[Elecraft] VCO control voltage.

[Don Wilhelm]

Alexander,

The most likely problem is a solder short on the thermistor board in the RP3
position on the RF Board.  A quick indicator is to measure the voltage at RF
Board U6 pin 5 - if it is not veery close to 4 volts, then surely there is a
problem on the thermistor board.

Several other things that may be incorrect - wrong core used for T5 - the
color should be yellow, inadequate stripping and tinning of the T5 toroid
leads, T5 secondary winding in the wrong direction, incorrect capacitors in
the VFO Range Selection part of the VFO, varactors incorrectly placed or
incorrect type varactors.  This is only a partial list of possibilities, but
are the most common causes of failure.

73,
Don W3FPR


> -----Original Message-----
>
> I can't adjust right voltage (6 Volts) on R30 by L30.
> On 4000kHz and 7300kHz DC=7.95V and L30 no turn more.
> On another friquencies DC on R30 is right: 1.5V<DC<7.5V
> All capasitors and diodes was soldered by it nominal.
> T5 transformer are Ok. It have 16red turns and 4green turns.
> I don't know what to do...
>
> PLEASE HELP ME. IN MY COUNTRY HASN'T MORE K2-OWNERS.
>
> --
> 72 & 73! de UR5LAM
> Alexander Ponomarenko
> RU-QRP-CLUB  #103
> mailto: ur5lam at bk.ru
>