[DEMI] 432-28 construction

[Shawn Tayler]

On Mon, 30 Jul 2001 17:01:57 -0400, Bob Lear wrote:


>One is the PTC 50 device.  Not mentioned in the assembly instructions
>but is shown on the schematic and says "posistor mounted to xtal".  Can
>anyone give me advice as to correct mounting of this device to the
>crystal.  I'm pretty sure it's probably not done with a rubber band!!!
>I think I can figure out where to connect it in the circuit to run it
>from 9V to ground when the LO is energized as shown on the schematic.

Use your soldering iron to remove one of the legs from the Varistor. 
Then carefully solder the now leadless side of the Varistor to the case
of the Xtal.  Use the lead you removed to ground the case of the xtal. 
SOlder the other lead of the Varistor to the +9V.  Insulate the lead
with some shrink tubing to prevent accidenatl shorts


>Item two is the brass angle to be soldered onto the bottom of the
>circuit board.  My assembly instructions say "position as shown".  Well,
>there is nothing on the bottom assembly diagram showing it.  I think it

Solder the short 90 degree portion down to the ground plain of the PCB
near the center so the long end with the curve sticks directly up.  The
strap will flex against the case top as you install it shorting that
part of the case improving the ground characterstics of the chassis.

Shawn
N7LQ