedback loop around U1A particularly C2, C4, R1, R2 
and R6.  Be certain the jumper blocks are in the 'T' position.

The most likely problem is soldering or a misplaced component.  Use a 
magnifier to check for any tiny slivers of solder between adjacent pins.

73 and good luck with it,
Don W3FPR

Raymond METZGER wrote:
>  
>
> Hi, 
>
>  
>
> I am in the final alignment and tests of my K2/SSB/PA100, which seems to be
> going very well, . but I am facing my first real problem with an Elecraft
> kit, the 2 T GEN. 
>
> This is rather frustrating, since there are only a few components, no
> toroid, etc.
>
>  
>
> The 700 Hz generator works and produces a max 150 mVolt peak signal, but the
> 1.900 Hz generator does not work. I noticed that Base of 2N3904-Q1 (1.900
> Hz) shows 0 V, while Base of 2N3904-Q3 (700 Hz) shows 2,1 mV. With a 8.9
> Volts Vcc, Collector Q1 shows 8,1 Volts while Collector Q3 shows 6.7 Volts.
> Drains Q2 and Q4 (2N7000) show both 4.4 V (= Vcc/2). The voltages of pins
> 1,2,3,5,6,7 of U1 (LMC6482) are all 4.4 Volts. Replacing Q1 with an
> available spare didn't help and didn't change the voltages.
>
>
>