[Premium-Rx] HF-2050 VFO issues...update

[Paul]

Thank you to those who have replied with great suggestions. I haven't had
time to investigate them yet, but just an update on behavior.

 

The radio works 100% when cold, and for the first 20 minutes or so.then the
VFO freezes and doesn't work at all. I can enter freq. with the keypad, and
the radio works 100% otherwise, just the VFO is frozen.

 

That's the update for now. I should have some time this weekend to do some
more work on it.

 

Thank you again,

 

Paul

VE7KHz

 

"the real problem is the tuning VFO. It sometimes does nothing when turned.
The frequency doesn't change. Then after a second or 5, it starts wildly
changing and jumping all over.  Sometimes it works 100%. I completely
disassembled the optical encoder and everything looks good. I am going to
publish an article on this procedure as I also fixed the horrendously stiff
shaft. It's actually pretty simple if you are careful and take your time. 

 

So, I am thinking maybe supply ripple, a bad tantalum cap or ????  I
reseated all the socketed chips but haven't really gone diggin much
further."