[Heathkit] HW-16 Warble

[Mark K3MSB]

Removed the 3 tubes in the TX chain, no effect.

Once again, removed the VFO; no effect.

Using a big eraser on a pencil,  I (again) proceeded to tap the snot out of
everything I could find.   The only thing that made a difference was when I
knocked around the VFO tuning capacitor.    Prior,  I had cleaned and
reassembled the trimmer, so banging around the trimmer isn't a good test.
But, with the plates half meshed, beating on the top of them will care a
warble, but that may be due to proximity to the trimmer.

Mark K3MSB




On Fri, Aug 19, 2016 at 6:25 PM, Mark K3MSB <mark.k3msb at gmail.com> wrote:

> Hi All
>
> Well, I saw no changes in the heater when the problem was occurring.
>
> I did notice a small flat topping of the positive side of the heater
> waveform.  I'm not sure that is significant.   Here's a photo:
>
> http://www.k3msb.com/temp/Heater.jpg
>
> Part of the problem is that I may not have the correct equipment here to
> see a very subtle change in a waveform on the scope.
>
> As mentioned in my first post,  I've replaced the tubes for which I have
> spares.    The next plan (and I'm running out of plans.....) is to start
> removing tubes in the transmit chain when the issue occurs.
>
> 73 Mark K3MSB
>
>