[ARC5] T-22 Woes

[Mark K3MSB]

I think I found the problem….. and I don’t believe it…..

T-54B is gone.  I don’t mean zorched,  burned, etc,  the wiring just looks
gone…… Elvis has left the building……

Here’s two pics,  one from my working T-22 and one from my non-working T-22:

http://www.k3msb.com/temp/t54b_bad_t22.jpg

http://www.k3msb.com/temp/t54b_good_t22.jpg

To see if T-54B was OK, I ungrounded K-54 – stuck a piece of paper between
the relay contact and the ground bar..  I then measured from the roller
inductor to the top of the loading coil T-54A.     I got an open for the
non-working T-22 and a short (expected) from the working T-22.

 T-54B doesn’t look damaged at all…. It just looks like the wiring took a
holiday……

 Am I nuts?

BTW Dick,  I did your checks and they all passed.

73 Mark K3MSB




On Tue, Jun 11, 2013 at 6:55 PM, David Stinson <arc5 at ix.netcom.com> wrote:

>
> I'm betting your tank is not resonant due to Hi-Z contacts.
> This is a very common problem.
> Check the screws that mount the variable caps,
> tank coil and roller coil, especially those that are supposed
> to provide grounds.
>
> Ground one end of your ohmmeter.
> Probe the top tank coil contact.
> It should read grounded.
> If it does not, check the connection at the bottom of the tank coil.
>
> Next,  open the bottom of the rig.
> Gently probe the stator plates of the two front-most variable caps.
> Probe the plates, not the end contacts.
> All the stator plates should read at DC ground (through
> the tank coil).  If they do not, a Hi-Z contact point has
> developed between the stator plate stack and the metal
> strip pressed onto the end of the stack as a connnection point.
> Solder one of the pressed connection points with a sturdy iron, being
> careful not to destroy the plastic
> beads that mount the stators.
>
> Hope this helps.
>
> 73 Dave AB5S
>
>